Basic Networking Part # 4

Protocols:Defination: A protocol is nothing more than a set of rules that that govern the format of messages so they can be exchanged successfully. A network protocol is a set of rules that allow for communication between network devices
Network protocols are standards that allow computers to communicate. A protocol defines how computers identify one another on a network, the form that the data should take in transit, and how this information is processed once it reaches its final destination. Protocols also define procedures for handling lost or damaged transmissions or "packets." TCP/IP (for UNIX, Windows NT, Windows 7 and other platforms), IPX (for Novell NetWare), Now Novell also using TCP/IP. DECnet (for networking Digital Equipment Corp. computers), AppleTalk (for Macintosh computers), and NetBIOS/NetBEUI (for LAN Manager and Windows NT networks, Windows Server 2003 or 2008) are the main types of network protocols in use today.

Although each network protocol is different, they all share the same physical cabling.Ethernet CAT5 or CAT6 or Fiber. 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,"

Some Important Protocols and their job:

	Finger DNS	Obtains information about a user from their profile. Domain Name Service: translates computer names into addresses and addresses into names.
	Whois	Obtains information about domain registration.
	Daytime	Network Time Protocol. Gets the time from a server.
	HTTP	Hypertext Transfer Protocol. Used for the Web.
	SMTP	Simple Mail Transfer Protocol. Used for sending email.
	POP	Post Office Protocol. Used for fetching email.
	FTP	File Transfer Protocol. Exchanges files with a server.
	NNTP	Network News Transfer Protocol. Posts or reads Usenet news.
	TCP	Transmission Control Protocol. Basic Internet protocol.
	UDP	User Datagram Protocol. Packet-based protocol.

Now I’ll disscuss the most important protocol suite known today from its wide usage in the Internet world is TCP/IP: Transmission Control Protocol (TCP) / Internet Protocol (IP).

Introduction to TCP/IP Networks:

TCP/IP-based networks play an increasingly important role in computer networks. Perhaps one reason for their appeal is that they are based on an open specification that is not controlled by any vendor.

What Is TCP/IP?TCP stands for Transmission Control Protocol and IP stands for Internet Protocol. The term TCP/IP is not limited just to these two protocols, however. Frequently, the term TCP/IP is used to refer to a group of protocols related to the TCP and IP protocols such as the User Datagram Protocol (UDP), File Transfer Protocol (FTP), Terminal Emulation Protocol (TELNET), and so on.

The Origins of TCP/IP (Basic of TCP/IP)In the late 1960s, DARPA (the Defense Advanced Research Project Agency), in the United States, noticed that there was a rapid proliferation of computers in military communications. Computers, because they can be easily programmed, provide flexibility in achieving network functions that is not available with other types of communications equipment. The computers then used in military communications were manufactured by different vendors and were designed to interoperate with computers from that vendor only. Vendors used proprietary protocols in their communications equipment. The military had a multi vendor network but no common protocol to support the heterogeneous equipment from different vendors.