Two of the most popular types of twisted pair cable network (also known as 10BaseT) and thin coax (also known as 10Base2).10BaseT cabling looks like ordinary telephone wire, except it has 8 son inside instead of 4. Thin coax looks like the copper coaxial cable that is often used to connect a VCR to a TV.
A computer network is connected to a wired network with a network interface card (also called a “NIC”, “Nick”, or network adapter). Some of the NIC is installed in the computer: the PC is opened and the network card connected directly to a computer expansion slots internally. 286, 386, 486 and the computer many 16-bit slots, so 16-bit NIC is needed. Faster computers, such as broadband and Pentium 486, often 32-bit slots, or PCI. These PCs require 32-bit NICs to achieve the fastest speed of the network to accelerate critical applications such as desktop video, multimedia, publishing, and database. And if the computer that will be used with a Fast Ethernet network, it will need a network adapter that supports 100Mbps data speeds as well.
The final piece of the puzzle is called a network hub. The hub is a box that serves to bring together groups of computers in a central location with 10BaseT cabling. If you are a small group of computers networked together, you can probably get by with a hub, some 10BaseT cables, and multiple network adapters.Major networks often use a thin coax “backbone” that connects a row of 10BaseT hubs together. Each pole, in turn, can connect multiple computers together with a 10BaseT cable, which allows you to build a network of dozens, hundreds or thousands of nodes.
Such as network cards, hubs are available in both standard Ethernet (10Mbps) and fast (100Mbps) versions.
LAN (Local Area Networks)
A network is a collection of independent computers that communicate with each other through shared network medium.LANs are networks usually confined to geographical areas, such as building or campus. LAN may be small, to connect at least three computers, but often link hundreds of computers used by thousands of people. Development of standard network protocols and media has led to the worldwide proliferation of LANs throughout business and educational organizations.
WAN (Wide Area Networks)
Often in the physical network. WAN combines multiple LANs that are geographically separated. This is done by connecting the local network using various services such as dedicated leased phone lines, dial-up telephone lines (both synchronous and asynchronous), satellite links and services to support packet data. WAN can be as simple as a modem and remote access server for employees to dial in, or be as complex as hundreds of branch offices globally linked using special routing protocols and filters to minimize the cost of delivery of data sent over vast distances.
The Internet is a network system that connects worldwide in scope and facilitate data communication services such as remote login, file transfer, electronic mail, World Wide Web and newsgroups.
With steep demand for connectivity, the Internet has become a communications highway for millions of users. The Internet was initially restricted to military and academic institutions, but now it is full of channels to form all the information and negotiation.Internet sites now offer personal, educational, political and economic resources to every corner of the planet.
With advances in browser-based software for the Internet, many private organizations to implement an intranet. An intranet is a private network that uses Internet-type tools, but is only available in the organization. For large companies, the intranet provides the user easy access to company information for employees.
Ethernet is a layer of physical LAN technology the most popular in use today. Other LAN types include Token Ring, Fast Ethernet, Fiber Distributed Data Interface (FDDI), Asynchronous Transfer Mode (ATM) and LocalTalk. Ethernet popular because it offers a good balance between speed, cost and ease of installation. These advantages, combined with wide acceptance in the computer market and the ability to support virtually all network protocols, make Ethernet an ideal networking technology for most users today. Institute of Electrical and Electronics Engineers (IEEE) defines the standard IEEE 802.3 Ethernet standard. This standard defines rules for configuring an Ethernet network and to determine how the elements of an Ethernet network interact with each other. Following the IEEE standard, network equipment and network protocols can communicate effectively.
Standard network protocol that allows computers to communicate. The protocol defines how computers identify one another on the network, the form that should take the data in transit, and how information is processed once it reaches its final destination. The protocol also defines procedures for handling lost or damaged transmissions or “packets”. TCP / IP (for UNIX, Windows NT, Windows 95 and other platforms), IPX (for Novell NetWare), DECnet (for networking computers Digital Equipment Corp.), AppleTalk (for Macintosh computers), and NetBIOS / NetBEUI (for LAN Manager and Windows NT networks) are the main types of network protocols in use today.
Although each network protocol is different, they all share the same physical cable. General method of access to the physical network allows multiple protocols to coexist peacefully and through the media network, and enables network builders to use materials common to various protocols. This concept is known as “protocol independence”, which means that the device is compatible with the physical layer and data link allows users to run many different protocols through the same medium.
A network topology is the geometric arrangement of nodes and links in the LAN cable, and is used in two general configurations: bus and star. These two topologies define how nodes are connected to each other. A node is an active device connected to a network, such as computers and printers. A node can also be part of the network equipment such as hubs, switches or routers. A bus topology consists of nodes connected in series with each node connected to a long cable or bus. Many nodes can take the bus and begin communication with all other nodes on the cable segment. A break anywhere in the cable is usually the cause the entire segment to be inoperable until the break repaired. Examples of bus topology include 10Base2 and 10Base5.
10Base-T Ethernet and Fast Ethernet use a star topology, where access is controlled by a central computer. Generally computers located at one end of the segment, and the other end terminated in a central location with a hub. Because UTP is often run in conjunction with a telephone cord, the central location may be a closet telephone or any other area where it will be easier to connect the UTP segment to the backbone. The main advantage of this type of network is reliability because if one of these segments “point to point” a break, it will only affect the two nodes on that link. Other computer users on the network will continue to operate as if the segment already exists.
A peer-to-peer allows two or more computers to share resources in common. Individual resources such as hard drives, CD-ROM drives, printers and even turned into a collective sharing of resources that can be accessed from any PC.
Unlike client-server networks, where network information is stored on a centralized file server PC and made available to tens, hundreds, thousands or PC client, the information stored in the peer-to-peer is particularly decentralized. Because peer-to-peer PCs have their own hard drive that is accessible by all computers, each PC acts as both a client (applicant information) and server (information provider). A peer-to-peer can be built with either 10BaseT cabling and a hub or a thin coax backbone.10BaseT is best for small groups of 16 or fewer users that do not extend over long distances, or for workgroups that have one or more laptops that can be disconnected from the network, from time to time .
Once the network hardware has been installed, software peer-to-peer must be installed in all PCs. Such a package allows information to be transferred back and forth between PCs, hard drives and other devices when users request it. Popular peer-to-peer NOS includes
Noss most allow each user to a peer-to-peer to determine the resources available for use by other users. Hard drives and diskettes particular, the directory or files, printers and other resources can be attached or separated from the network via software. When the disk is configured so that the user has “sharable”, it usually appears as a new drive for other users. In other words, if user A has drives A and C on the computer, and B the user to configure the entire C drive as sharable, user A will suddenly have the C and D drive (the user a D drive is actually user B C drive). Directories work the same way. If a user has a disk D & C, and B the user to configure the “C: WINDOWS” and “C: DOS” directories sharable, user A may suddenly have the A, C, D and E
disks (the user is the user AD BC: WINDOWS, and E is the BC user: DOS). Did you this?
Because the reader can be easily shared between peer-to-peer PCs, applications must be installed on a computer – not two or three. If the user has a copy of Microsoft Word, for example, can be installed on a user’s computer – and is still used by user B.
The advantage of peer-to-peer through a client-server Noss include:
• No need for network administrators
· Network fast / inexpensive to install and maintain
• Each PC can make backup copies of data to another PC for security. Is by far the simplest type of building peer-to-peer is perfect for home and office.
In client-server environment like Windows NT or Novell NetWare, files are stored on a centralized file server PC high speed are available to client PCs. Network access speeds are generally faster than those found on peer-to-peer, which is reasonable given the large number of clients that can support this architecture. Nearly all network services such as printing and e-mail sent via the file server, which allows networking tasks to be tracked. Inefficient network segments can be reworked to make them faster, and user activity can be closely monitored. Public data and applications stored on the file server, where they fled from the scene of client PCs’ 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 client-server diagram below, the client PC separately and subject to the file server. The main application file is stored on the client and the general location. File servers are often arranged so that each user on the network have access to a “clean” in his repertoire, with different “public” directories where applications are stored. If two clients below want to communicate with each other, they must go through the file server to do so. A message from one client to another was first sent to a file server, where it is then forwarded to the destination. With dozens or hundreds of workstations, file servers is the only way to manage the often complex and simultaneous operations that require large networks.
The computer network is a very important and vital of information technology. Millions of computers are linked together to form the Internet. Network plays an important role in any organization from small to medium, to the Bank, the Company Multinataional, scholarships, airports, hospitals, police, post office, schools, universities, and even at home, in a brief network plays an important role wherever computers are used. This article will appeal to students, professional networks and people who are interested in computer networks.