Networking Basics



The two most popular types of network cabling are twisted-pair (also known as 10BaseT) and thin coax (also known as 10Base2). 10BaseT cabling looks like ordinary telephone wire, except that it has 8 wires inside instead of 4. Thin coax looks like the copper coaxial cabling that’s often used to connect a VCR to a TV set.

Network Adapter:

A network computer is connected to the network cabling with a network interface card, (also called a “NIC”, “nick”, or network adapter). Some NICs are installed inside of a computer: the PC is opened up and a network card is plugged directly into one of the computer’s internal expansion slots. 286, 386, and many 486 computers have 16-bit slots, so a 16-bit NIC is needed. Faster computers, like high-speed 486s and Pentiums, , often have 32-bit, or PCI slots. These PCs require 32-bit NICs to achieve the fastest networking speeds possible for speed-critical applications like desktop video, multimedia, publishing, and databases. And if a computer is going to be used with a Fast Ethernet network, it will need a network adapter that supports 100Mbps data speeds as well.


The last piece of the networking puzzle is called a hub. A hub is a box that is used to gather groups of PCs together at a central location with 10BaseT cabling. If you’re networking a small group of computers together, you may be able to get by with a hub, some 10BaseT cables, and a handful of network adapters. Larger networks often use a thin coax “backbone” that connects a row of 10BaseT hubs together. Each hub, in turn, may connect a handful of computer together using 10BaseT cabling, which allows you to build networks of tens, hundreds, or thousands of nodes.
Like network cards, hubs are available in both standard (10Mbps) and Fast Ethernet (100Mbps) versions.

LANs (Local Area Networks)


WANs (Wide Area Networks)









Although each network protocol is different, they all share the same physical cabling. This common method of accessing the physical network allows multiple protocols to peacefully coexist over the network media, and allows the builder of a network to use common hardware for a variety of protocols. This concept is known as “protocol independence,” which means that devices that are compatible at the physical and data link layers allow the user to run many different protocols over the same medium.


A network topology is the geometric arrangement of nodes and cable links in a LAN, and is used in two general configurations: bus and star. These two topologies define how nodes are connected to one another. A node is an active device connected to the network, such as a computer or a printer. A node can also be a piece of networking equipment such as a hub, switch or a router. A bus topology consists of nodes linked together in a series with each node connected to a long cable or bus. Many nodes can tap into the bus and begin communication with all other nodes on that cable segment. A break anywhere in the cable will usually cause the entire segment to be inoperable until the break is repaired. Examples of bus topology include 10BASE2 and 10BASE5.
10BASE-T Ethernet and Fast Ethernet use a star topology, in which access is controlled by a central computer. Generally a computer is located at one end of the segment, and the other end is terminated in central location with a hub. Because UTP is often run in conjunction with telephone cabling, this central location can be a telephone closet or other area where it is convenient to connect the UTP segment to a backbone. The primary advantage of this type of network is reliability, for if one of these ‘point-to-point’ segments has a break, it will only affect the two nodes on that link. Other computer users on the network continue to operate as if that segment were nonexistent.

Peer-to-Peer Networks

A peer-to-peer network allows two or more PCs to pool their resources together. Individual resources like disk drives, CD-ROM drives, and even printers are transformed into shared, collective resources that are accessible from every PC.

Unlike client-server networks, where network information is stored on a centralized file server PC and made available to tens, hundreds, or thousands client PCs, the information stored across peer-to-peer networks is uniquely decentralized. Because peer-to-peer PCs have their own hard disk drives that are accessible by all computers, each PC acts as both a client (information requestor) and a server (information provider). A peer-to-peer network can be built with either 10BaseT cabling and a hub or with a thin coax backbone. 10BaseT is best for small workgroups of 16 or fewer users that don’t span long distances, or for workgroups that have one or more portable computers that may be disconnected from the network from time to time.

After the networking hardware has been installed, a peer-to-peer network software package must be installed onto all of the PCs. Such a package allows information to be transferred back and forth between the PCs, hard disks, and other devices when users request it. Popular peer-to-peer NOS software includes
Most NOSs allow each peer-to-peer user to determine which resources will be available for use by other users. Specific hard & floppy disk drives, directories or files, printers, and other resources can be attached or detached from the network via software. When one user’s disk has been configured so that it is “sharable”, it will usually appear as a new drive to the other users. In other words, if user A has an A and C drive on his computer, and user B configures his entire C drive as sharable, user A will suddenly have an A, C, and D drive (user A’s D drive is actually user B’s C drive). Directories work in a similar fashion. If user A has an A & C drive, and user B configures his “C:WINDOWS” and “C:DOS” directories as sharable, user A may suddenly have an A, C, D, and E
drive (user A’s D is user B’s C:WINDOWS, and E is user B’s C:DOS). Did you get all of that?

Because drives can be easily shared between peer-to-peer PCs, applications only need to be installed on one computer–not two or three. If users have one copy of Microsoft Word, for example, it can be installed on user A’s computer–and still used by user B.

· No need for a network administrator
· Network is fast/inexpensive to setup & maintain
· Each PC can make backup copies of its data to other PCs for security. By far the easiest type of network to build, peer-to-peer is perfect for both home and office use.

Client-Server Networks

In a client-server environment like Windows NT or Novell NetWare, files are stored on a centralized, high speed file server PC that is made available to client PCs. Network access speeds are usually faster than those found on peer-to-peer networks, which is reasonable given the vast numbers of clients that this architecture can support. Nearly all network services like printing and electronic mail are routed through the file server, which allows networking tasks to be tracked. Inefficient network segments can be reworked to make them faster, and users’ activities can be closely monitored. Public data and applications are stored on the file server, where they are run from client PCs’ locations, which makes upgrading software a simple task–network administrators can simply upgrade the applications stored on the file server, rather than having to physically upgrade each client PC.

In the client-server diagram below, the client PCs are shown to be separate and subordinate to the file server. The clients’ primary applications and files are stored in a common location. File servers are often set up so that each user on the network has access to his or her “own” directory, along with a range of “public” directories where applications are stored. If the two clients below want to communicate with each other, they must go through the file server to do it. A message from one client to another is first sent to the file server, where it is then routed to its destination. With tens or hundreds of client PCs, a file server is the only way to manage the often complex and simultaneous operations that large networks require.

Computer Networking is the very important and the crucial part of the Information Technology. Millions of the computers are networked together to form the Internet. Networking plays a important role in every kind of organization from small to medium sized, in Banks, Multinataional Companies, Stock Exchanges, Air Ports, Hospitals, Police Stations, Post Offices, Colleges, Universities, and even in home, in short networking plays an important role everywhere where computers are used. This article will be interesting for the students, network professionals and for the people who are interested in the computer networking