The Romance of the Ranchos, San Diego, 1827. Carillo, senior editor of the Lopes with American Captain, Los Angeles, 1831. Carillo writes first book published by a Californian, Los Angeles, 1837. Carillo named Governor of California. The title insurance and trust company of Los Angeles presents the Romance of the Ranchos, a dramatization of the colorful events and characters which form the background of history of our southern California. Each week our wandering vocero Frank Graham has come to the microphone with another true story of the days of the Dones. Now you can do something practical, something fine for the men and the navy. Sailors, marines and coast guardsmen everywhere look to navy relief to aid their families at home in times of emergency and distress. Since Pearl Harbor, demands upon navy relief have been the greatest in history. So now southern Californians are being asked to help raise $500,000. You can match the navy's courage with your response. Be generous in your aid to navy relief. Be sure to listen for a special gift offer which Frank Graham will make later in the program.  Buenas noches señoras y señores. Tonight we end our present series of the Romance of the Ranchos, and as a fitting climax to these programs we're going to tell the story of a family. A family which throughout the history of the Southland has been recognized as one of the great families of California. Listen to the dramatic and romantic incidents in the lives of the Carillos. It's a colorful chapter of the Romance of the Ranchos. The story of the Carillo family in California starts with the earliest history of the province. What was in the year 1769 when the first expedition of white men under Governor Gaspar de Portola came north to San Diego, but the first chapter was written. Among that party of the first settlers was a soldier by the name of Jose Raimundo Carrillo. He was married by the great Padre Junipero Serra and started a family which merged many of the great families of California into one kinship. But not before he was made a captain in the army. Through the years the Carrillos married Delegueras, Picos, Castros, Vallejos, Ortegas, Bandinis and Delvalles, as well as Americans like Henry Fitch and John Wilson. But at first Jose Raimundo's family consisted of four sons and a daughter. The eldest son, Carlos, followed in the footsteps of his father and became a sergeant in the procedural at Santa Barbara. It was there in 1817 that he saw unexpected action. All right, senor. Yeah, you are in a hurry, senor. See, I come from Monterey to warn you. Warn us? See, privateers. The devil Bouchard has landed in Monterey, sucked the city. He sailed south even now. Caramba. And he will surely try to land here. Or up at the cost that I'll reveal you. Oh, see, at the ranchers of the Ortegas. See, I shall want a new horse to ride onto the south. See, see, and ride away. And we go here and we must prepare our defenses. Sergeant Carlos Antonio Carillo headed the small company which went to the Ortega ranch and routed the famous privateer Bouchard who had indeed landed there. It was after the fighting was over that some of his men approached Carillo. Sergeant Carillo. See, what have you there, Sergeant Lugo? You have captured some of them? See, three. And he will not hang them, Carlos. He insists that they be spared, especially the big one, the one that fought like a tiger. Oh, and why not, Sergeant?  Jose, the Englishman. But he is a member of the devil Bouchard's crew. Not anymore, for we have captured him. One Ortega wanted to string him up pronto, but he bought his sergeant Lugo stuck. It's not that alone, Amigo Mio. There was another. Oh, and who was that? The senorita Guadalupe, Senor Otega's daughter. It seems she and the big buffalo Jose have met before. You understand, eh?  Romance, eh? Well, then, senores, who are we to interfere with love? Of course he shall not be hung. I have offered to take him in my home and be responsible for him. So very well, senor. And perhaps the senorita may teach Jose the Englishman to stay here in California and not meddle with privateers, eh? Sergeant Corillo participated there in one of the most romantic episodes of California history. When the American, Joseph Chapman, called Jose the Englishman, was captured. With the help of a beautiful senorita, later became an outstanding citizen. But a few years later, another romantic chapter in the history of the Corillos was being written. It was in San Diego, where Jose Raimundo's cousin Joaquin had a beautiful daughter who captured many an eye. And one day in 1826, an American ship captain came ashore. So this is San Diego. This is it, Captain. Not much to look at, is it? Well, that depends. This town is a little backwards, perhaps, but it might be a fine place to live. Not for me. If I were looking for a place to lie back and dream, I'd take the Sandwich Islands. Now, there's a place a man can relax. And those hula dances and the grass skirts would be... You can have your hula dances, Albert. I'll take the vision of loveliness as he's coming down the street. What are you talking about?  Look, that girl. Have you ever seen anything more lovely? Which one? Oh, you mean that one coming toward us? Yes, she's beautiful, gorgeous. Captain, you're the one that's lost his eyes. And she couldn't compare to those hula... But you're fine, culture too. Albert, there's a dream. Wait a minute. I'll get a closer look. I don't know what to tell you what to think. I wonder who she is. Orange Asker. Well, why not? Good day, miss. Oh, no? Oh, I mean, Buenos Dias, senorita. Buenos Dias. I do not know you, senor. No, I... Oh, I hope you won't be offended that I spoke. It is not the custom in my country to speak to a lady you do not know, senor. Well, I'm Captain Henry Fitch, master of the brig Maria Esther. That's your service, ma'am. Oh, a ship's captain. That's right. And this is the first time you have visited San Diego? Yes, ma'am, the first time. Then it is no wonder I do not know you. Well, I hope that that situation may be remedied. That is, I hope that perhaps we might become friends. Oh? That is not for me to say, senor. You must see my father and obtain his consent. Oh, well, of course. I will only... Who is your father, senorita? He's Don Joaquin Carrillo. You do not know of him? No, I'm sorry. I don't. But I shall. And I'm sure that he must be a fine gentleman to have so lovely a daughter. Oh, senor, you must not say such things. It is not proper. But I'm only a helpless man, senorita. Helpless before your beauty. And when I see such an angel, I cannot help her. Senor, I will not stay and hear such things. Wait, senorita, I didn't mean to offend. But you have said far too much, senor, for the present. If you have more to say, you had better see my father soon, senor. I certainly shall. But, senorita, wait. Come back. What, senorita? Oh, Albert, she was interested. She wants me to call on her father. I couldn't hear much of the conversation, captain, but she did smile. That smile of an angel. To find out who she is, yes, the daughter of Don Joaquin Carrillo. Carrillo? Yeah. Then that was senorita Josefa, the most beautiful girl San Diego. Of course. That's what I told you. But she is... Well, that is the governor. What about the governor? Well, Governor H.C.R.D. wants to marry her. The governor? Yeah, they're almost, well, practically engaged. Almost, but not yet engaged? Well, that's what I hear. Then it's not too late. And the governor had better look to his laurels because he has a rival in Captain Henry Fitch. And Captain Fitch was a formidable rival. Within a short time, he'd won the heart of Josefa, and the governor lost out. Don Enrique, as the captain was called, embraced the Catholic faith, and everything was ready for the wedding. But on the great day... Josefa! My child! Brito! Oh, you know Don Pio Pico, my cousin? Sí, welcome, Don Pio. Gracias, señor. Tell me, what is this delay? What caused this irregularity? No one knows, señor. And Padre has called us all here in the church before the wedding ceremony could be started. Well, it is most irregular. I do not like it at all. I shall make a protest. Oh, wait, Don Pio. Here comes the Padre now. Señorita, señor. My children, it grieves me to tell you this. I have just spoken with a messenger from the governor. There is a law. I cannot marry two people unless both are citizens of Mexico. What is this? Don Enrique Fitch is not a citizen. And the governor has forbidden the marriage. Well, that's unfair. He said nothing about it before. Oh, querido mío. Well, it's all right. We'll fix it some day. Caramba, this snake in the grass, that viper. He has done this because he himself is a disappointed suitor. He shall pay for this humiliation. No, Don Pio. He's right. If it's a law, he is right. You may have to wait a few days until I can become a citizen. A few days? Señor, you do not understand. It is the governor who can give the citizenship if and when he likes. It may take weeks or months or forever. Oh, no. No, Don Pio. But what can we do? We must do something. See, and we will. Don Enrique, is your ship still at anchor in the harbour? See? Then I have it. Come with me. I have a plan. It's my windows. Sí, querido. But you should not see. We are not yet married. Oh, Enrique. Oh, my darling, querido. Come, you must not cry. But tonight, even now we would have been married, attending the wedding feast. I know, but it's going to be all right. Come, now is not the time for tears. There's much to be done. Done? Sí.  Sí. Sí, but, querido, it is impossible. I cannot do it. Not do it. You can't read a mirror. You don't mean that. No, you must understand. My father, he would never approve of me running away with you. He would never speak to me again. I think he would, especially if Don Pio explained it to him. But the governor, he would arrest you. By the time we come back, all will be forgotten and forgiven. Don Pio will see to that. But, but Enrique, this is not right. My running away with you, not married. Will be. Will you not be with me? You'll sail with my friend Captain Barry and his wife. In their ship. I will sail in mine. And we'll meet in South America and be married there. Oh, I'm afraid. But, my darling, you want to be my wife.  My life was nothing before I met you. I can remember nothing. You were all that makes it real to me. Josefa, then we will not wait. We will go. I'll give you courage, little one. See, when I am with you, I do have the courage. Everyone will say that crazy American, he kidnapped Josefa. And nobody shall blame you. But they must not blame you, Enrique. They won't. When we come back happy and safely married, no one shall be angry, but only glad for us. Josefa, it's not right to thwart a great love like ours. We were meant to be together. Always. See. See, querido mio. Always. Then you'll go. See, I will go with you. And we are more. Bueno. And pack a light bag right away. Don't fear we'll come for you in an hour. Tonight? In an hour. Let's not allow another day to separate us. No. Not another day. I will go, Enrique. I will. Then this is goodbye. For a little while. I shall only be able to watch you from the deck of my ship until we reach our port. I shall be with you in my heart. Querido mio. And I with you. Hasta la vista, Josefa. Enrique. Enrique, wait. Goodbye, my love. For a little while. When you think of the title insurance and trust company of Los Angles, think of the word protection. For protection is the essence of both of the major types of service provided by the company. Title insurance service is your protection against loss of investment in your home or other real estate because of defective titles. The company issues various types of title insurance policies to meet various needs. Each policy specifically states the scope and kind of protection it provides. Trust department service is for the protection of the assets of your estate generally, either during or after your lifetime. Expert estate planning to prevent unnecessary shrinkage of estates through tax, probate and other expenses and experience the state management for the conservation of estates is available to you through this, the oldest trust company in the Pacific Southwest. A letter, personal visit or telephone call will bring you complete information without obligation about any of the protective services offered by the title insurance and trust company of Los Angles. Upon the return of Captain Henry Fitch and his bride, the troubles were quickly smoothed over and all was forgiven. So closed a romantic chapter in California history. But more exciting chapters were to be written into the history of the Carrillo family. In 1827, Carlos Antonio was sent to the Mexican Congress to represent the province of California. There, one of his features made him famous for what was published in book form. It was the first book by a California honor and has been regarded as the finest defense of the California missions yet published. Later, it was the turn of Carlos's young brother, José Antonio Carrillo to take his place in the Mexican Congress. José was the firebrand of the family, the politician Par excellence, a vehement supporter of every measure which might give California home rule and thus separate the government from Mexico City. And so it was that he approached his brother Carlos in 1837. What Carlos? This Alvarado is not legally governor of California. This Alvarado, as you call him, is our kinsman and a fine man and he is governor, a Californiano governor at last. That is what we want. But he is not, he is governor for the northern section. They like him, but he's not governor for us here. For he wishes to move the capital back to the north when it rightfully belongs here. But that is such a little thing. It is not a little thing. If the capital is moved to the north, they will forget us here. Leave us without adequate government, you know that. Perhaps, but Juanito is the governor legal. But he is not. Our nephew is no longer governor. He got his title by a revolution. The Mexican government is a point they knew legal governor. Who is you? Carlos Antonio Carrillo is now governor of California by order of the Mexican Congress. But Jose, I do not want to be governor. Nonsense, any man would like to be governor. Why did you not get them to appoint you instead of me? You would rather be governor than me? Nonsense, you deserve it. This weight is practically the same anyway. You, my brother, are governor and I am your advisor. Oh, Jose, you and your plots. First, you plot against governor Victoria. See, and run him out of California. See, but always you want the Californiano governor. Now that we have one, you want to change that. See, so that we may have a Southern Californiano governor. And I am the one who must bear the burden. Not the burden, Carlos, the honor. Just think, tomorrow he will take the oath of office. And Carlos Antonio Carrillo will go down in history as a great governor of California. But what about Juanito? What will he do?  No, perhaps not. But we will beat him. See, let the tyrant Alvarado storm. He shall be defeated by Governor Carrillo. But Alvarado was not defeated. Instead his army swept down in Los Angeles, swept Governor Carrillo's forces on to the south. No battles were fought. But finally they met on the plains of Las Flores, near Oceanside, and fought their fight at the conference table. But Juanito, my governorship is approved by the city of Mexico. That may be, señor, but I have not been officially in front of it. And hence I must retain my rights as provisional governor. Oh, but now Juanito, you must... Don't call me Juanito. Oh, I am sorry, Juan... señor. I cannot seem to forget the fact that you are my young kinsman. He will forgive me. See, of course, don't, Carlos, but don't say it again.  After all, I am the governor. No, I am the governor Juanito. Señor, if you use that word once more, I shall sound the charge wipe out every man of your army. Oh, dispense me. I am sorry. You just slipped out. Well, see, it does not slip out again. Because I am the governor. Very well, very well, we are both governors. Let us start from there. You govern the north. I will govern the south. Is there any reason why we cannot split the province into two sections, eh? Have the mejicanos given you authority to do that? Oh, no, but what does that matter? If we can settle this between ourselves? Well, so much the better. No. But I have sent to Mexico to explain my position. And I would not be surprised to learn when my messenger returns that the city of Mexico will declare me legal governor after all. Oh, well, señor, if they do that, well, that would be all right with me. Well, I have never wanted the position anyway. But until they do, we must work out something between ourselves. Very well, don Carlos. I am willing to listen to reason. Bueno, bueno, Juanito, then we shall... Ramba, you did it again. Juanito. Juanito! Madre de Diosito is the finish. At the end, I will stand no more. This conference is at an end. And now, señor, I shall see that you are to be governor no longer. What Juanito you... Ramba! Negotiations were interrupted by Alvarado's anger, but in the end, a truce was called. But now, support for Don Carlos Antonio's governorship cooled, and soon his own men gave up the fight. For a short time, Alvarado jailed both Carlos and José Antonio, but quickly they were sufficiently back in favor to receive his grant of the island of Santa Rosa. As the years went on, both men assumed important roles in the progress of Los Angeles and Santa Barbara. The incorrigible José Antonio continued his plotting and was a leader of the revolt against another Mexican governor, Micheal Torrena. And again, in 1846, one revolt against the American forces of occupation fled. General José Antonio Carrillo was in the thick of it. It was he who worked out a ruse to use against Stockton. When the American landed at San Pedro in an attempt to recapture Los Angeles, José called Benjamin B. Wilson to him. You sent for me, General Carrillo? Sí, Don Benito, I want your help. But I am your prisoner, señor. Sí, no matter. You wish to see this war ended as soon as possible, just as I do. Very well then. You will help me? Well, if it will end the war, of course. Bueno. Stockton is just sailed into San Pedro Harbor. Soon he will land and march towards Los Angeles. But you are to meet him with terms. And what are your terms? That he may occupy the coast and the ports while we are left unmolested in the interior until the end of hostilities in Mexico. Then in the treaty conference will be decided the fate of California. Fair enough. But what makes you think Stockton will accept any terms? I have provided for that. You see over there behind the hill, horsemen kneeling about. Good Lord. Why, by the size of that clouded dust, there must be a thousand horses behind that hill. Sí. And the comrade of Stockton will realize that too. But General Carrillo, there aren't that many horsemen in your army or in the whole of this area. No, but Stockton doesn't know that. You see, I have a hundred horsemen there driving a thousand wild mustangs back and forth from the harbor if we look like a huge army. And Stockton will be frightened into accepting our terms. Well, General, you have quite an inventive mind. You see, but this is no time for compliments. You must go. They will be landing any time now. Very well. But wait, General. Have you looked out into the bay recently? No, I... Caramba! What is this? I'm afraid your trick has worked a little too well, General. It looks to me like Commodore Stockton has hoisted sail and is putting back out to sea. Jose's roots worked too well and it might have saved considerable bloodshed. But the Carrillo family adapted themselves to the new American life which took root in California and kept their place as one of California's first families. Their high position in California history was well illustrated in a simple service which took place at the Mission Santa Barbara in the year 1852. Just two ashes, dust to dust. And so we place Carlos Antonio Carrillo here under the altar of the church he served so well. It is due to men like him that this land has grown great. For it was he and men like him who founded not only a new province but a great and gracious culture which is our heritage. May the Lord bless him and keep him. The heritage of greatness, which was Carlos Antonio's and Jose Antonio's and Jose Raimundo's and all of the Carrillo families has been carried on through succeeding generations. Carlos's son Pedro was a leading figure in Los Angeles and Santa Monica life. And today, a great grandson of Carlos Antonio, Governor of California, is also famous and well-loved figure of the state. Leo Carrillo, famous as a motion picture star, respected as worthy successor to the heritage of his family in the whole California. He's been preeminently active in civic affairs and in promoting projects to keep alive the beauty and romance of that graceful era. It is he who offered these words which glorify the days of the old missions. Out where the poppy nods its head like a tiny mission bell where the pottery walks through the mustard stalks along the old Camino Real. Silent milestones mark the way telling tales of an old tradition relics of a glittering age indelibly set on history's page the last of the Spanish mission. Ladies and gentlemen, a special message from Frank Graham. Our thanks to Leo Carrillo for the use of his fine little poem and for help with the tales of the story. And our thanks to you of the radio audience for your friendly interest in our programs. With this broadcast, the romance of the Ranchos concludes its current series of dramatic stories of early days in California. All of us in the cast and our sponsors the Title Insurance and Trust Company of Los Angeles sincerely hope that you've obtained both pleasure and profit from listening to them. And that through this closer acquaintance with our Southlands exciting and colorful history you have enjoyed, as we have a new interest and a keener appreciation of living in Southern California. And now before going off the air Title Insurance and Trust Company has authorized me to offer all you good friends a parting gift. To all of you who would like to have it the company will send you with its compliments a copy of its colorful early California Rancho map. Now I've seen this map, in fact I have one framed in my damn at home. And every one of my friends who've seen it has wanted one for himself. So I know you'll want one. It's 18 by 20 inches, printed in full color on heavy paper, just right for framing. It shows the boundaries, the streams, the hills and valleys of all 52 and the original ranchos that comprised what is now Los Anglos County. For your copy of this Rancho map just send the postcard or letter to the Title Insurance and Trust Company of Los Anglos 433 South Spring Street or to me here at KNX in Hollywood. Be sure to write your name and address plainly and address it to the Title Insurance and Trust Company of Los Anglos 433 South Spring Street or to Frank Graham KNX in Hollywood. Now until we meet here again this is your Wandering Vaquero speaking for all of us and saying Hasta la vista, señoras y señores. The romance of the ranchos has been a presentation of the Title Insurance and Trust Company of Los Anglos featuring Frank Graham as the Wandering Vaquero. The stories have been dramatized by John Donkel and produced by Ted Bliss Special Music Arranged by Gaylord Carter. Bob LeMond speaking. Good night.


I think we can start. So, we are looking at the SIP trapezoid and we are discussing the forward invite structure which was there. So, I will actually move ahead from there. It is like there is a one public address which never changed. So, to and from actually is for that, but the contact which is at that point of time when this invite request is being sent where the actually that person is. So, if you will actually notice in the contact field after SIP colon whatever is the user name at the rate then it is for Alice it is PC33.Atlanta.com because her soft phone is actually being given that particular DNS name at that point. So, that is the actual location of that entity is at that point of time, but actually from outside because she might keep on changing her IP addresses. This can happen dynamically she may plug in the phone at some other place might get a different name. So, this cannot be used as a universal ID and when she is telling for example, a visiting giving a visiting card to you she cannot start how will she will modify all the for all the visiting cards which is already been distributed. So, there has to be a universal naming which does not change. So, that universal naming is related to domain name and this contact name will also be there with what we call location server or register. So, whenever she will change this she will actually for your display whatever is your public URI say URI corresponding to that this will be the another URI. So, this will what will be registered with the location service. You do not know for example, about the Bob Alice does not know what is a Bob's current contact. So, that is the whole problem that is why invite has been sent which goes to SIP proxy SIP proxy sends to the proxy in the domain of where the Bob is there. That proxy then talks to the location server or register finds out for this particular public URI SIP URI of Bob what is the current contact and once it knows the current contact it actually it makes a invite request is sent to that contact URI machine and while returning back then the Bob will be simporting up his contact. So, both Bob and Alice will be knowing their actually current contacts and they can do direct peering on that basis. They can even do direct signaling after that if the signaling has to be routed through proxies it has to be mentioned explicitly when the invite request is sent. They can directly contact unless in the request setup invite request there are certain header fields which have been added. For example, in the forward invite first thing you are putting was via every SIP proxy was putting a via entry. So, by the time it reached to the Bob there were three via entries which was there in our case. Now, this via actually tells when the response has to be sent back this should not be sent back directly it has to be via this. So, whatever the top most via thing the response will be always sent to him if there was there were no wires the response would have been sent directly to the contact which was there in the invite structure in that request. So, that was explicitly done actually there. When the Bob will respond I am now going to come to that response structure because they are they are I think quite certain settle things which I was also not clear earlier. I realize that the way it has been structured is not that simple and then of course it is using its own kind of a layering structure for a specification it does not say how you are going to implement, but layering structure which has been identified also tells how the software will be implement. So, this also typically use what we call a four layer structure for implementation. So, I think today I will first of all go with the response. I think I have already finished all the fields which were there in the invite request nothing has been left. So, response thing we have to look at and then of course we will move over to that particular layering which is used inside the CIPA what you call entities. There can be many CIPA entities and then we have to actually understand I have been talking about the state full and state less proxies they are not actually there are four entities technically I was not explaining about state full proxy can be further split into multiple things. So, we have call state full we have transaction state full and we have what we call B to B user agent B to back to back user agents actually. So, that also can be there and they are very minor subtle differences, but each one of them actually will have a different capability all kind of elements can be there usually most of these things are also happening even in other designs which are proprietary not CIP based, but they take a different form. The same thing must be there with the CIPA same thing must be there even Google talk some of them they may not be implementing or functionalities have been shifted names must have been different, but architecturally yes this is a very generic structure and this has evolved over time earlier RFC in this RFC actually has some differences because of this. So, coming to that thing what so the response which will be there and I think this is the CIPA trapezoid which we are talking about. So, the invite was sent in this direction and each one of them added their own via headers. So, first one was added by this second one by this third one by this there are three via headers which were there. So, there is a thumb rule that most of the fields will actually be copied when the response will be generated most of the fields will be copied back into the response. So, this example currently I am given example later on I will give the specification for the request and response structure itself there is a formal specification being given. So, usually it will be look something like this. So, this first line in the response will always start with this thing the first thing will be CIP usually it is a character case insensitive, but machines are expected to always put capital letters the way it is done with STTP also. This is a literal string it is not a number while in STTP case it is counted as a number, but that does not matter as far as the implementation goes, but conceptually that is a difference they actually have kept lot of things borrowed lot of things from STTP in this case. Now, there will be always a space one space there cannot be two spaces there is has to be exactly one space character. So, a space character cannot be used inside the strings that is very important here if it has to be it has to be escaped escaping I think all of you do understand or not all of you must have used latech at some point of time for your document processing system. So, latech has a very nice character this one this is a control character you want to type this character in the latech how you will do that is there a way to type this character how that will be done. Dollar is for some mathematical is servicing if I want to write equation. So, this will go in mathematics for that purpose suppose I want to put this string itself should be visible in the text how you will do that you are writing a book on latech where you want to explain how to write a math thing. So, you have to put this as a character, but the moment you put it it will write a math equation a is equal to b plus c it will write this it will not write this thing how you will get this dollars we have to use a escaping sequence. So, there is a special character which has been defined which is this if I put this character just before this the special meaning of this is lost this also has a special meaning. So, I can also put this. So, these are now literal strings. So, these two combined together when they will be passed will be now you will see something like this is what is escaping, but the problem is when this character itself has to be shown then I put and their backslash it removes a special meaning which is attached with this new line no this is not a new line in case of latech. This is a new line these are basically you are removing what we call you are escaping the earlier character otherwise you cannot print this it is not you check it is a escaping character it is not possible it is been used for that purpose. Well a very simple thing like you have math mode you put like something like this begin begin is typically slash begin math I think something like yeah and then. So, all these are a special characters they always start with this that is why it is a special thing, but this itself can be escaped by putting just one backslash before this that new line I think which you have to certain places actually it is being used I will tell you where especially if you want to write out what we call the text based configuration file in unix. So, this single backslash is also used as a what we call it is only breaking in a physical system or while you are doing c programming, but actually it is considered as a one single line. So, one single large line can be broken and when written into a dot txt file it is being written as whatever you are writing slash whatever is slash whatever is slash now when the machine is going to parse it. So, this is a b c d it will actually read it as a b c d new line like this. So, sometimes you require for example, when you are implementing print types and other thing and lines become too long for the messages then usually you do it that is again a common use again that is a special character there in this case, but that is within a string. So, when you are doing a print f and you have to print this particular thing then there is again a problem. So, you use a print f command and you put this then there is a problem actually. So, when you want to print this itself you have to again do escaping. So, escaping is a pretty good notion in fact HDLC when I was teaching I have talked about this escaping. So, what was that escaping thing which I thought they should not be continuous because 0 6 1s and 0 is the start header 0 6 1s and 0 should not or 6 continuous 1s should not happen inside this string. So, I implemented a bit stuffing. So, that is a escaping actually rule after every 5 1s I insert a 0. So, even if there are only 5 1s in actual data n is 0 still I am adding a 0. So, that why on the receiving side I can simply remove it same rule also applies here. So, certain characters control characters cannot be transmitted in the strings which you are doing they have to be escaped otherwise you cannot interpret. This infect also happens even your STTP transport or in XML schemas where certain characters actually have a special meaning. I think another character which you remember is this XML schema. So, I can put a tag I can close a tag now I want to put this itself actually inside as an argument then what I how I will do it. There is some field and this is only the literal thing this should not be interpreted by XML parser. Similarly, there is a character called M percent, but when you use an STTP you always write this thing as something else which comes here I think something like this is there I have forgotten that. So, we use A M P semicolon and something else here there is some initial command initial character this 4 characters 5 characters actually represent one single character. Sometimes in the URL which you have been actually using you must be using percentage 20 F or something you must be seeing in the URL that actually is a single character, but that is URL encoded. So, URL encoding is also there is an RFC on that. So, all control characters which have a special meaning are converted to something else and the reverse side again reverse conversion takes place and that is how in your file names you can still use a space in unix otherwise whenever you press you put a file name that is a separation between two arguments, but file name can actually have a space. So, I give you a file which contains a b c there is a space there x y z when I will do l s usually you will see a b c x y z you will tend to see these are single two files these are not two files, but now you want to do a v i editor you do a b c space x y z you cannot edit the file because the moment you see space v i will assume there are two arguments it is not one argument. So, whenever you have to do a v i editor you have to use for editing you have to put a backslash and a space and then it will be taken as a string. So, that control functionality of the space has been now about it the whole thing is taken as a string by v i editor. So, this is I think in computing is pretty common same thing will be required here well I just wanted you to appreciate what the escaping is well there are lot of ways everybody does it all the time it is being done unknowingly or knowingly. So, the first field will be this and then of course as I told that three guys have already added the v i headers. So, I am actually putting all the three of them. So, again this header must be having a description it is as per that format it says the one to whom you are going to send back the response is a C 2.0 compliant proxy it is going to use a UDP transport that is what has to be used when communicating back and the guy who has inserted this or where you have to send back your response first is this. So, you remember that this one was a CIP server of block C dot com. So, what has been informed to this guy is when you send the response back send it to this person and it actually will remove this particular v i field when the response will be moved further. 200 and 200 is for the machine this is interpreted as a basically the first field will always give version number is a fixed format one single space this is what will be fed to the machine or the automata which is implemented there as a software or a program will be understanding this particular thing and based on that finite state machine will change the state. This is for the humans machine will not interpret what is written here you can even write in Hindi if you wish that is permitted you can actually write that is also permitted remember I have escaped the spaces and you have to actually set a header field in this case which is a I think except language colon h n that is possible. So, a machine is not going to read it. So, does not matter for this is a UTF 8 remember all encoding is UTF 8. So, any language of the world almost all languages actually have UTF 8 encodings can be used for transactions. So, it so far I think I have not seen anything in except in certain countries where English is not being used commonly they actually do the encoding in their languages, but in India we jump somehow I have been following only English, but in the variants might actually be existing, but I think SIP server India nobody manufactures we mostly built on whatever is on the open source some small small companies, but they are not focused on the English in the aspect actually. So, most of the engineers who are going to manage they already know English maybe after 10th class they have stopped reading Hindi after everything is in English actually, but that is technically possible the provision has been made. Basically it is mostly because of China, Japan, Russia and then of course, French, Spanish countries, language people which are there English is not everywhere English is not a very prominent language by the way, but somehow because US build most of things have been done first English is there, but because it has to be also become popular all across the English and French you will always find that everything will have two variants although I think Hindi is the third most speaking biggest speaking language largest number Chinese first I think then French or something or French is I think very big lot French and English Hindi comes I think four fifth something somebody was showing me the list, but we still do not have implementations in that, but we do now permit your URLs for example, the when you are going to browse you can type in your URL of your browser in Hindi that is technically possible Firefox permits that in UTF 8 and that will be resolved by DNS and you can actually go to a site. So, I have not checked may be Google might be actually providing a domain name in Hindi for Google. So, you can try that out if you wish you have to check with them, but multilingual domain names are now feasible because everything has to be in UTF 8 all standards have been but this is also is in UTF 8 because of this it is not ASCII character set only thing this particular thing has been specified this particular thing has been specified this can be in Hindi does not matter it is a UTF 8 string only key words now has to be in English because they have been specified freeze that you cannot touch for computer language computer does not understand language for emits a string is a byte code. So, this particular byte sequence means this you are building up FSM based on that. So, in fact lot of when you are actually going to build up a machine you write a software you do not remember these whole characters usually need not you can convert this character to only whatever is required to identify a state variable that is it. So, this will have typically a semicolon now remember if it is semicolon it is not a separate value this is the header field this is the value values will always be separated by comma if they are multiple values which are existing for a header field semicolon is nothing but is for this particular value itself there is another attribute which is coming in. So, this semicolon and this branch will be some random sequence I actually have mentioned the same thing earlier also and this gives the IP address of where it has to go back second where field will be there. So, I think I can skip you can just copy whatever was written last time I have not even written a full string actually here. So, this will be now this one because this must have added it first this will say big box 3 dot Atlanta dot com semicolon here also is a semicolon remember I have even if I am actually writing it in a different line they all have to be in the same line they all have to be in the same line there is no CRLF in fact I should write another character called this is carriage return and line feed carriage return is whatever is your printer technically you are printing one by one the character you are here. So, carriage return is you are moving back to the 0 column and line feed is you are moving to the next line. So, CRLF technically you have to carriage return is one and LF is another one two characters actually. So, different machines handle it in final system this is actually done in a different way where it is a end of line technically EOL we call it. So, this has to be there. So, in this case the end of line is not here end of line happens here. So, I should explicitly mention that this actually is word for key word, but I am using it for CRLF carriage return line feed. So, CRLF I am representing it by this. So, it will also have a some branch number which is assigned by that particular machine similarly there will be third wire which is added by the sender this one single space is not these are not two spaces exactly one space that is a specification. The last one will say PC 33 at lenta.com it will also have a branch some random string received and then of course comes the remaining field. So, two field will be copied directly as this two field was what was it actually earlier it was Bob two field which was there first letter is always capital then all is small unless the word actually changes. Sir, this received IP means the next I have by. Is the IP of that particular server 10.blogs.com I think that is what it means it is so far I could not find out a spec, but my guess is it should be that there is no other purpose for this. So, this branch parameter identify the transaction between two people is a random string. It must be for identification of for transaction. This is between the proxy and the Bob in the client for Bob. This particular one between the proxy second proxy and the client this is between the two proxies this is between the first client and the proxy. So, this is basically it for identification because you might be issuing multiple things for example, multiple invites. So, when the response comes back you have to figure out it is for which one. So, far session has not been in fact there are many parameters which can be matched together, but what happens you need not go to the bottom thing and then actually match all the entries there you can just match the first thing here itself. If this thing matches then only you go down further. I think then my interpretation has to change because I could not locate any interpretation in the RFC. So, far is a huge document anyway I have only done it partially yeah there was no received I think this is then this must be the IP address of the machine which must have received who is responding back must be for that. So, that guy can figure out whom actually he has sent and then match with that as well as the branch now whatever is the random string. I think that must be the logic it does not bother there is a packet or circuit. It is a message transfer between at the application layer. It does not know about the path there is a UDP connection. How the UDP packet is been commuted through the actual physical network is the headache of IP layer. My guess is that when the response is going back we have not to consult a PRS server and all this thing that why they are using it. This should be as a proxy number. Again when they are sending back the response they will not have to consult a location server and DNS server again again. You need not to anyway have the DNS anyway DNS we do not bother we do not call it a SIP server or something. It could be the default gateway sir and in case it takes a shorter connections because the from the proxy to. We actually leave it a question mark and we can study SIP proxy and we will find out then we will discuss that. So, we are not clear and we cannot figure out what could be the meaning interpretation. So, leave a question mark and let us investigate that is a basis strategy. So, this I think I will whenever I will find out I will tell because I do not know how much I will be able to go through the proxy and where it is given. So, let us whatever concept we can pick up let us pick up those. In any way if you end up in implementing the software you anyway have to find it out. So, you have to read the full RFC and you will find it out. What is the meaning of this? I have not so far reached to the specification of wire structure. So, two field again will contain here the only difference is rest everything is remain same it is a bob angle brackets within which your SIP URI actually will be there. SIP URI also required all string has to be escape destring angle brackets cannot be used inside the SIP URI that is very important. You have to use all strings which are escaped strings whenever the URI has to be communicated and you cannot use angle brackets in your email. So, you for it is I think same way for example, I cannot have a something like this this email is not permitted because there is angle brackets because these are usually used to enclose the email ID itself. Even angle brackets are used for a special purpose in programming that is for actually templates. So, that is a new concept which came later on C earlier see it was not there, but current NCC actually specifies these templates which is a pretty powerful tool. So, I write the same code and I can generate a code for depending on whatever is my requirement for different things different piece of code. So, whatever was the SIP URI that SIP colon bob at the rate block C dot com and then you will have a tag. Now, this is something which is newly added and this forms an important part. So, remember two tags one which is one is in two one is in from and one is what we call call ID these three thing put together specifies a dialogue it is not a transaction when I send a invite and comes back. In fact, any response which is non one x x will complete the transaction is known as final response only one x x is a provisional response that is a non final response. So, transaction is over, but you might be doing other transactions ultimately you have to have a buy for example, as a transaction. So, all transactions which corresponds to same dialogue should actually have the same tag values in two tag value in from and the call ID has to be same that is how the association to the same call dialogue actually happens because the one guy might be making a multiple calls. So, when a message come it has to be associated to a call. So, this triplet is the core here to identification for the identification of calls. So, this tag value sub will be some random string from will be copied as it is whatever was there in the Alice when the things were actually sent I think I had Alice say colon Alice at the rate Atlanta dot com. So, what was sent by in the invite this tag will also be exactly copied from the what has been received in the invite. So, even if two different invites come and this guy by chance sent the same tag the call dialogue will be different this and the call ID these three uniquely identifies a call dialogue. This will be said call dialogue will be up till the time the whole call is over when the buy comes actually or a rare happens. Till the time they set up directly clear to be. No, even after that the dialogue will be maintained. Dialogue will be maintained till the time they terminate the. See, they may not root the signaling message through this thing proxies. See, once the call has been set up they can directly do signaling also then also call dialogue has to be specified. Termination signaling can be done after the initial set of unless report root has also been configured by this proxies. If at any point of time when the invite was sent one of the proxies is record root and puts his own address there then that will be maintained at both with the bobb will maintain it because he receives the invite. The same field will be copied back in the response Alice will also receive it. So, they both now have to do signaling only through that proxy because that is a record root for this particular call dialogue has been maintained mentioned in the beginning. Then the buy when it buy has to be sent for call termination has to go through that proxy. In current case the example which I am taking record root has not been inserted while forwarding the invite. So, buy will be happening peer to peer it will not be through proxy. If wire would not have been put even the responses could have been avoided and could have been sent to only the last wire which is this one. So, invite goes this way the ok comes in this fashion. Only problem in that case is if it is a call state full proxy it will not know the status whether the call is through or not through.  Transaction is state full proxy is a different thing transaction happens only between a client and a proxy. So, transaction is happening between these then a transaction is happening between these and this is a transaction user running here I will come to this particular structure actually and when the response comes back they keep on sending the response back. If it is a state less proxy this will not remember anything this whatever comes is simply forward it does not remember what it has forwarded when something comes back it sends it back that is it it does only proxy. So, I will come to actually that particular figure which is required to identify this thing. Then you will have call ID this is going to be same which was there in the earlier communication the invite remember this is a response there is no method being specified there because of this. Then c sequence this will also be copied from the invite. So, there was a method which came there was a corresponding sequence number this response as a result of when that method was executed. So, the sender will be able to figure out the response corresponds to which particular command when it will send a next command again the number will change. So, some command gets missed out it can figure out that I have not received the response to this particular command I have got for one I have got I have not able I am not able to get a response for two but got a response for three. So, it can figure out what particular commands have not been executed, but all final responses for all commands should arrive back. So, this sequence number actually helps in doing that actually. And then of course, this is contact which was not there earlier this is now what will be added. This will be telling that this Bob this will not be Bob sip colon Bob at the rate at Biloxi.com this will be where is actually current as of now is staying current location this where the peering will be done. And interestingly sip is not the only URI for telephony there is a TEL URI which is also used by a lot of people. So, sip also can be used to carry not only sip, but tell URI also, but then how those will interpreted is a different question. So, in this case 0.2.4 now I think from here yeah now I can get what has happened is this IP address has to be of the proxy from here I can guess this is not the one who is giving the answer back this for the proxy. So, it is only telling that when I received your the packet I received from this particular IP address when it is sending the response back and it is responding back to whatever IP address which will be resolved from here. So, it is technically possible that there is another machine which is running here. So, invite comes in this this invite was received from here and this has put a via entry for this particular one another machine setting the same domain. So, it will send the entry here response will be sent here a different machine because when the via entry was done this server 10 there is server 1, server 2, server 3, server 9, server 10. So, invite was received from this IP address was response has to go back to this that is what actually it means and the same thing is being copied back this is a copied back a stuff remember only this thing was added depending on from where you receive the invite request I think that is what the interpretation should be there cannot be anything else now. Again my interpretation is that only to avoid the lookup they are adding the IP address because if that has to be done then even this is not required you just put the via field. It should be there because if you remove this server proxy again you do not giving IP address. So, what path you have to do again you have to lookup on the you will lookup you will lookup, but you avoid time lookup you can put the IP address the only reason I can figure out. But then in that case why this need to be added back question is this this guy was sending the response back this person already knows from which IP address I got it this IP address is of no use to this guy no this guy will send to this proxy and that will remove this because this is. But why this need to be added only for Bob Bob is already when it got the invite that time you know what is the IP address when you are sending this messages for this guy is a response. So, this is only for verification purpose that in this domain I am sending the message back to you, but the response which I am sending was received to me invite was received from this route. So, I received it from here and this is where it is going to be sent back. So, you are sending a information and you are telling him that this is this particular thing was inserted when the invite was there by this proxy I think this is for this this is a very settle thing again. So, these two things can be different if indeed it is going to send this thing back to him then both of them will be same you are right then both of them this also DNS should resolve the same IP address, but I think the clue here is I think RFC specifically again even how the naming is done is also discussed server 10 probably must have been done intentionally why not only server dot block C dot com in the text. Server 1, server 2, server 3, server 10 it actually telling their multiple servers and when proxy is sending this must be this IP address IP address they have just put it actually 192, 0.2, 0.1, 0.2, 0.3, 0.4 that is what must have been done in the RFC even these namings are also so that people can understand they should not misunderstand this stuff they can make out lot of things through this mechanism I think this must be the reason. So, this is the fourth IP address which now even clarifies that this is the contact now PC33.Atlanta.com corresponds to 192.02.1 which is this particular client where Alice is there and then of course, I think rest is all state forward contact type dot 4 is for Bob. So, this Alice contact is not being copied here Alice contact came from that side Alice's contact come from the different side remember. Sir this 2 dot 4 is for Bob. It is for Bob is a contact of the guy who is sending the response that was the contact of the person who send the request this 2 and from field is not for the response because the response is not going back to the Bob and it is not from Alice. So, this that can also be one of the confusion this talks about the invite message this is corresponding to the invite which was sent from Alice to Bob and this response is originating from this contact. So, contact is the one who is from where the things are originating 200 is also specific that it is a response to that yes because remember these tag values and call ID 3 things become the call dialogue and for the call dialogue 2 and from is what is important this 2 and from is not for the response or the invite is who started the dialogue call dialogue is only one invite is one of the transactions which is happening inside a dialogue and this transaction will get completed when this ok will go back final response which one call ID exactly same this will be same number at the rate PC 33 dot Atlanta dot com. So, number which was there actually written last time it was it must have been I think this A 8 4 B something PC 33 Atlanta dot com. So, contact type in this case content type not contact is a content type content type this is a mime type specification again. So, this is again a session description. So, this basically what kind of call is going to be set up all parameters which are now being accepted by the Bob. So, Alice might have told I want a video call to be made and video will be with this codec audio will be with this codec or this particular options are there and now set up the call this guy might revert back I do not have a video. So, this SDP says no video only audio is going to be there. So, subset of that will be accepted and sent content type content length these are all standard thing. So, number of octets octets or bytes which are there and then of course, remember after each one of them CRLF is there that is extremely important after this whatever is the character. So, may be say 131 I have written here some number another CRLF even if you do not have any payload any content attached even then this CRLF has to be there even if it is nil if you are going to put content length is equal to 0 then also this carriage return line feed has to be there. So, if you are actually creating through a VI editor you are trying to build up a header file for a programming application never forget this because other side will not accept it in that case. You can try this thing if you wish for HTTP that is taking even for this I think it should be possible do a telnet and do a telnet to port number 80 of a web server do not do SSS. So, telnet and do not give a user your name need not be given. So, telnet to a machine is space 80 you can even specify the port where the telnet has to be done by default I think it is 23 by default I think it is 23 telnet is 23 FTP is 21. So, most of the people actually do not know that they can change the port. So, they do a telnet space and the machine where you want to do a login, but telnet is not a secure protocol it is a clear text transport actually which is used and then you can specify a port number 80. So, you do a telnet to a proxy 80 CP connection will be set up and suddenly there is it will not ask for login password because there is no challenge in that is not a telnet server running on the other side there is no telnet D-Demon on 80 port it is a web server mostly Apache or may be something else, but then you will see a line then you will write get whatever is the first command you just type it out nothing will happen once you press one enter you have to write down all the header fields and when the center is made then only the header will be interpreted by the machine on the other end because what is happening is technically for HTTP I am creating a byte pipe which is a TCP connection between two machines as you are pressing characters these characters will just be there is a algorithm which is used to keep on waiting for certain number of characters then it will be put in the frame will be transported this will keep on receiving the character, but will not start interpreting till it finds out two CRLFs together when it figures out their two CRLF fields together header is finished now let me parse it and after that once after the parsing will figure out how many characters it is supposed to receive after this then it will keep on receiving those many bytes then the HTTP request is all over because mostly HTTP is now using persistent connection. So, same TCP connection now we can be used for another HTTP request earlier days for every HTTP request separate TCP connection response comes back TCP connection closed next one again you do the same thing. So, persistency was implemented later on actually so it becomes pretty fast you only have to do it once TCP connection. So, that overhead was actually removed. So, same thing is concept is also used here is the length of the content which will start from this line on word if it is 0 there is nothing after this is the end there is no end of file in your Linux systems. So, mostly it is based on Linux systems so there is no end of file character your Microsoft I think earlier file systems were actually using an end of file character at the end of the file here purely it is based on how many bytes have to read from the beginning it will read those many bytes file is over so structurally it is same actually. So, this is what will be typically the response let me quickly close through the complete transaction. So, for example, now what can happen is this guy is sending. So, first thing there was 100 which was coming trying this also will receive 100. So, when the invite was sent this can actually send something like 486 also I am just giving an example it is busy here this is one of the codes I will specify which part of a 1 x axis for what 2 x axis for what 3 x axis for what. Now, this 486 is not received by this person this is sent by Bob because Bob may be talking to somebody in that case this proxy can actually decide that I can now try making a call to a voice mailbox. So, this will typically use for those kind of applications if you want to change the parameters of the session in between you will again send another invite, but now your sequence your tags and call ID still will be maintained same. So, that invite is a reinvite because it is not a fresh value that fresh value states are being maintained by these two entities. In fresh invite in this new reinvite basically it can send the new parameters new SDP if it is acceptable you will get 200 back and this new invite need not be sent via proxies this can be peer to peer that is important unless that record root thing is being configured in the beginning and then of course it can send 488 which is not acceptable that is what is the meaning. So, remember these strings are application is specific these are not hard this can be rewritten by you machines will understand only these codes this is only an interpretation of that for the humans. So, you can write it in Hindi it is ok. So, these are not synced sacrosync these are sacrosync numbers. So, if this comes the call will remain with the older whatever agreement which they had actually this typically happens if the bandwidth of this channel for example, improves there is a bandwidth estimation bandwidth becomes better you can say go for a better code or better quality video for example, you can again agree, but the other guy does not have the capability or bandwidth goes down then you can downgrade yourself.  It is only for signaling path. It is only for signaling path, not for media. If you want a media proxying or media gate wing in between, you will not actually, you will first of all what we call back to back, you will create two trapezoid in that case. That is a typically the structure. This is your media gate wing. So, signaling happens in this fashion. That could be one option and then media goes in this fashion. There is another way of signaling. This guy wants to go through the media gateway or maybe there. So, it will actually have a media gateway to do the signaling to this guy. Then it will do a signaling to this fellow. It is now doing a tricky thing. It is now telling him that this is the end user and making him peer to with him. For on his behalf, now this is a media gateway control now. This is this mega core. Even this can be used, not an issue. For him actually now it is peering and then there is a bob and bob will start peering with this. So, one signaling path is this. Other one is between these entities. That is another way of doing it. This is what we call back to back user agents, B2B UA. So, you have a user agent server here, user agent client here sitting and they are back to back funnel together and you can also build up tricks. For example, for signaling you can have B2B UA, but you might do media transport directly that is also possible.


Hi, in this video, we're going to take a look at the underlying data for the EPA's flight tool. These are data on greenhouse gas emissions from facilities all across the United States by facilities. I mean power plants, waste processing centers, factories, and so on and so forth. So I highly recommend you click on this flight tool to explore the database in another format. If you click on that, you'll go to their web app. So this is the flight tool here and here it's a map based overview of the data. You can zoom in on different localities and see where these facilities are located and information about them. You can also filter by different facilities and variables and so on and so forth. So go ahead and check that out. However, what we're going to do here is we're going to look again at the underlying data. We're going to do our own thing with it outside of the web app. And we are going to ultimately find which state has the largest amount of emissions from facilities. So this is not emissions from the automotive sector or anything else, just from facilities. And along the way, we're going to look at histograms. We're going to see how to calculate the mean and the median, and then ultimately how to summarize all the emissions within each state. So let's get to it. So we're all familiar with importing the data. We've got that those lines of code here, except there's one difference now that you may not be familiar with. And that is the skip rows argument. So why do I have skip rows here? Let me explain. We take a look at the underlying CSV. Our data frame or our table doesn't really start until row four here with the column headers and then all the data below. We've got three superfluous lines here that really aren't part of the data frame at all. And we don't want to include. So we just need to skip those three rows. So, and this makes this incredibly easy. We say skip rows equals three. So we skip over those unnecessary lines there. And here highlight this, this highlights the importance of taking a look at the CSV file before doing the importing just to understand exactly what is in this in this data file and you can open up the CSV files and in Google Sheets or Microsoft Excel. So once we have this imported, let's go ahead and take a look at the size of this data set. And one handy function to do this is shape. And all the shape gives us are the number of rows in this data set and the number of columns. So 15,386 some odd rows, rows here are different facilities. We've got 66 columns. Furthermore, we should take a look at what the columns are exactly. So let's print out the column names here. So you've got facility ID facility names, city, state, etc, etc. And one really important variable here is total reported direct emissions. So we're going to focus on that, although there's a lot of other interesting things here to particular the industry type so what type is what what form of industry is producing these emissions, lots of other useful things here. So, let's get down to it let's start by finding the histogram. So, with a histogram we want to make sure that the data that we plot and our visualization in the histogram spans from the minimum of the data to the maximum data at least needs to cover the span of the data. So if we want to find the min and the max. Let's just say GHG min. So we're going to find our minimum total reported director missions. We just use the min function. Very easy. We'll do the same thing for the max. And let's print these results. We'll say min is GHG min and max is GHG max. Our direct emission values for all the facilities span from zero to some really large number here so what is this about 20 million more than 20 million. So very large number here. So let's see what happens when we make a histogram of this. So we'll call our data frame. And one easy way to make a histogram is through pandas we just say histogram dot hist. And we give it the column that we want to make the histogram of this is in this case total reported director missions, and we'll run this.  And what is done is it's used some, some predefined, you know, rules of thumb to, to make adequate bin sizes of our histogram here. So the histogram is counting the values that fall within specified ranges. And, and then plotting those frequencies as, as bars. So this is essentially a, a frequency table represented graphically, where the categories are just different ranges of the quantitative variable. However, when we use the default method here, we don't know what those ranges are. And that's a little bit problematic. We're not sure, basically what the breakpoint is between this first bin and the second bin. We don't know where this, where this stops. So it's good practice to manually specify the number of bins that you have. So we could do this fairly crudely and we could say one e to the seven. Seven, seven, one e to the seven being 10 million up to 20 million. Oh, but then we have to go up to 30 million, because our largest values slightly more than 20 million. So we can do this we'll have three bins, we've got four values specifying the breakpoints between those three bins. And we visualize this and we see a pretty crude histogram. I say this is crude because we pretty much have all our values in this first, in this first bin here, and then a few values in the second bin and probably one value in this, in this third bin. So these bins are too fat we don't have a good enough resolution. And so we could go we could break this up some more we could subdivide it. So the tool here is the range function built in range will just give us a sequence of values from some integer to some other integer. So let's say, oops. So let's say 21 million, and by some step, let's say we want to go by, by one million. And we have all the list of values, going up in that increment. So this is a handy way to, to build these bins. If we want to have many of them and we don't want to manually specify the breakpoint between each and every one. So there we go, we get a much finer histogram. And we know where the breakpoints are we know this is going from zero to 1 million, 1 million to 2 million, 2 million to 3 million and so on so forth. So that's the histogram, and it's telling us the spread of emissions from the facilities. In particular we see we've got a lot of values that are close to zero, very few values that are really really large. So this is what we called right skewed is an example of a right skewed histogram. Let's go ahead and calculate some measures of center. So what is the average level of emissions from these facilities. Let's do this in a couple of print statements. So if we want to find the mean, also denoted X bar. So it's going to be equal to our quantitative variable, G H GM and this case is total reported direct emissions. And we just say dot mean calculate the mean. So a good practice to include units or units here are millions of tons of CO2 equivalent. So MMT CO2 E millions of metric tons CO2 equivalent. It's a lot of give us the mean, and let's compare this to the median. Instead of the mean function we just have the median appended on there. And this doesn't have the notation X bar the median is just the median. Let's run this. You see that our mean, but 388,000 are median 65,000 or so a lot less. What this indicates to us with the mean being much larger than the median is that the distribution is indeed right skewed. In other words, this mean value of the mean gets pulled up by these much larger values up here. These are most likely outliers. So the mean is more susceptible to these outliers. The median is more robust to them. And that the median falls, you know, well within this first spike here mean somewhere up here.


Soon after World War I erupted in Europe, it became evident that the airplane was forcing a permanent change in warfare. By the time America entered the war on April 6, 1917, the airplane was well established as a military weapon. But the United States had only a small number of pilots and very few training planes. There were no bombers, fighters, or other combat-type airplanes. American air power ranked 14th in the world. Secretary of War Baker urged the nation to back the build-up of a vast air fleet. Congress rushed through a bill appropriating $640 million for the build-up of American airstream, and President Wilson signed it on July 24, 1917. A large-scale production of airplanes was initiated. Among them was the courthouse JN-4 called the Jenny. This two-seater was selected as the standard pilot training plane. The British-designed de Havilland-4 was adopted as the standard front-line bomber plane for combat. The famous American Liberty Engine was developed to power the DH-4, and it became one of America's greatest contributions to aviation during that era. 543 of the American-built DH-4 saw combat before war then, serving a dual role as observation plane and bomber. Not only were airplanes needed in large quantities, but men had to be trained to fly and maintain them. The Air War in Europe stirred America's young men. There was no shortage of volunteers. In the year following the declaration of war, over 38,000 of America's youth had volunteered for flying training with the Army. Training them was a mammoth undertaking. Successful applicants were sent first to ground school for an intensive eight-week course. Then they began flight training. This was divided into three phases. Dual instruction, solo practice, and cross-country training. Successful completion of these phases earned the flyer his commission and the right to wear the wings of a military aviator. When state-side training was completed, the new pilots were sent overseas, where they were taught to fly combat planes. Although the first American flying unit didn't arrive in Europe until September 1917, some Americans had already flown combat with the British and French beginning in 1915. Many of them flew with the famous Lafayette Eskidrill. After the United States entered the war, many of these pilots transferred to the air service. The nucleus of the 103rd Aero Squadron was made up of former members of the Lafayette Eskidrill. The 103rd was the first American squadron to see action as a unit. The 94th Pursuit Squadron became the first American-trained flying unit to see combat. The 94th was the famous Hat and the Ring Squadron, later commanded by Captain Eddie Rickenbacker, who became America's top ace in World War I with 26 victories. More American squadrons joined those already committed to battle. As the intensity of the war increased, so did the involvement of the American air services. As an example, American pilots flew over 3,300 sorties during a 5-day period in September of 1918. Great battles raged, both in the air and on the ground. The Germans attempted to smash the Allies before the influence of American forces could swing the tide of the war. It took large concentrations of air power to counter the German efforts. The Allies planned an all-out effort to wipe out the large German salient at San Miguel. The battle plan included the first independent attack by the American Army, and it called for a large air offensive. Colonel Billy Mitchell was to command the largest aggregation of air forces ever committed, up to that time, to a single operation during the war. Flying both American-built DH-4s as well as French and English-built planes, the Americans and French enjoyed numerical superiority for the first time. On the opening day of the battle, Mitchell committed 1,500 planes. He proved his theories on the effectiveness of concentrated air power, as his aircraft entered combat on the third day of the battle. Bombing and strafing helped to demoralize German ground troops, and was a major factor in forcing the Germans out of the San Miguel sails. Mitchell's aerial tactics were repeated during the Musard Dawn offensive in late September, accomplishing the greatest single aerial triumph of the war. The Allied Air Armada fought off waves of Germany's best planes and pilots. The already weakened Germany was unable to launch a planned counter-offensive. The defeat of Germany loomed closer. By the end of the war, November 11th, 1918, 71 Americans qualified as aces, each credited with shooting down or sharing the destruction of five or more German planes. Their total score was 450 planes and 50 balloons. A few of the never-to-be-forgotten American aces were Lieutenant Frank Luke, Major Raoul Lufverry, and the ace of aces, Captain Eddie Rickenbacker. Six months before the war ended, an event took place in the States, which influenced the evolution of American air power. On May 15th, Army fliers inaugurated America's first airmail service. In the years following, airmail pilots established routes and a system of airways that are still being utilized. Many ex-military fliers wanted to stay in aviation, but there were very few jobs for civilian pilots. Some bought surplus Army planes and flew them anywhere they could make a dollar, carnivals, county fairs, exhibitions. These barnstormers often made money by taking passengers for their first plane ride. Some earned a living by stunt flying, a very dangerous business which left crowds fell down. Many of these barnstormers invested in bigger planes and helped develop intercity taxi service, the stepping stones to today's commercial airlines. During the 20s, fliers accepted many challenges. They strived to fly higher, faster, and farther. Builders began to develop better planes, engines, and navigation equipment. Record flights came rapidly. One was the cross-country non-stop flight from New York to California. After two unsuccessful attempts, Army lieutenants McCready and Kelly took off from Long Island in May 1923. Just under 27 hours later, they landed in California, the first fliers to complete a non-stop coast-to-coast flight. One year after the record-breaking cross-country flight, four specially built Douglas World cruisers took off from a lake near Seattle on the first leg of an historic flight around the world. 175 days later, two of the original four Air Service planes returned to Seattle to successfully complete the 26,000-mile journey. By the time the name of the Air Services was changed to the Air Corps in the mid-20s, Army fliers had set numerous records and continued to work for technological advancement. Cold weather testing improved the ability of men and planes to operate in sub-zero temperatures. New speed records were set in 1925 when lieutenants Side Betis and Jimmy Doolittle won the Pulitzer and Schneider Cup races respectively within a two-week span. One month after Lindbergh's historic flight in May 1927, another flying achievement was accomplished by two Air Corps pilots, lieutenants L.J. Madeleine and A.F. Heggenberger. Taking off from California, they flew a Fokker Trimotor monoplane named the Bird of Paradise, non-stop to Hawaii in 25 hours and 50 minutes. With their destination a mere dot in the Pacific Ocean, their flight demanded exceptional navigation, superb flying skills, and real courage. In 1929, Air Corps fliers established an unofficial world flight endurance record in another Trimotor Fokker named the Question Mark. Using a mid-air refueling technique developed in 1923, aerial fuel transfers were successfully accomplished 43 times, nine of which were performed at night. The Question Mark, commanded by Major Carl Spotz and including Captain Ira C. Eaker and Lieutenant Elwood R. Casada among its crew, stayed aloft for almost 151 hours, landing only after one engine began to give them trouble. The decade of the 20s is often referred to as the Billy Mitchell era. Following World War I, General Mitchell was the chief proponent of air power, and he strongly voiced the opinion that America must maintain strong air defenses. Mitchell believed that bombers would spell the end of sea power. He asked for the opportunity to prove the effectiveness of air power over naval forces. The combined war and Navy departments granted his wish and gave him the chance to prove his theories. On two separate occasions, U.S. airplanes carried out attacks on warships that were going to be scuttled or scrapped, including the powerful German battleship Ostfriesland. Mitchell's bombers sank some of the supposedly unsinkables, including the U.S. battleships Alabama, New Jersey, and the Virginia. Many years were to pass before the significance of these bombing tests was fully recognized, as witnessed the destruction of American ships of the Pacific Fleet at Pearl Harbor. The decade of the 20s spawned many pioneers in aviation. Some of the names high on the list of non-military aviators were Amelia Earhart, Wiley Post, and the Lone Eagle Charles A. Lindberg. Considering the distinctive progress in aviation in the 20s, it seems justifiable that many historians turned this period a golden age of aviation.


Welcome to the presentation of the STM32-G0 UCPD USB Type-C Power Delivery Interface. It covers the main features of this module. The UCPD units embed a PD physical layer of PHY with a direct connection to the configuration channel pins CC1 and CC2. The UCPD can be configured as a downstream-facing port, DFP in short form, or an upstream-facing port, UFP in short form, and also supports the fast roll swap protocol that enables swapping DFP and UFP states. In order to implement the protocol layers based on message exchange over CC1 or CC2, the UCPD offers a programming interface enabling software to receive or send message payload bytes. Requests to external DMA channels may also be used to automatically transfer protocol messages to or from memory. The block diagram shows the two important parts of the UCPD module. The register interface on the left clocked by P-Clock that is used by software to configure and determine the current state of the module. Messages are transferred byte per byte by means of the TX and RX registers. The PD physical layer that encodes and decodes bytes appends and checks the CRC and also manages the transmission of ordered sets. The application benefits are integrated on chip PD-FI, including RP and RD resistors. Dead battery mode supported, allowing connection detection at the peer device in a dead battery situation. PD message transmission and reception software is only in charge of handling the payloads. The UCPD controller is compliant with USB Type-C revision 1.2 and USB power delivery revision 3.0 specifications. Regarding the FI, only the CC signaling method is supported, so the Type-C cable is required. The reset and clock controller unit or RCC unit is in charge of resetting the UCPD unit by asserting the NP reset signal. It also provides the following reference clocks to the UCPD unit. P-Clock, which is the APB clock used to access memory mapped registers and USB PD clock, which is the main functional clock. USB PD clock can be pre-scaled in order to obtain the half-bit clock required by the by-mark phase coding. Note that for the timings called T transition window and T interframe gap, the clock frequency uncertainty should be taken into account in order to respect the timings in all cases. The UCPD module asserts clock request to the RCC in order to exit a clock gating low power state. This slide describes the pinout of the UCPD units. Pins UCPD-XCC1 and UCPD-XCC2 are the only signals to be routed to the USB Type-C receptacle. Note that the cable contains a unique CC signal connected to either CC1 or CC2 in the receptacle because the cable can be flipped. The UCPD-XFRSTX pin is relevant when the dual roll port protocol is supported. It is used to control an external NMOS transistor that pulls down the CC1 or CC2 line respectively, which is the way to request a roll swap. Pins UCPD-XDBCC1 and UCPD-XDBCC2 are used when the STM32G0 USB Type-C port indicates to the peer port a dead battery condition by connecting UCPD-XDBCC1 to UCPD-XCC1 and UCPD-XDBCC2 to UCPD-XCC2. The STM32G0 implements internal RP and RD resistors connected to CC1 and CC2 pins required by the USB PD specification 2. Detect a connection. Determine whether the cable is flipped. Determine the default available power as the current carrying capability depends on the values of RP. Finally, a unique CC pin, CC1 or CC2, according to cable flip, is used to transport PD messages. The unused CC pin may become the VCON pin, which supplies the power to integrated circuits present in active cables. In order to conserve power, the unused CC pin can also be disabled by programming the CC enable field in the UCPD-CR register. The UCPD is configured by software as either a downstream facing port or an upstream facing port. The DFP mode, assuming no cable flip, CC1 is connected to RP. The value of RP indicates the value of the default power that the DFP can source on Vbus. In DFP mode, assuming no cable flip, CC2 is connected to VCON. VCON is a 5 volt 1.0 watt power supply used to power devices within the plug that are needed to implement electronically marked cables and VCON powered accessories. In UFP mode, assuming no cable flip, CC1 and CC2 are connected to RD, which is a 5.1 kilo ohm resistor. Since the UCPD supports both DFP and UFP operation, the internal switches represented in the figure select the current configuration. When the UCPD is used as an upstream facing port, the dead battery feature enables the UCPD to indicate to the peer node that it needs to be powered. This analog setting is functional even when the MCU power supply is switched off. This default behavior is configured by connecting the DBCC pins to the respective CC pins. After power arrives and the STM32G0 boots, the desired behavior should be programmed in the ANA mode and ANA sub mode fields of the UCPDCR register, and then USB PD strobe bit has to be set to 1 in a CIS CFG register called CIS config. Connecting DBCC pins to ground disables dead battery mode. In this case, the peer DFP is unable to distinguish a dead battery state from an unattached state. The fast roll swap protocol swaps the roles of DFP and UFP. The default power source node becomes the sync node, and the default sync node becomes the source node. To request an FRS to the source node, the sync device temporarily connects the appropriate CC line to ground. This is achieved by external NMOS transistors on both CC lines. However, only one will receive the FRSTX pulse. The NMOS on the inactive CC line should be driven with a logic zero level using GPIO mode. The FRSRXEN bit in the UCPDCR register controls the FRS detection in the sync node. When this bit is set, the FRS detection is enabled. The digital controller is in charge of USB type C level detection with debounce, fast roll swap detection, CRC generation and checking, 4B 5B encode and decode, biphased mark or BMC encode and decode, transmission and reception of ordered sets. A clock data recovery unit in the receiver recovers the transmission clock from the received bit stream. The digital controller offers a byte level interface for USB power delivery payload, generating interrupts. A DMA channel can assist the transfer of message payloads because the UCPD unit is able to request DMA transfers. The UCPD module implements two clock domains, APB register interface clocked by P clock and phi clocked by USB PD clock. USB PD clock is divided by a programmable pre-scaler to provide the CC clock, whose maximum frequency is 300 kilobits per second. Due to the biphased mark coding, two transitions may occur per transmitted bit. Therefore, the actual maximum clock frequency is 600 kilohertz. The PHY monitors the state of CC1 and CC2, either continuously or by polling, to detect and signal events to the software by setting flags in the UCPD SR register. In order to optimize power consumption, it is recommended to use polling because Type-C detectors are off between polls, rather than wake up from stop, which requires Type-C detectors permanently on. The static level on the CC pins is determined via threshold detectors in the PHY to give a voltage range value in registers, facilitating the Type-C's state machine implementation in software, and also allowing a cable orientation to be determined. The Type-C debounce subunit filters events to be reported to software. It is also in charge of ensuring the coordination between event signaling and power delivery, TX, and RX activity. The PD software stack is executed by the Cortex M0 plus core in the STM32G0. It is based on messages and events. Events are reported to the Cortex M0 plus core through interrupts. Regarding messages, only the payload is under software control. The digital controller performs message encapsulation with preamble, start of packet, CRC, and end of packet. The software stack includes the protocol layer, the policy engine, the device policy manager, and the system policy manager. The system policy manager may control several PD ports in order to implement platform level power management. Three software layers are defined in the PD specification. Layer one is device policy manager or DPM. It is in charge of device level system management and monitoring. It determines the power plan and contracts depending on current power state. Layer two is policy engine or PE. It controls a single UCPD port. Message sequences are defined to request power resources, performing source or sync transitions. This layer implements power negotiation, swapping, and handles message flow errors and reset. Layer three is protocol layer or PL. It is in charge of constructing and deconstructing PD messages. This layer automatically returns good CRC when a message is correctly received and also handles transmission errors, such as timeout and retries. In addition to transporting data digits converted into 5-bit codes, the PD protocol also transports signaling patterns called ordered sets. They are composed of four 5-bit K codes and are tolerant to transmission errors through a redundancy mechanism. Ordered sets, such as start-of-packet or SOP, are necessarily present in packets. The digital controller automatically inserts them in the transmitter and strips them in the receiver after having checked their validity. The ordered sets defined in the PD specification are used to signal a cable or hard reset condition and delimit the beginning of packets. The PHY automatically inserts the preamble, the start-of-packet or SOP, the CRC, and the end-of-packet or EOP. The receiver PHY handles these fields and removes them. The header field and possibly the payload fields are entirely handled by software. The PHY does not interpret their contents. The preamble is not encoded. It is used by the receiver PHY to receive clock data. All the subsequent fields are encoded in the transmitter and decoded in the receiver. The Type-C connector does not support a dedicated reset signal. Consequently, reset conditions are signaled by using specific PD packets transferred over the CC line. Two types of reset are defined. Hard reset, which aborts the ongoing transfers, and the cable reset, which does not require a high priority treatment. The sequence required to issue the reset packet is described in this slide. The PD specification describes built-in self-test or BIST packets used to test whether the CC line is functional. Bists are sent on a software decision based on fields in the UC PD-CR register. Software can enforce the transmission of a BIST packet and can also configure the receiver in test mode. Received BIST packets are not submitted to software, however their CRC is checked. Two formats of BIST packets are defined in the PD specification. BIST test data, which is a packet containing a payload used to test the digital controller. BIST carrier mode, which is a single pattern infinite length mesh used to test the CC in an oscilloscope, for example. The Type-C state machine is implemented in software. The Type-C state machine depends not only on CC pin levels, but also on the port roll. In sync mode, it depends on the Vbus presence detection. In source mode, it depends on the Vcon generation and the Vbus state, on, off, voltage level, and discharge. The UC PD module only controls the CC lines. Other modules are involved to control the Vbus and Vcon power supplies. In source mode, GPIOs are required to control the power delivery dynamically. In sync mode, ADC channels are used to monitor Vbus and Vcon supplies. The UC PD can be programmed to remain active in stop 0 and stop 1 modes. The detection of a PD event, while the MCU is in stop mode, causes a wake-up condition, signaled to the EXTI unit, and then to the PWR unit. The following events can be configured to cause a wake-up request. Events on the BMC receiver, such as message receipt, fast roll swap request, events on the Type-C detector, such as attachment and detachment. The UC PD is able to wake up the MCU from stop mode, if enabled by setting the WU PEN bit in the UC PD CFG2 register, when it recognizes one of the relevant events listed below. Type-C event, relating to a change in the voltage range seen on either of the CC pins, visible in Type-C B-State CCX, or Power Delivery Receive Message, with an ordered set matching those filtered, according to 8 to 0 of RxOrdSetEN, visible by reading RxOrdSet. At UC PD level, three types of events requiring kernel clock activity may occur during stop mode. Type-C BMC RX and FRS detection. In order to function correctly with the RCC, the clock request signal is activated if WU PEN bit is set when the following events are detected. Activity on the analog 5-voltage threshold detectors, which could later be confirmed to be a stable change between voltage ranges defined in the Type-C specification. Activity on power delivery, BMC receiver, coming from the selected CC pin, which could potentially generate an Rx message event later, that is, RxOrdSet. Activity on power delivery, FRS detector, which could potentially generate an FRS signaling detection event later, that is, FRSEVT. Type-C voltage threshold detectors coming from either CC pin. The power delivery receiver signal coming from the selected CC pin. The FRS detection signal coming from the selected CC pin. When an interrupt from the UC PD is received, then the software has to determine the source of the interrupt by reading the UC PD SR register. Depending on which bit is set to 1, the interrupt service routine should handle that condition and clear the bit by writing to the appropriate bit in the UC PD-ICR register. This slide summarizes all the events detected by the UC PD module that can cause interrupt requests. Please refer to the training linked to this peripheral for more information. STM32G0 DMA controller. Reset and clock controller. Extended interrupts and events controller. System configuration controller. Power controller.