And to compare them, I'm going to show a few different examples. So with switching is a way to deliver data through a network via our intermediate nodes where those intermediate nodes are switches or switching nodes. And the different ways in which we can set up that path and deliver the data across the path, across the set of switching nodes. And we mentioned on Monday we had circuit switching and packet switching and circuit switching based on, well, developed for telephone network. So it's been around for a long time where we set up a connection and that gives us a path all the way from source to destination. And once we set up a circuit, this connection, we can send our signal along there and the intermediate switching nodes are configured such that the signal effectively passes straight through. So the end result is that with circuit switching, it's like having one long link from source through to destination. There's some complexities of multiplexing and so on but that's the end result from the user with circuit switching. Circuit switching works well with a constant amount of data being sent over some period of time because we reserve resources. If you reserve the resources, that is the capacity of the links, the capabilities of the devices, of the switching nodes, means you're guaranteed to be able to use that capacity when you want to send your data. That's good for your data transfer but it can be bad in terms of efficiency of the network because you reserve 10 megabits per second but if you only use 1 megabit per second, 1 out of 10, then with circuit switching no one else can use that remaining 9, that spare capacity. So if you reserve a certain amount in circuit switching but don't use that, then the rest is wasted. That's the problem with circuit switching. And packet switching tries to overcome that by allowing the unused capacity to be used by others and we do that by breaking the data into packets. One, so in packet switching we had two types. We had datagram packet switching and virtual circuit packet switching. Coming back to this idea of reservations, an analogy that people use is to talk about road networks like the roads which we drive on. And circuit switching, consider the case where you have some VIPs travelling from one location to another. So for example, a member of a royal family, some high-ranking politician, what do they do when they need to drive somewhere? They close down the road with which those people are going to travel on. So we have public roads, but when some VIP needs to travel somewhere, then what often happens, and we've all seen it, I think that in advance, the police will close down the intersections so that cars can't join that road where the VIPs are going to travel on. And when the VIPs come, then they just travel straight through the intersections along the road at whichever speed that they're going, 120 kilometres an hour or whatever, whatever the road enables. So that's maybe we can equate to circuit switching. What happens to get the people from A to B, from source to destination, think of the intersections as the switching nodes. They allow you normally to switch the data into different directions. So what happens is that in advance, we configure the intersections so that the data that we're going to send is going to go straight through those intersections. We reserve the road for that specific data transfer for those people. So the road is reserved for that transfer of people. What it means is, so we set up that connection and when we're waiting for people, the VIPs to travel along that road, no one else can use the road. And you may have to sit and wait at an intersection while someone else has, well, the VIPs are travelling through. So no one else can use the road, which is good for those people who are, the VIPs who are travelling, because they can go from A to B with no stops at the intersections, no delay at the switching nodes, and transferred at the full data rate. It's bad for the people who have to wait at the intersections while that road is closed down. So reserving the resources is good for the data transfer, the quality of that data transfer, but bad from other people's perspective who cannot use the road when it's unused because it's been reserved. So that's a case of circuit switching. Maybe a case of datagram packet switching would be just you and I need to go from A to B, or a group of people, say all the students from SIT need to drive into the city. We just get in our own cars and we drive following our own path. Someone may take a different path than I take. So our packets, our cars, can go in all directions from the same source to the same destination. And of course when we get to intersections there may be some delay, because other cars are going in other directions. So that delay slows down our total time to get from A to B. So with packet switching we send our packets separately representing the data and at the switching nodes they must be processed, causing some delay. What advantage do we get with packet switching compared to circuit switching? So what's good with packet switching? We've got a bad thing in terms of we now need to send our data in separate packets. What benefit can we get? It can be more efficient, especially when the, again, the amount of data needs to be sent varies over time. With circuit switching we reserve the path, no one else can use it while it's reserved. With packet switching, we don't necessarily reserve the path, we send our packets and what happens is if some people are sending lots of packets, where others are sending a few packets, then if the network is built correctly then in most cases all of those packets can still be delivered across the path. And at another time when someone's sending very little and another person needs to send a lot, then again by sending individual packets that switching nodes can combine or consider all incoming packets and utilize the output link by sending everyone's packets across that same output link. And that's hard to explain. I've got another example to try and illustrate that. You don't have this, but just follow along. Here's a simple network. The squares are our stations and the circles are our switching nodes, a simple network. And for the main part we'll focus on the top one sending to the bottom one, the source and destination. Let's consider circuit switching first. What happens? So let's just focus on this path, we've chosen this path. In circuit switching we need to first establish the circuit, set up the path. We send some special message, a short message to the first switching node. When it receives that it configures the switch in preparation that this circuit is going to be established. So there's something done at the switch saying that there's potentially going to be a path from source through to destination to the switch. And forwards this sometimes called a request message, a call request message, connection request message to the next switch which says okay there's likely to be a connection from A through to B. And then when the destination receives it if everything's okay it sends back a response. It accepts this request and sends back a response. Sends back a short response saying I accept this connection and as that passes through these switches these switches confirm that we are going to have a connection or a circuit from this source to this destination. And they set themselves up and we saw in one of those early pictures in the operator of the telephone exchange they connect this input or this line into this line inside the switch. Of course there's complexities of doing that but conceptually we connect those lines together and the response comes back and same at this intermediate, at this switching node it configures to connect this line to this line. This is just the connection setup. Now we have a connection. This is circuit switching. Now we want to send the data. So the source starts sending data and in the concept of packets we just transmit the data that we have. In fact usually we think about it as a signal. We take our data and we send a signal out of here and that signal passes all the way through the switching node to the destination. So we start transmitting some data it comes out of the computer and it keeps coming out and think of that data in circuit switching simply passes through the switching nodes because all the switching node does because it's already configured anything coming in here is configured to go directly out here and simply passes that data through onto the output link and it passes through the network through those intermediate links the switching nodes and is received at the destination. In fact once we've set up the circuit with circuit switching remove these switching nodes and consider this as just one long link. If you want to look at the total delay to deliver that data well it depends upon the distance and the speed at which we can send the data so transmission and propagation delay there's very little usually we assume zero processing delay inside the switches because the signal just comes in and goes directly out so it's as if the switches are not there once we've set up a circuit. The problem with this is that although I have it coming back to our network we just looked from the top one sending to the bottom one then maybe other stations wanted to send across this network at the same time the problem with circuit switching as we said is that we reserve the capacity even if we've set up a connection and A or the source is not sending data to the destination at this point in time no one else can use the resources reserved for that connection so it's inefficient from that perspective. Let's look at packet switching and I'll use virtual circuit packet switching as an example same network but let's consider packet switching in virtual circuit packet switching we simply use packets now and try to behave like circuit switching so same source and destination we still set up a path a virtual circuit by sending a request saying I want to connect to this destination similar to before except this request message is processed here and it stores some information that in advance it's possibly going to be a virtual circuit from source to destination we accept that request send back a response and in fact the packet switches store in memory some information saying from now on anything coming from this source to this destination if I receive a packet with a source address of this one and the destination address of this one when I receive a packet I will send it for this switches perspective send it on this link so they store some information to tell them the source address, destination address and where to send it next so we set up a path or a virtual circuit and then we start transferring data and now we break that data into packets so we think the data that the source has to send we break into three packets just to keep it simple and they have many more and we send those packets one at a time there may be some delay between sending the first packet and sending the second packet depends when we have the data available that is if the application generates some data to be sent then that's the first packet and then a few milliseconds later has some more data to send maybe that's the second packet so I'm trying to show that there may be some time between sending those packets they are sent from the source to the switching node and the switching node receives a packet it must process that packet and at least what it must do is look at the header I haven't drawn the header but there's a header for this packet inside the header should be the source address and destination address so what this switching node does in packet switching is looks at the header sees that the destination is here and compares to what it stored previously when we set up that connection and determines ok the destination is here it's coming from this source I know I must send that in this direction not out here, not out here so processes which take some time with circuit switching the processing of the data is almost zero it's very fast of course the time to process the data depends upon the packet depends upon what's in the packet but also not shown here there may be packets coming from other directions at the same time there may be packets coming into this switch from this direction, from this direction so in fact the time to process that blue packet that arrives depends not only on that packet but on what others are sending so there may be a large delay there and then we send it out and we just send those packets through the network and because of the varying delay in the switching nodes this one there may be some increased delay or time between the first and the second packet now so we transmit the first packet a little bit later we send the second packet across the link and in fact you can think across this link that we're inefficient all the time we're transmitting the first packet and then there's some delay before we send the second packet we'd like to be sending packets all the time across the link and then we deliver them eventually to the destination let's consider now in our network we have another virtual circuit setup from this source to this destination this red one, it's been set up already I won't go through the setup process and the source the red one wants to send two packets through the destination in the same way with packet switching it generates the packets, transmits them and at a similar time our blue source starts transmitting its packets and they arrive they start to arrive at this first switching node at the same time the red ones and the blue ones come into the switching node on two different links so the switching node looks at the headers who is the source, who is the destination and determines in fact in this case it needs to send them all out on this link and in fact the benefits of packet switching arise now in that even if there's a small amount of data coming from one we can combine what we send out on this link we can combine the packets from both the sources so we can transmit let's say the first packet from the blue one then the red packet then a blue packet and so on so from this output link we're actually transmitting packets all the time or very close to there's a small gap here that's more efficient utilization of that link because when I just had the blue one transmitting we saw there were some gaps here when we transmitted across this link but if there's someone else who also wanted to send packets then if we're lucky what can happen is that we can get to transmit all those packets one after another across this output link fully utilizing the link that's good if I have some link I want to be sending across it all the time because if I'm not that's inefficient so it works out in most cases with packet switching because sources have different amounts to send in some instant the blue source has a lot of packets to send the red one has a little a few packets and then maybe a second later the blue one has just a few packets to send the red one has many packets to send then they send those packets and if they need to traverse the same link then if our network is built well and designed well then usually we can be sending packets all the time across this link sometimes we're sending a lot of the blue packets and a few red ones other times we're sending a lot of the red packets and a few blue ones but again fully utilizing that link or increasing the utilization increasing the efficiency the second switching node simply receives a packet looks at the header determines where to send it the red ones it knows need to go in this direction the blue ones in this direction and they're delivered to the destination so this is an example of virtual circuit packet switching the same concept supply with datagram packet switching except we don't set up a connection in advance but we still have an advantage of by using packets smaller chunks of data then when users are sending a lot and some other users are sending very little we can combine their data and efficiently utilize the links and overall efficiently utilize the entire network with circuit switching if a user reserves a connection but sends very little then what they're not using is wasted and that's inefficient and that's really the summary of those three switching techniques I don't show datagram packet switching here it's the same as the blue and red one except we don't have a path set up in advance maybe the packets take different paths it's possible with datagram packet switching any questions on these three switching techniques let's go back to our lectures let's compare the three from the perspective of how long it takes to transfer the data circuit switching on the left virtual circuit packet switching in the middle datagram packet switching on the right and it's showing that the total delay or the total time to transfer data in the first two cases we need to set up a connection there's slightly different ways in which that's performed but the basic approach is that we send a request a short request message from source to destination which responds with some in this case a call accept or a connection accept request a message and similar with virtual circuit packet switching we send some call request packet and responds with a call accept packet saying we accept we're prepared to receive the data whereas with datagram packet switching we don't do this connection setup we just send the data immediately there's no delay of setting up this connection at the start with datagram packet switching for the data transfer with data with circuit switching we don't have packets we just transmit the data and we can think the data just goes through each switch until it's received by the destination so there's no delay inside the switches or very very small delay so you can think that we have one piece of data we transmit it this is the transmission delay there's some propagation delay the propagation delay of the path is really the propagation or the sum of the propagation delay of each of the links if it takes 10 milliseconds to propagate from the cross each link then it takes 30 milliseconds to propagate across the path but when we use packet switching we transmit a packet one at a time and the switching node will not transmit on the output link until it's fully received that packet and processed it by looking at the header it's received a packet it's received at this point there may be some small processing delay then we transmit packet one on the second link it's received and transmitted across the third link and similar with packets 2 and 3 and we see that with virtual circuit packet switching and datagram packet switching the data transfer phase is the same there's no difference which one's fastest it's time to transfer our data in this case we see datagram packet switching is fastest is it always alright it depends, good compare these two compare datagram packet switching with virtual circuit packet switching under the same conditions datagram packet switching is always faster because the only difference is that assuming we have the same amount of data and the same size packets this time is the same as this time but with virtual circuit packet switching we have an additional time to set up the connection so my computer wants to send data with virtual circuit packet switching at time zero I want to send data what happens first is I send a request get back a response and then send the data so there's this extra delay of setting up the virtual circuit always with virtual circuit packet switching now so datagram packet switching has a smaller delay than virtual circuit packet switching what about then circuit switching versus datagram packet switching which one takes less time what does it depend upon okay good it depends upon the size of the data and roughly under the same conditions well what's the delay for datagram packet switching time to transmit data but also we have this delay of headers inside the packets we have to transmit them and we have this delay that we cannot transmit the first packet until we've fully received it so there's some delay there delay inside the switching nodes which is not present in the data transfer for circuit switching in circuit switching no header just send the data all the way through so the data transfer phase of circuit switching will be faster than that with the packet switching techniques but circuit switching has this additional delay at the start of setting up the connection so which one is faster well it will depend upon how much data we need to transfer if you can imagine that the data we have a lot of data to transfer that is if I drew this again the data to transfer went all the way down there then the time to set up the connection is just a small percentage of the total time whereas with packet switching if we have many many packets to send there's a lot of overhead of headers so circuit switching the total time can be less in that case depending on the amount of data normally if we have a lot of data to send setting up a connection is not so much of a problem but if you only have a small amount of data to send then setting up a connection is a waste of time that's the general trade off in the internet most of our applications today we often send think of web browsing and then receive a response we may access the same web server again or we may access other web servers so it generally doesn't make sense to set up a connection just to transfer say a single packet to a server get a single response back and then close that connection because the overhead of setting up the connection is quite significant and in fact in the internet datagram packet switching is used and in most networks there are some cases where virtual circuit packet switching is used in wide area networks but in general for the internet especially from the perspective of the internet protocol which we'll cover datagram packet switching is the technique chosen this compares the three switching techniques some of them we haven't discussed and we will not, you can read through let's just highlight some of the main concepts between the three circuit switching we set up a dedicated transmission path that is we set up a circuit from source to destination and it's reserved for that data transfer there's a path that is there's a physical connection from source through to destination it's not the case with packet switching even in virtual circuit packet switching although we set up a virtual circuit we're processing packets one at a time we don't have a physical path from source to destination reserved packet switching transmission of packets which routing will return to later so we talked about routing with the delay circuit switching and virtual circuit packet switching have some set up delay call set up delay there's small transmission delay almost zero with at their switching nodes circuit switching but with this packet switching techniques we have this delay of transmitting a packet that's larger than for circuit switching what happens if things go wrong if in circuit switching we try to connect to a destination and that destination is busy then we may get some response back saying the destination is busy we don't have that concept in datagram packet switching in data it may not be delivered we may get some notification our data wasn't delivered and similar to circuit switching virtual circuit packet switching we may try and connect it's possible that the destination says no I cannot set up a connection deny the connection importantly what happens when we have a lot of data a lot of information to send across the network with circuit switching yesterday if our resources are reserved and someone else wants to make a phone call that phone call is blocked it's not set up so we have the concept of call blocking in circuit switching it may be the same in virtual circuit packet switching we if we have some measure of resources we try to set up a new connection then we may have to block that connection but importantly in circuit packet switching as more people send data what normally happens is that inside our switches as more people are sending data there's a larger delay inside these switching nodes because if the blue one is sending data in and everyone else is also sending data into this switching node the switching node can only process one packet at a time others will have to wait or queue they'll have to wait in a queue for the first packet to be sent so the delay at the switching nodes increases as the amount of data needed to be sent increases in packet switching the queuing delay increases something about the size of the nodes not so important for us this one, the second or last one is key in circuit switching the word used here, bandwidth but fixed resources allocated for the data transfer with packet switching we dynamically use those resources, the bandwidth the capacity fixed is good from the perspective of the people who want to send data they get guaranteed performance but it's bad in terms of network efficiency when those people vary the amount of data they want to send that's why dynamic use of the resources is better for efficiency and that's all I want to cover on switching the way to get data across a network from source to destination the one thing that we skipped when we talked about networks is we said that we send data across some path across a set of links we often have multiple different paths to choose from how do we choose which path to use and that's our next topic routing how do you choose the path to take from the source to the destination I want to drive from here into the centre of Bangkok go shopping at Paragon what path do I take I'm sure many of you have driven into some places in Bangkok which path do you take how do you drive into Bangkok or your friends expressway, why it's the fastest way if we have so one way to choose the path to take there are many paths of course to drive into say Paragon then there are many different roads we could take many different paths we could take so how do we choose which one to take the next area we could use is well in some cases there are expressways or highways which you can use or toll roads let's use them because they don't have so many intersections and in general the cars can travel faster I'm a cheap person I don't want to spend money on a toll road what else can I do we're driving let's say we're driving I'm cheap I've got no money don't go up go under the tollway in some parts there's a road but that road is not always present from here into Paragon then sometimes we have to take some side roads how do I choose which ones to take then why not here we are at SIT and here's Bangkok why not drive up and out to the east and come down there how do I choose the path to take shortest path shortest path in what measured in what one way to measure one way the shortest distance I've got a map I've got google maps here accurate what I can do is get a ruler and measure what's the actual distance from A through to B and scale that up to kilometres and then we'll look at individual sections of roads as we come up to an intersection we may have to turn and work out what's the distance if I take this path 40 kilometres if I take a different path it's 45 kilometres choose the path with the least distance there's one way why not why not traffic sometimes at some of the intersections there's a lot of traffic that is there's cars coming from on your direction from the opposite direction and from the side directions which means that that intersection I must stop at the stop lights and wait for three minutes so the more traffic on that path the longer delay I'm going to have there may be another way to choose a path would be to select a path which has no traffic or very little traffic the least traffic let's have a look at these are some of the results that google maps returned this morning the first path it showed me here here it says the distance 31.4 kilometres so let's say that's the distance of each of the segments the traffic is blue line the normal time 30 minutes so google has done some calculation if we travel at normal speed across each of those road segments the time it would typically take is 30 minutes but it gives me a bit more information in current traffic this was 8am this morning it says 46 minutes google is a little bit smarter the time to be the same it has some information about the current traffic conditions so and then it actually has three options of paths the second option distance of 32.6 kilometres typical time 36 minutes current 1 hour 5 minutes a different path and then this one 39.5 kilometres further larger distance 56 minutes current time less than the second one if we consider the traffic and a fourth one I select the option here avoid the tolls I don't have the money it gives me some options and here was one distance 35 kilometres current time 58 normal time 41 minutes in in our road network we need ways to choose the path to take to get from A to B in our computer network our communications network we also need ways to choose the path to take from source station to destination station via those switching nodes which links do we go via the general process is called routing we need to choose a route or choose a path so we have algorithms to choose the best route and when I say best well there are different criteria for measuring best and we've just mentioned some of them the distance in terms of kilometres well same can be applied for communications network choose a route for my data to go from here through to the US well maybe there's path that go up via Tokyo there's one to Singapore and through south east Asia across the Pacific there's a path that goes via Europe choose the path which has the least distance there's one criteria for choosing a path through a network coming back to our road network Google has calculated some typical times okay 31 kilometres going back to our first one 31.4 kilometres 30 minutes typical time but in current traffic 46 minutes if I go back the map now so this was at 8am look at it now it's 9.30am 10am the distance is it going to be the same yes the distance doesn't change for this path the typical time will probably be the same because I think that's the time that is calculated based upon the distance and the road speeds in current traffic time most likely will be different okay because now past 9am maybe there's less traffic on the roads and they calculate it to be say 40 minutes not 46 minutes choosing the best path of course we have different criteria for choosing the best path like distance amount of traffic cost do we avoid the toll or not but another thing that's important is in some cases the information that we use to choose the best path how up to date it is okay so in this case the 30 minutes time is probably a time that is typical with very little traffic but Google is getting responses how do they get it well maybe they get it from traffic reporting stations from the city traffic cameras get some information about where the congestion is and that feeds back in and then updates the current traffic time I don't know how often it updates maybe every 30 minutes every 1 hour it may depend upon where the information comes from yeah okay from from users information from users and where they are so there's different sources for where that information may come from the rate at which we get updates is choosing the best path because if we update this in current traffic every 1 minute it's an accurate representation of the current traffic there's a traffic jam 5 minutes ago at 1 intersection which increases this from 46 minutes up to 50 minutes then that may allow me to choose a better path so the more frequently we get updates of what's happening in the network the more more chance I can choose the best path if this in current traffic updated once per day it wouldn't be very useful because during a day during that 24 hours the traffic varies a lot the congestion varies in different locations so the frequency of the updates is very important and look the source of those updates where did the information come from did it come from different points in the network and what cost was involved of collecting that information is important we said we may want to choose a path which has low cost, low financial cost another criteria so that's an example for road networks the same applies with communication networks and that's our topic on routing how do we choose a route through a switched communication network and from now on we're going to focus on packet based networks, packet switching but the same similar concepts for routing also apply for circuit switching but the examples we'll use will be for packet switching here's our network from before so to get from A through to D which path or route do we take so we use the word path or route to mean the same thing that's the problem that we're trying to solve what's the best path from A through to D well the answer, choose the best path ok well then we need to define what do we mean by best what criteria do we have to define best of course we want the best path but what do we mean by that so what do we mean by best how to choose that note that in our example with 6 stations with 7 switching nodes there are several paths here there are not many to choose from not a difficult problem to choose the best path in this case but in a real network across a country between countries even within cities the number of devices, stations switching nodes links it can be very high so the connectivity is much more complex in the examples and in fact you cannot easily just look at the picture of the network and choose the best path you need some algorithms to calculate it for us so what do we mean by best and how do we choose the best path once we define best what algorithms do we have available when there are many possible paths choose the best one we're going to focus on routing packet switch networks but it's the same essentially in circuit or packet switch networks so coming back we'll see that we need to define what is best and we need some algorithm to choose the best path a routing algorithm some general requirements of some routing algorithm needs to be correct so a routing algorithm takes as an input the source and the destination and returns as an output the best path between source and destination so if the source is A destination is B a routing algorithm must return a path between A and B it cannot return a path from A to C that would be incorrect that's almost obvious we don't want a routing algorithm that doesn't get us to the destination it should be simple because we'll see that we need to implement this routing algorithm in different nodes it must do some processing simplicity is a way towards getting things which are easy when we implement and cheap the algorithm needs to choose a path from source to destination some other requirements should be robust that is the example of robustness is that we choose a path from A to B and then we notice the network there are some errors or there are problems in the network then we should be able to adapt and choose a better path if it becomes available so do some adaptation as the network operates so even when things are not working well when we have errors it should still work stability is almost a conflicting requirement with robustness stability says that we don't want to switch between paths too frequently I have a path from A to B and I'm using that path to send my data and then another path becomes available which is slightly better than the current one and we switch to use that other path and start sending the data there but then the previous path becomes better again because the network conditions are changing so I switch back to that previous path and I keep switching between paths and sending my data sometimes on this path sometimes on another path that can become a problem because our data can start to be reordered and we have different delays on each path we can say we get an unstable path we keep changing paths we want to select the best path but we don't want to switch between paths too often and it depends upon our requirements of our applications as what is too often stability don't change paths too often in fairness change paths when needed to overcome errors or problems we need some trade off between those two choose optimal paths ok we've said that choose the best path efficiency we'll come back to fairness efficiency the process of choosing a path will see requires exchanging some information across the network in the process of the process of Google Maps selecting these three best paths what did it need to know it needed to know the map of the streets it needed to know information about the the speeds along each of the roads that you can travel on and importantly it needed to know something about the current traffic conditions so it could give an estimate of at this point in time how long will it take now to collect information about the current traffic conditions there's some overhead because somehow we need to collect that information we want to minimise that overhead in collecting information but still we want to have up to date information so efficiency is about when we collect all the information to determine our path we want to minimise the amount of processing we do when we collect that information and also minimise the amount of overhead that we transmit across our network but still choose the best path so there are again some trade-offs here we cannot just say don't collect any information because it may mean we don't choose the best path fairness is a hard one to to given an example it may turn out in some cases with routing algorithms that some stations can get better paths than others which means if station A to D always gets the routing algorithm always chooses a better path than what station C to F gets then it's unfair for one pair of source destination so there can be extreme cases of that where a routing algorithm gives us is efficient, robust and stable but it may mean that for some sources their data always goes across very long paths and takes a long time but for others it takes a short time across very good paths so we want to avoid that and try and treat all stations the same and be fair amongst them I think we'll see examples of optimal paths efficiency especially and these two as we go through we will not see an example of fairness so we want some algorithm that will choose a path from A to B which meets these requirements let's introduce some terminology so we can give some examples we have links between nodes so now we talk about nodes, switching nodes simply nodes we have a link between them a direct connection between them actually let's explain them on this example here are six switching nodes there may be stations attached to them but let's say we have a network of six switching nodes N1 through to N6 we have links between those switching nodes so there's a link from N1 to N4 there's also a link from N4 to N1 often we have links in both directions a link is a direct connection between two nodes a path or a route is a connection between two nodes which may have one or more links so a path give me a path from N1 to N4 a path from N1 N4 is direct any others N1 to N4 give me one example there are many others N1, N2, N4 that's a path usually we define a path by the set of nodes we traverse there are multiple paths from N1 to N4 N2, N1, N2, N4 N1, N4 N1, N3, N4 so they are paths they may contain one or more links to traverse one link is to make one hop we often measure hops talk about hops this is one hop to go from N1 to N6 on the path 1, 4, 5, 6 there are three hops we often talk about hops we traverse along that path what we've got next a neighbor a neighbor of a node is the node which are the other nodes which this node has direct connections to that has links to N1 has three neighbors the neighbors of N1 N2, N3 and N4 because N1 has links to those three nodes so we have neighbors and for each link we assign some cost and they are the numbers shown on these arrows so the arrows are the links the numbers are the costs of those links the costs of sending data across that link now here cost does not mean financial cost it's a general cost we have to define what it means so when we say the cost to send from N1 to N4 is 1 and to send from N1 to N2 is 2 well it doesn't mean 1 bar, 2 bar it may mean a financial cost but in general it may mean to do with many different metrics delay throughput we'll see more metrics as we go through so we assign some general cost to the links the cost may be different in each direction it's possible so it costs 1 unit to send to N4 but for N4 back to 7 it costs 7 units so it's possible and a topology when we talk about a network topology it's the arrangement of those nodes and links this is one network topology if I removed this link here that would be a different network topology if I added another node and some links that's a different network topology with the arrangement of links and nodes what our routing algorithm should do is or what we generally do in routing is find the least cost path from source to destination from N1 to N6 the least cost of a path is the sum of the cost of the links on that path so that's what we define so each link has a cost the cost of a path is the sum of the cost of the links along that path what's the least cost path from N1 to N4 there are multiple paths give me one least cost path this is an easy one the direct link from N1 to 4 the link cost is 1 the path cost is 1 if we went N2 and N4 the path cost would be 2 plus 2 would be 4 we want to choose the path with the least cost in some cases from N1 to N6 least cost path N1, N4, N5, N6 has a cost of 1 plus 1 plus 2 is 4 from N6 to N1 maybe are you sure you actually need to check all the paths it's not obvious I think from from N6 to N4 if we went N6 to N1 6541 has a cost of 4 plus 1 plus 7 is 12 another path 6 to 5 to 4 to 2 to 1 has a cost of 4 plus 1 plus 2 which is 7 plus 3 is 10 any lower cost path than 10 6 to 5 to 3 5 then to N1 is 13 it's not obvious to choose the least cost path here even with such a simple network one of the smallest networks you'll see you cannot just look at it and choose the least cost path imagine the network now has 100 nodes thousands of links many possible paths so we need some algorithm to calculate the least cost path what is an algorithm that you know you've done it before most of you have I know you remember maybe Dr. Booneerit may have taught or someone else in 1st or 2nd year Dijkstra's algorithm so there are different algorithms that given this information follow some steps and we'll always find the least cost path Dijkstra's algorithm is one Bellman Ford is another algorithm so there are different algorithms to take the network topology and we'll return the least cost path we're not going to cover those algorithms most of you have covered them before in earlier courses but we'll accept that there are some algorithm that can do it for us we don't have to manually do it we can calculate a computer can compute it so our aim given some topology choose a route choose a path with the least cost that's easy if we have this topology then we apply some algorithm and it returns the answer let's come back to some things what performance criteria do we use to select the path where do those numbers of the costs come from so there are different ways to select there are different sources of those numbers the number could mean a financial cost it could mean something related to delay something throughput and in fact can be other things like associated some cost to do with the security of using that path so there are different performance criteria that we can use when is a path selected that is I have some data I have a packet to send do I select a path for every packet that I want to send or do I select a path every year so there are different choices there and they have some impacts on performance which nodes are responsible responsible for selecting the path which nodes select the path is it the source node that chooses a path all the way through the destination or maybe all nodes are involved in choosing the path from source to destination or maybe there is one central node some special server there are again different options which nodes provide information about the network status so if these costs these numbers here are to do with the current delay across a link or a portion of the network they may change over time the delay may vary over time it may depend upon the delay at nodes even so the delay of a link we may count processing, transmission propagation and even queuing delay so if the the cost varies over time then we should to choose the best path get some update about the current value well which nodes provide that updated information which nodes provide information about the current costs and the usage of the network even the topology the topology may change today I have six nodes tomorrow there is a new node added to the network so we need to get that information about the new topology so that we can calculate the best path and how often do we get that information that's important so we need to answer these questions in different ways for addressing these questions and this slide gives some answers to some of those questions and we will discuss them to finish today performance criteria how do we what does this number 1, 7 and so on what do these costs represent well they can represent different things number of hops so a simple cost metric that we can use number of hops so in fact if we use number of hops each link would have a cost of 1 on our diagram all links are cost of 1 and then we choose a path with the least number of hops that's a very simple way and commonly used in some networks another criteria may be financial cost choose the path which is going to be cheapest for us to send our data because there is a financial cost of sending data across links especially if you're connecting across multiple different a multiple if you're connecting across networks operated by different companies so there may be some cost of using their network so consider that when you choose the path delay is another common one choose the or assign cost to links which represents the delay of sending our data across that thing because in many applications to send data from source to destination we care about minimizing the delay choose the path which gives us the shortest time to transfer or to send a single message from A to B so the delay of the link to do with transmission propagation, queuing and processing delay is commonly used another one may be throughput I care about transferring a lot of data across the link across the path from source A to destination B then if we can assign costs which are related to the throughput choose a path which gives us the highest throughput so there are examples of some performance criteria that we use to assign cost to links we need some way to get a number a cost to a link once we've got that we can assign cost path there are others one may be security may be political factors consider routing through throughout the world you have a company in two different countries and it's the laws of those one of the countries you're operating in so you cannot send confidential data via some third country because of political factors so in that case you could potentially choose a route that bypasses a country bypasses some region because you don't consider that region to be secure you don't trust it for example so there are other factors that can be used here but these are the common ones when is a path selected well commonly if we're using datagram packet switching per packet is one option but in fact the path may not change across multiple packets so when we want to send an individual packet we use some information to determine who to send it to if we're using virtual circuit packet switching per session or whenever we set up the connection then the process of setting up the connection we choose a path and then all of our packets belonging to that session or connection follow that same path so these are some examples of when do we choose where we want to send a packet or packets belonging to an entire session which nodes are responsible for selecting the path so the decision place all three basic approaches each node plays a role so some distributed approach where all nodes have a say which path is used back to our example if N1 has some information so one approach could be let's simply send if we have calculated least cost paths then N1 knows the least cost path to N6 is via 4 then what N1 does is sends the packets to 4 N4 knows the destination is 6 and if N4 knows that the least cost path to 6 is to 5 then it sends to 5 so each node is having a role in choosing where to send the packet and each node needs to collect information to find out what is the least cost path so a distributed approach where all nodes have a role another approach could be a centralized approach where this one special computer may be not shown here some central server that calculates least cost paths and is used whenever we want to send data maybe that's suitable in small networks what was the other one source originating node the source node chooses the path and an example may be the source chooses the best path N1456 and it sends a packet and inside that packet it includes the path information so in the header it says this packet must traverse 45 and go to 6 so it sends it to 4 4 all it does is reads the packet and follows the packet instructions which says send to 5 so that's an example of the path is chosen by the source and the other nodes along the way just follow the information of the path that was chosen by the source the source routing is possible let's briefly mention the last two and then we'll finish and let's give a couple of examples where does the information about the network come from? assuming the costs may change over time so at this point in time the costs are this 5 minutes later the costs and the links may have changed in that case to choose the best path we need to collect that information about the updated costs so where does that information come from? where does the updates come from? well the worst case is don't collect any information or don't collect any information local means we don't have any source of information the best case would be all nodes any updates at each node is made available to every other node and all links but there are some intermediate cases for example use just local information local for example the information local to N1 N1 should know about its links N1 doesn't know about the links to node 6 but the links connected directly to N1 and the costs of those links would say is local to N1 so if this link changes from cost 2 to cost 5 N1 knows about that if we consider local information if the link from 5 to 6 changes from 2 to 20 N1 doesn't know about that immediately it's not local information it would need to somehow collect or someone would need to send that information to it so if you just use local information it's quite easy because you always have access to that adjacent node that is neighbour node what we could do is that N1 knows about its links the neighbours of N1 being 2, 3 and 4 they know about their links they could send some information to N1 about their links so the link from 4 to 5 changes from 1 to 10 the cost of that link N1 doesn't immediately know about that change because it's not connected but if N4 sends a message to N1 saying my link from 4 to 5 has changed from 1 to 10 then now N1 knows about that change so if we can collect information from our neighbour nodes we can learn more about the changes in the network and the best case is to connect collect information from all nodes every node every one minute sends a special message to N1 saying these are my current links as a result N1 has an updated view of the network so there are trade-offs with each of those let's stop now what we're going to do next week we'll come back and look at these network information source network information update timing talk about the trade-offs and give a few more examples with our simple network of how these may work so we'll go through some examples what happens when the cost change how often we can update and where do we get that information from we'll continue that next week


Ben Scott of the New America Foundation, welcome to WPC TV. You've just been in a fascinating panel on big data. How do you balance the opportunities and the risks of big data? This is the $64 million question. It is like any new technology. It affords great new developments in market growth, in consumer benefits, but it also brings with it a new set of challenges. What you find is that the policy regimes that protect consumer and citizen rights are not as fast in developing as the technology is, and so each time you have a technology revolution like big data, you have a game of catch-up where policymakers seek to modernize the frameworks of law and policy to make sure that they are adequately governing these new markets. After the Edward Snowden revelations, did you sense any change in public or that case government attitudes towards big data? I think undoubtedly, and while the severity of the public outrage over this Snowden affair varies from country to country, particularly in Europe you have very serious disruptions in the transatlantic relationship and a skepticism towards the United States, towards the United Kingdom, and a skepticism towards these kinds of technologies as a result of this Snowden affair. The question is, how deep does that skepticism go? When I look at it and I see how people responded to the Arab Spring in 2011, the Twitter revolutions and the liberatory power of distributed communications networks, it is remarkable to me how quickly we have gone after this Snowden affair to people viewing these technologies as dystopian and tools of political control and social manipulation. While both images, utopian and dystopian, are monolithic and each in its own way flawed, both are now deeply felt and that arc of transition from one to the other over such a short period of time I think is something we should be watching very closely because I think it has political and economic implications. Ben Scott, thank you very much indeed. Thank you.


Good morning class, we ended the last class with almost all the inputs that is required for you to understand the second dimension that we are handling in this course namely strategy. Now, till now we have been able to cover almost all the popular strategic models and also understand some key terminologies that the corporate world use when they are handling the issue of strategy, competitive advantage and the broader issues that make them successful in this global market place. I also assured that I will be sharing a particular case study for you to better understand the finer elements and the nuances of the strategy when it comes to the implementation of a chosen model. Now, but before I do that by now you would be able to appreciate the fact that there are of course different models, but we have handled some of the most often used ones, the strategic models are namely the potter's generic strategy which concentrated on three major dimensions. One from a cost perspective that you will be a cost leader, organizations would like to be a cost leader because it finds that the value that is generated by being a cost leader is the amount of incremental profitability that the organization can make or can pass on the benefits of cost leadership to the end customer by probably giving prices that are competitive than what is available in the market. The second one was about focus where potter's view was that there needs to be a focused approach in which organizations have to build their strategic models, cannot have a multi-dimensional approach without any clarity. And the third thing is to also try to develop something that differentiates organizations from the rest. So, the third piece was the differentiation where you need to do the same things differently. So potter's generic strategy the three corner pieces of the generic strategy was cost leadership to maintain focus or to be able to produce differentiation that was the potter's view. The other view that we saw was also the CK Prahalad's view on core competency that organizations will definitely have something that is intrinsic in them that they find themselves to be very strong in that intrinsic value which he calls as the core competence of the organization. And the capacity of organizations to build on that core competency and to ensure that core competency is able to manifest in itself in different applications, business applications that could be within the industry in which the organization is operating or it could transcend across various industries. But the essence of the strategic model is that the organization is trying to build on what it considers its core competence. So that was one view of how to build a strategic model that is the CK Prahalad's view. The other view that we saw was also a blue ocean strategy which made organizations to just think out of the box to see whether they can go and charter in uncontested market space where other organizations have not tested the viability of the business option and in doing so it makes the existing competition totally irrelevant. So that was one view we saw a lot of examples on how organizations were successfully able to do this blue ocean strategic thinking where they just moved into new market spaces and in the process they made the competition irrelevant and still they were able to and they were able to build success stories out of that. Another model that we also saw was the Ansoff's grid which tried to develop a mix between market and product. Remember we were talking about existing markets new markets versus existing products new products and there were four options market penetration which had to do with using the existing product for the existing market. Remember we used this grid where we had the product the market old market old product new product new market and if you are in an existing market an existing product which means the old market and the same old product then you are just trying to penetrate the market further so that could be a market penetration strategy or you could develop the market expand the market by using the same product so you could do a market development whereby you try to get into new markets using the same product. The third alternative that was available was also product development where for existing markets you could develop new products product development and this was market development and this was market penetration and the fourth option that you had was diversification where you try to come out with new products in new markets so this was also one of the strategic models that we had in mind so broadly we were able to appreciate that there were four popularly used strategic options models and the fifth one that I call the gut feel you know some organizations some entrepreneurs feel that you know this entire conceptualization from the drawing board to the market space was just based on a gut feel but if you do a deep analysis I do not have anything against gut feel but then if you try to do a deeper analysis you will find that you will be able to somehow force fit even organizations successful organizations that were successful based on gut feel could also find themselves adopting to a strategic model which would probably fall into one of these four models that we already discussed. So it is possible to force fit even organizations that just think that it is a gut feel that makes them successful. Now having said that I just would like to present a case for today's discussion now before doing that I would like to broadly tell you the domain in which this case discussion is going to happen now the industry the broad industry domain will be the travel and tourism industry and this is where the case discussion is going to dwell around and now by travel I mean the air travel the bus the train even cabs and by tourism I would include the hospitality industry which is the hotels package tours then you have the customized tours. So this is the broad industry in which we will try to get this case started and very specifically I would be discussing our specific interest would be within this industry the inter city or the inter state bus transportation as well as the bus transport itself. Now this is going to be our focus point for the class discussion. Now before I get into the case facts we would like to understand how the bus industry the current bus transportation industry is characterized and from a timing perspective from a time frame perspective the class has to move five to six years back probably to 2005 2006 and we are going to look at the case from that time horizon. So at that point of time the year 2005 or 2006 we would like to understand how the bus transportation industry was characterized. Now let's begin with the supply side characterization of the bus transportation industry by supply side I mean the bus operators. Now how were the bus operators the bus operators who commute passengers travelers from one city to the other city from one state to the other state. We know that at that point of time it was highly fragmented you had private and government transportation it started with predominantly government transportation but slowly also the private bus transportation industry started growing a lot but it was very very highly fragmented so much to say that amongst the private if you look at the private bus operators amongst the private bus operators 65% of the bus travel were provided by bus operators whose fleet size was less than 25 and 25% of the travel was served by bus operators whose fleet size was less than 75 and the remaining 10% could be is those big ones whose fleet size was greater than 75. Now these are the ones that you currently see the big bus operators like the KPN or the Sharma transport so these are all the big ones catering to 10% of the total traveling population and of course on the other side you had the government bus transportation the government bus service and they had a different characterization predominantly low price as a result of which the service level the comfort was also not comparable to the private bus operators and they catered to a different market composition but even at that point of time there was a slow response to the competition that even the government transportation services got from these private bus operators and of course there is competition the government bus operators also looked at that competition as something from which it could learn as a result of which even the government transportation services started adopting to certain best practices though their reaction was very slow they were making some progress that is about the bus operators. Now about the process if you look at the ticket booking at that point of time the entire booking process was manual where the bus operators you know you sometimes they used to have their own office in major cities or they would have some agents in smaller cities or for a passenger we do not deal with agents or we might not even deal with the own offices we even get our own travel agents doing the tickets on our behalf and they themselves would be you know interacting with the own offices of the bus operators or through the agents themselves or in some cases the bus operators themselves will own some of the smaller city bus operators agent offices also but of course that comes under the category of agents in smaller cities and the entire booking process was manual so if you need to I will explain how the process happened but for now we need to understand that the entire bus ticketing was manual and another thing that characterized the bus travel at that point of time was the information asymmetry and I will spend more time on this because this is the key to the case discussion that because of this manual booking there was no symmetry in the information that was available from the bus operators point of view from the travelers point of view by information I meant the vacancy position the routes the price the seating arrangement and all sorts of such information that is very very critical both from the operators point of view as well as the travelers point of view and another important thing that was happening at that point of time was a major socio economic change that was happening in our country the economic change of course was driven by the amount of liberalization industry growth so we find we found that there are a lot of IT companies manufacturing companies opening up software development centers in major cities manufacturing locations in major cities and towns where it was competitive for them to start their manufacturing process as a result of which there was a migration of workforce from the rural area or the tier 3 tier 2 cities towns to some of the major cities so there was migration as a result of which it necessitated a lot of travel both for personal visiting home and getting back to work or even for official purpose where even the working people prefer to choose bus as a medium of transportation so the economic changes that happened to the landscape was also an important thing that was happening at that point of time which kind of changed the way in which transportation and more specifically the bus transportation industry was operating another thing that was also happening was a social change because of the internet penetration there was a huge explosion in terms of the communication industry communication was getting high tech as a result of which the internet penetration growth was also increasing year on year from 2000 let us say as a result of which the e-commerce as an accepted paradigm we would see we would we were able to see a growth in trade as well as personal conception on the digital space so the e-commerce industry the fundamental for which the fundamental for the e-commerce industry was the rate at which the support infrastructure namely the communication the telephone lines and the internet ecosystem was built that was also finding itself to be growing in a very progressive pace between 2001 to 2005 6 so this in effect was the characterization of the industry from the perspective of a bus operator and a traveler of course there are other changes but I am restricting only from the perspective of the bus operators and the bus travelers now with this in mind let us understand what was the challenges what were the challenges that the operators as well as the passengers faced in that existing model challenges for operators as well as passengers now to understand that we will first understand how this entire booking process happened at that point of time so let us say we had a passenger one passenger two passenger three all of them and then you had a bus operator one bus operator two bus operator three bus operator three and so on as many bus operators as there are in this industry now what linked the passengers to the bus operators was either the agent or the bus operators own branch office so you had the agent branch office agent branch office and so on now there was transaction between the passenger and the bus operator through the agent so the agent was the intermediary or the branch office of the bus operators were also the intermediary but the way in which the transaction happened was the biggest issue that was to be a great challenge for the operators and the passengers now those were the growing pains that the industry started experiencing now either it had to be through a phone or you had to manually go and visit the agent's office or the branch office and again information was retrieved from the bus operators either through phone very very remotely through manual but at times if they are very close by then even manual is possible so what happened is now suppose a particular passenger one had to purchase a ticket to reach a particular destination so he had to depend on the branch office or through agent let's assume that there was no branch office in the place in which the passenger wanted to book his ticket and it was through an agent so you had to contact a particular agent and he checks with the bus operators the routes on the availability of the ticket and this is the experience of many of the passengers and when this agent is engaged with handling a particular passenger in his office suppose more number of passengers want that particular ticket they have to necessarily wait before this agent finishes the particular passengers and finishes handling that particular passengers requirement now the challenge the major challenge was that there was an over dependence on the role of the agents because of this manual effort that is required to purchase a ticket so either they had to visit the agent's place or they could call the agent and get their ticketing done and there are so many passengers queuing up and they had to wait before each passengers each passenger finishes his particular task and suppose this agent is not able to really provide the required service and if the passenger feels that there is another agent that can help him he contacts another agent and of course it is impossible to call all the agents as a result of which the passenger also loses some options that were available but he was not able to exercise because he was not able to here she was not able to really handle all the options now this is from a passengers perspective that he was not able to exercise and all the options because it is impossible for him to exhaust all the available options and from a bus operators perspective because of this challenge at times invariably actually more often than not we have found that buses complained during the peak season also very rarely but it does happen and of course during the non peak seasons that their vacancy position is very alarming and the vacancy position would have been better if there was a mechanism by which a passenger is able to exhaust all the possible options now because that the passengers were not able to exhaust all the possible options there was vacancy in the buses as a result of which there was loss of revenue the another important challenge that both the bus operators as well as the passengers felt was the lack of transparency from the agents office because at times you know you know certain people who know some of the agents and they block seats for the VIPs or frequent travelers so at times you are not a frequent traveler but you have a very genuine reason to travel there might be seats available but because of the lack of transparency you know you do not get a seat that actually is available and when you actually want to travel you are denied a seat despite it being available for you to travel so there were these big challenges in that particular time frame that you had to depend dependence on agents I am just trying to highlight some of the major challenge and you can expand them later then passenger options restricted as a result of which revenue loss to bus operators and a major challenge was transparency lack of transparency which could also result to the revenue loss for the bus operators now these were the major challenges and remember when we were discussing about the SWAT analysis we were talking about how challenges we could see whether we can get some opportunities and use these challenges to provide a business solution now this is where the present case study becomes very relevant now what was happening in the ecosystem at that point of time that made the founders of a particular organization that we are going to discuss sees this opportunity they found that the online business booming not only the online business the entire online industry was maturing and a substantial part of it was driven by travel related business especially in India so there was an opportunity to create an organized mechanism an opportunity to create an organized mechanism in this bus transportation industry which was infested with a disorganized architecture information asymmetry there was no connect whatsoever between the passenger and the bus operator so the opportunity that the founders of this organization seized was to see how we could synergize very coherently the online business ecosystem and the need for an organized mechanism that is they felt that they could do this by using technology using technology and aggregating the industry the bus transportation industry to give an organized mechanism to provide an organized mechanism to provide an organized mechanism or in other words they wanted to bring all the passengers the bus operators everybody into a common transaction medium you could call that an exchange just like the stock market they wanted to bring all the passengers and the bus operators into a common transaction medium and in the process make the reservation the bus reservation a real time process make it a real time process as a result of which it becomes very transparent and since it is real time and since it is organized there is a lot of options available for the passengers not necessarily online but driven by an online solution for those who wanted to do offline booking telephone was there for those who did not have even internet connectivity they could use this telephone or and connect to the call centers so the organization found that there was this huge opportunity that it could encash by providing a synergy that could address the major challenges that the bus transportation industry was facing and this synergy rests on the creation of a technology that could aggregate the bus operators their seat position all the information that the bus operators could provide and provide this information to all the passengers who need this information as a result of which the entire bus ticketing process became very transparent and became independent of the agents involved so this organization that I am talking about is called the red bus I am sure many of you have used red bus in your ticketing process to undertake your travel I am sharing some of the insights that I got about this organization the case facts the different data from a case that was developed actually by the Richard Ivy business school university of western Ontario they did develop a case on this red bus as a case study discussion for its MBA students so back to this red bus so this is the organization the company the firm the online service provider this was the one that was founded and launched in 2006 by one gentleman by name from Indershamma who found in a very difficult position when he himself wanted to book a ticket to reach home on a festive occasion found it very difficult to get his own travel ticket and then came this idea of red bus to him and red bus was launched as a format independent bus ticketing company with a centralized inventory database providing online as well as offline bookings with a good distribution network so this is how they positioned red bus and the key words was it was format independent meaning that it could be for any type of bus operators it could be an AC bus non AC bus it could be a sleeper semi sleeper berth so all types of buses could be aggregated together and that it was a bus ticketing company it was only trying to provide a mechanism by which the entire ticketing process could be smoothened made better it was not in the business of running buses it was not in the business of opening agents office for bus operators and selling tickets it was it found itself a different model and established a different exchange that brought together passengers as well as the bus operators and how do they do that they build a centralized inventory database this centralized inventory database by inventory it contained information on the bus routes the bus the different bus service providers bus operators their routes the seed the availability position all this information on a real time basis as a result of which passengers could either book the tickets online through this central inventory database the red bus website or offline that they just had to call a red bus office or call their call centers which are using this red bus website I am going to explain how this entire thing happened so both the online as well as the offline option was available for passengers through available distribution network and they were able to provide both the B to B and B to C of course B to C was their main line business they provide this business to the consumers B to C means business to consumer they provide this business service to the consumers in this case the passengers as well as B to B in this case could be the bus operators as well as the online travel agents like the Yatra those types of travel agents for whom they gave a totally different service about which I will be talking a little later so what did red bus do how did they change the way in which the the way in which the entire bus transportation industry was behaving now for the bus operators it provided an application software that they called as boss the bus operators software system they call boss is the bus operators software system they sold it to the bus operators now each of the bus operator will have the software system at their workplace and they are connected to the centralized database which is a cloud database of red bus and what they do when connected to that is that they update all the information they update online the entire seat inventory by seat inventory it captures all the information like the availability of seats bus route price everything that is required for ticketing and for offline that is the non online bus operators those bus operators who could not afford this operation software they were able to connect over the phone and then provide inventory details inventory details over phone from offline bus operators and this get captured by the bus operators forward into the center inventory database by red bus own people and as I said the information meant the seats the routes the prices the seating type the bus design all that was captured on a real time basis this is one major change that it made the second thing that it made when you make change on the bus operators side there is a similar major change that you do for the travelers or the passengers that they built a very robust website red bus dot in so they provided a website an online service called red bus dot in so passengers who have internet connectivity just get logged on to this website which provides the information that it retrieves from the inventory database and the information to the inventory database is feed it from boss or fed into the database through phone telephonic updates that are collected by red bus employees from those bus operators operated on offline mode but in essence this website is the front end for the travelers and for those who do not have internet they can call the red bus call centers or red bus had their franchise on the bus operators outlets so you could go to the nearest franchise outlet and they will help you they go to the red bus website and get the ticketing process done the third thing that they also did was also for the OTAs these online travel agents you know there are some passengers who buy ad tickets book hotels book cabs through these OTAs now you see these make my trip likewise at that point of time the major OTAs that point of time was Expedia Yatra dot com so these were their OTAs to which red bus also gave a separate application called a seat seller a seat seller application and that was loaded in the OTAs website as an additional module in their online portal so that they themselves the OTAs themselves as part of their tour package could boot bus tickets using the seat seller application so this was this is what red bus did to change the way in which the bus ticketing was operational now if I try to capture this in a particular model as to give you an understanding how the presence system that red bus designed looks it would be like this so the central piece for this entire business model was the technology platform where you had all the database then you had the red bus website then you had call centers you had bus operator 1 2 3 up to N then you have passenger 1 passenger 2 N number of passengers and on the other side you also have the offline travel agents and the OTAs the online travel agents and you gave them the applications application plugins and this was through bus and for offline you could also capture through phone and put it in the central database and for the passengers they could get the information online from the technology platform or they could call them over the phone and get the ticketing done through call centers or they could in person visit the franchise outlets who will in turn get connected to the technology platform and get the ticketing done so in essence what used to be in the previous case if you look a few slides back it was very disorganized there was no connect between the passenger and the bus operator and everything had to run based on the agent's expertise assuming that the agent is transparent which he or she is not it was such a disorganized mechanism as a result of which passengers suffered the bus operators suffered due to huge revenue losses to an existing system that red bus implemented existing system of red bus where it brought together the entire stakeholders into the of the bus transportation industry together the centerpiece is the technology platform that it built and it is that technology platform that had the entire inventory database this is the information warehouse for this business model and that database it captured from the bus operators by selling them the boss application so that they could on a real time basis feed the information and for those who could not afford who chose to remain offline that information was captured through phone and again fed into the central inventory database and the information is ready to be consumed on the other hand by the passengers who wanted to buy tickets and they did not have to rely on these agents who could directly get into the website of red bus check availability pricing affordability by the tickets and make the travel or for those who do not have internet they could make a phone call get into the call center of red bus which again gets into this system and does the ticketing or they could go to the red buses franchised outlets or to the distribution centers and get the ticketing process done so this entire way in which the bus transportation industry changed was something that transformed the bus travel experience which in the olden days was just restricted to the time that you spent inside the bus during the travel which red bus transformed today the bus travel experience has started even before you undertake the travel the moment you log into the website you begin to feel the travelling experience checking various bus operators their seat design you get a look at the view of the bus the seating arrangement and also all sorts of combinations and the experience of travel you begin to feel even before you undertake to make the travel and red bus was very clear in segmenting its customers it handled them in five clear segments the private bus operators and they were able to build a network of around 800 private bus operators and they provided them a cloud based bus and of course they gave an alternate model for the offline this was their first customer segment the biggest of course was the in terms of volume was the passengers to whom red bus gave an internet option a call center option a telephonic option or even a distribution network where they could go and visit then the online travel agents as I said Expedia the aathra types where red bus gave the seat seller application and it also started very slowly to provide the sort of service even to state government bus agencies or bus departments whatever you call it because that itself is a big bus operator network every state government owns a fleet of buses so to say that that could be definitely a separate customer segment you have so many states each of them having their own transportation department as a result of which that was a clear separate customer segment for red bus another important not in terms of the business volume but in terms of the way in which the industry could be further characterized through a positive influence was through the bus manufacturers who primarily could rely on some data analytic tools that red bus develop because if you look at the present model that red bus built it is a data aggregator based on the bookings this bus manufacturers would know which are all the routes that are always high traffic which are all the type of seats that passengers prefer they know that if a particular passenger decides not to buy a particular seat and chooses a different bus operator because that particular seat design was available that bus manufacturers know that there is a demand for certain types of buses amongst the passenger amongst the passengers who use bus predominantly as a mode of transportation a variety of such you know data analysis can be done which will be an important critical feed to the bus manufacturers who themselves could take decisions for their own businesses now the customer value proposition that red bus was trying to deliver to each of these customers is very very important because what red bus tried to do was to disrupt the existing way of bus transportation and put in place something that is very very new and unless there is a very strong perception that this new model is going to deliver value it is very difficult for red bus to succeed so the customer value proposition that it gave you can you can see that from two perspectives but there is one unifying value that it gave to both the bus transporters the bus operators as well as the passengers was the the ecosystem that it built based on trust and transparency so this is in my view the key value proposition that red bus was delivering and this is true for both the bus operators as well as for the passengers that it built an ecosystem of trust and transparency and if you look at more specifically for bus operators the value proposition the potential to increase revenue that is a huge value proposition because they are into this business to make money and the propensity that this solution offered to increase in revenue was huge because the booking was real time the inventory was real time there is no way that you have passengers who need the seat but are not able to book them now this has really transformed the way in which business was done as a result of which there is increase in revenue for bus operators then there is timely payment of ticket sales because remember the red bus actually collects the money on behalf of the bus operators there is a timely payment so that is a value we do not have to rely on agents to get back the money there is no postponement delay then there is standardized commission the bus operators pay and this provided equal visibility to all bus operators gone are the days where agents prefer a set of bus operators and try to discard a few and they choose them as a lost option now in this case the key value proposition again it could be good for some bad for others but overall the equal visibility that it is able to provide to all the bus operators is also a value proposition then the data analytics as I said before is not only for the bus manufacturers even for the bus operators themselves they know which routes are profitable and if they find that more number of passengers require they could add more to the fleet serving that particular route so it is a very very critical value that bus operators can derive because of this new solution then you had online rating of bus operators so that they could improve their services and sometimes the relationship building between red bus and bus operators itself is an intrinsic value that this new model gave to the bus operators at times it could report ground you know field level feedback to the bus operators and help them in improving their efficiency and from the bus travelers perspective the key value proposition there might be some commonalities but the biggest one was as I said before the transparency and the ease at which they are able to get that tickets the reliability because if the system says there is no ticket you don't have to check with other agents it is a clear no so as a result of which you know passengers can begin to exercise other possible options it is real-time access it is real-time access it provided even the the route map pickup points delivery modes tickets could be delivered in the nearest delivery center or home delivery seat preference so it was kind of an all-in-one that the bus travelers were able to get from this service and for OTAs the major value proposition it was it was delivering was it was providing an access to the bus traveling tourists it provided an access to the bus traveling tourists so these were the major value proposition that red bus was able to give to the critical stakeholders the bus operators the bus travelers and the OTAs now what we need to see from here is the key success factors that made red bus successful and after it came into business after a substantial period of time they are at some crossroads to take a decision as to how they need to take this organization forward and that is where the strategy part comes into play first to understand what the key success factors were and after having made this reasonable success from here let us say after 6 years 7 years from 2005 6 where is red bus going to go what are the options that it has that it has to exercise to make sure that this success is further built into a sustainable competitive advantage as a result of which this organization red bus is able to meet the business objectives that it has in mind so for that part we will meet next class and see how from a strategic perspective red bus is able to take decision on its future course of action thank you


Kwa enkia maikua na mime. Ako jikiku kanawad za unikia mekanizimu kitbenu sani kama m집ivun kwa maikua na waka. Isuwa kwa mwa kwa mikua saku huwwat jika tijikwia hwenu, kwa mikru kwa hwenu kwa suko sellikia na msi ia mwye. Ja kuwia huj對了 jat ya maikua na mwye sebo batwCryo.  How many revisions do you have stored up in your database? It becomes heavy. Those particular revisions might not be usable. Now I'm going to show you just two tricks that can help you reduce the load on your databases in your system and also hope you optimize your site in just two lines of code. So I'm going to open up my WordPress site and I'll go into the root folder and I'll look up for the file which is called wpconfig.php. So I'll open that and when I open it, I have this file and it says here that I can start editing and I can add more code. So if I go to define a new constant and it's going to be called wp post revisions. Remember it's in plural and all I have to say is false. If I hit save on this because I've defined the wp post revisions as false, it means every time I save on my posts, I'm not going to have an auto-save. I'm going to be removing all the revisions that are available. I'm not going to allow my system to auto-save. Now that can be detrimental to you because like I said, this is supposed to be a fail-save system.  Now to avoid such an error, all you need to do is instead of having the revisions as false, you can set it as a number. So you could say, I only want to have three revisions of every post that I make. So you just need to add a number that is three. Now remember not to wrap it in quotes because that will make it a string. You're supposed to pass in a number, an integer. So once you do this, you'll only have three revisions of this post every time it's saved. It will auto-write the revision that's oldest and replace it with a new auto-save of the post. So this will allow your database to be a bit more optimum and also remove all the baggage that you will have stored over the long period of time. So if you enjoyed this trick, share it with others, subscribe to the channel if you think it's a good content that you're receiving, and turn on the notification bell so that you don't miss any new videos. So thank you for watching and enjoy your day.