Internetworking Data Communication between Various Systems - Coursework Example

Introduction: Internetworking means connecting more that one computer by using routing technology. In a network, routing technology used in all computers is same. Major purpose of Internetworking is sharing data and resources. Three types of networking exist. They are Local Area Network (LAN), Metropolitan Area Network (MAN), and Wide Area Network (WAN). Internetworking is a collection of LAN, MAN and WAN. In internetworking data communication between various systems is done based on certain protocols. Transport Control Protocol/ Internet Protocol (TCP/IP): TCP/IP is a reference model for the computer networks. It is also a protocol suite which includes several protocols for the communication between computers. It was introduced in one of the oldest wide area network - ARPANET. It is a widely used architecture because most of the computers and networks are configured to follow this suite and it is open to all. The TCP/IP reference model is a 4 layered model. The layers from top to bottom are Application Layer, Transport Layer, Internet Layer and Host-to-Network Layer. A data in a computer is going to the network from the Application Layer to the Host-to-Network Layer through the intermediate layers. Data from the network is getting to an application in the reverse order. Application Layer consists of certain higher level protocols like TELNET (for remote login/ to get a virtual remote terminal), FTP (File Transfer Protocol), SMTP (Simple Main Transfer Protocol), HTTP (Hyper Text Transfer Protocol), DNS (Domain Name System) protocols etc. The protocols in this layer will produce messages smaller in size to become compatible with the Transport Layer for an outward data flow and join the data messages to the original data for the application in case of inward message. Transport Layer consist the protocols like TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). The reliability and the error checking of the data are managed here. This layer is responsible for the communication between two computers. Internet Layer is responsible for the data communication between two networks in an internetworking. The data from the Transport Layer is broken into smaller IP packets. The main protocol used in this layer is IP (Internet Protocol). The two versions of IP are IPv4 and IPv6.The lowest layer is the Host-to-Network Layer and this layer has the direct contact with the networking hardware. The data in this layer will be in the form of frames or byte series. Few protocols like PPP (Point to Point Protocol) are available in this layer. One of the most useful services of TCP/IP is the naming service it provides. Information sharing and exchange on an Internet work become easy and comfortable through this. The most widely used naming services are NIS (Network Information Service) and DNS (Domain Name System). NIS is used to provide information that has to be known throughout the network, to all machines on the network. There will be NIS server to keep all the information for the NIS. In case of a UNIX system, the configuration files handled by NIS are /etc/group, /etc/hosts, /etc/netmasks, /etc/passwd, /etc/protocols, /etc/rpc, and /etc/services. For setting up NIS, we have to set up both the NIS Server and NIS Clients. DNS is used for naming a host uniquely on a network, especially on the Internet. In this IP addresses of the computers or other interfaces are mapped to certain names with a typical naming strategy. Each group of similar computers is included in same domain and the domains are created in a hierarchical manner e.g. for the top level domains are .com, .net, .org etc. The details of the naming are stored in the DNS Server as resource records. There are two types of mapping files. The forward mapping file is used to convert names to its IP addresses and reverse mapping record is used to convert IP addresses to its symbolic names. Format of a resource record entry is as follows. Name (variable length) type(16bits) class(16bits) ttl(32bits) data For DNS configuration in a UNIX system, we have to configure the files resolv.conf, named.conf, forward mapping file and reverse mapping file. UNIX Networking: UNIX is one of the important operating system in which lot of development is done. Because there are different versions of UNIX, there are different ways of programs to use networks from UNIX. Some common UNIX networking are given here. The internet:-It means a worldwide network of computers. By using it user can transfer files and login to the computers. Mail:-A UNIX program that has been around for years. So it is the same thing which is used in other operating system. File Transfer Protocol (FTP):-The FTP program is one way to transfer files between your computer and another computer with TCP/IP. UUCP:-UNIX-to-UNIX Copy is a family of programs for transferring files and email between computers. It is usually used with modems over telephone lines. Usenet:-Usenet is not exactly a network. It is a collection of thousands of computers worldwide that exchange files. Telnet:-This utility logs you into a remote computer over a network using TCP/IP. The telnet program is available on many operating systems; telnet can log you into other operating systems from your UNIX host and vice versa. (Unix Networking and Communications). Ethernet: Ethernet is a communication protocol in internetworking. It is used for the Local Area Networking. Ethernet cable is used for connecting different computers in the network to the central switch. This central switch is known as hub. Hub is used for the transmission of data packets between the computers in the LAN. Ethernet helps the sharing of various resources like printer and data in the network. Ethernet network may either be wired or wireless. In wireless Ethernet radio waves are used for communication. (What is Ethernet). Local Area Network (LAN) is used for connecting computers in a small geographical area. Examples are school, hospital, college, etc. Through LAN connection one can share resources like printer, plotter etc. It is very fast compared to MAN and WAN. In LAN all "Ethernet extenders can use fiber-optic or copper twisted-pair cables to transparently send packets at full-line rate to a peered LAN up to five miles away." (Have Questions: Why Use the Ethernet Extenders). Ethernet card is a network adapter. It operates in network with different speed. Ethernet card is used for setting high speed in the Ethernet. There are three types of Ethernet technologies. 1) Traditional Ethernet: - Its standard speed is 10Mbps (Mega bytes per second).Traditional Ethernet uses three type standards for connectivity.10Base-5, 10Base-2 and 10Base-T. 10Base-T is the commonly used Ethernet. In 10Base-T UTP (Unshielded Twisted Pair) cable is used for connecting the computers in the LAN. It is very cost effective cabling technique compared to the other two methods. It needs less segment length compared to others. So it is very popular in today's world. In traditional Ethernet segment length is very low. Through this Ethernet transmission is broken due to noise or degradation. Major disadvantage of traditional Internet is low performance and re-cabling. 2) Fast Ethernet: - Fast Ethernet overcomes the disadvantages of traditional Ethernet. Its standard speed is 100Mbps. It is in two types, 10Base-T and 10Base-FX. 10Base-T uses Unshielded Twisted Pair (UTP) cable for making connection.10Base-FX uses fiber optic cable for connection. 3) Gigabit Ethernet: - Its standard speed is 1000Mbps (1Gbps).1000Base-T standard support Gigabit Ethernet. (Mitchell). IEEE 802.3 is Ethernet protocol. According to IEEE 802.3 half duplex and full duplex are the two modes of operations done in Ethernet. In half duplex CSMA/CD (Carrier - Sense Multiple Access / Collision Detection) protocol is used for the data transmission. Major drawback of half duplex is less efficiency and limited coverage area. To overcome this limitation Gigabit Ethernet uses carrier extension technique. According to 802.3 operation speed on different Ethernet technologies are, in Traditional Ethernet it is 10 Mbps, in Fast Ethernet 100Mbps, and in Gigabit Ethernet 1Gbps. 7 1 6 6 2 46-1500bytes 4 Pre SFD DA SA Length Type Data unit + pad FCS (Ethernet: IEEE 802.3 Local Area Network (LAN) Protocols). This diagram illustrates the protocol structure of IEEE802.3 in Local Area Network. Here MAC (Media Access Control) data frame is used. MAC is developed based on CSMA/CD. MOD-TAP is an adapter. It is used to connect analogue telephone / modems to UTP networks. It helps to see to working phone system through the Ethernet cabling. Major features of Ethernet are:- a) Commonly it can send data 10 to 100 Mbps. b) It is a broadcast bus. Broadcasting means sending data from the source to all computers in the network. c) Best-effort delivery d) Distributed access control Interest Groups, Periodicals, and Conferences: Here it describes about electronic mail interest groups, networking periodicals, networking conferences, and other miscellaneous items in network. Electronic Mail is an important communication media in Internetworking where lot of people are communicating very efficiently. In the Email Interest groups we are mainly using mailing list. A list of people who subscribe to a periodic mailing distribution on a particular topic is called mailing list. It has become popular for internet users to keep up the topics they are interested. Mailing list means a collection of names and addresses used by an individual or an organization to send material to multiple recipients. The mail is sent to all the members who are included in the list. The moderator has full authority to filter the incoming mail and mail sent to the members. Usenet is another method which we are using. The Usenet System is a method of distributing electronic mail organized as a set of articles as a newsgroup. There are large number of Usenet groups related to TCP/IP, UNIX Usenet groups, Ethernet questions and information. Periodicals: We are using various Periodicals related to networking. It involves different Periodicals related to network which are published weekly, quarterly, monthly and yearly. Nowadays we are issuing electronic journal, which is easy to communicate and can be bought through credit card or through internet banking. Conference: Conference involves group of people who are interconnected through networks and they transmit the information at the same time. For conference we make use of PC networks and Mainframe networks. PC-Network is a network of computers which are connected together. There are different reasons for connecting together, such as sharing mails in different computers, sharing resources like printer to different computers and for administrative purpose like which resource is attached to which computer. Here we are using different network such as LAN, WAN and Internet. LAN means Local Area Network in which systems are connected through cables. It is mainly used in home, office, school, airport etc. WAN means Wide Area Network, which connects different cities. The connection is done by using special high speed lines leased from the phone company or through ordinary phone line using a device called modem. Another way to connect is through internet in which individual computers are connected through internet service provider (ISP). The original PC-Network hardware was available in two varieties, baseband and broadband. The baseband version connected computers using twisted-pair cables and it is less expensive. The broadband version is more expensive and less widely used. It has very good capacity to store data and handles wide range of frequencies. Mainframe technology involves large servers for handling high volume of transactions and input/output operations in parallel. In the case of Mainframe Technology, when the organization becomes larger, there may be the chances of higher cost due to failure. So, a fully functional backup site is made in this technology. So, mainly in conference, the different agencies are conducting the conference by TCP/IP experts and giving technical sessions relating to TCP/IP, UNIX networking and Ethernet issues. So, if any person wants to attend conference he can register in the community like INTEROP or USENIX and he can attend the conference. Access to the Internet: Nowadays accessing the internet is necessary to acquire knowledge. Organizations like schools, colleges and companies are connected to the internet for acquiring their required information. For getting internet connection one must meet the internet service provider. They will get service provider information through Internet user's guide and catalog. Conclusion: Internetworking is a very vast area. It is a technique used to connect the client to the server. Some key points related to this area are TCP/IP, Ethernet etc. Transport Control Protocol (TCP) is a protocol which confirms that the routing of the data from sender to receiver is done correctly and no damage happens to the messages. Data sent from one computer to another is in the form of packets. The process of transferring the data in the form of packets is called packet switching. Routing is the movement of packets from the source to the destination. Here data is sent in the form of datagram. Datagram is a packet sent through the network. For protecting the Internet work from frauds firewall is used. Works Cited Ethernet: IEEE 802.3 Local Area Network (LAN) Protocols. Javvin: Network Management and Security. 11 Mar. 2009. . Have Questions: Why Use the Ethernet Extenders. Patton Electronics. 2006. 11 Mar. 2009. . Kayne, R. What is Ethernet. Wise Geek. 2009. 11 Mar. 2009. . Mitchell, Bradley. Ethernet Tutorial. About.com: Wireless networking. 2009. 11 Mar. 2009. . Unix Networking and Communications. Unix Power Tools. 11 Mar. 2009. . Read More