Computer Protocols

Computer Protocols

In today’s world, there are number of people communicating the number of different languages they use, the number of different machines they use, the number of ways in which they transmit data and the different software they use.

We would never be able to communicate worldwide if there were no ‘standards’ governing the way we communicate and the way our machines treat data. These standards are sets of rules.

There are rules governing how data is transferred over networks, how they are compressed, how they are presented on the screen and so on. These set of rules are called protocols. There are many protocols, each one governing the way a certain technology works. For example, the IP protocol defines a set of rules governing the way computers use IP packets to send data over the Internet or any other IP-based network. It also defines addressing in IP. Likewise, we have other protocols like:

• TCP: 

• Transmission Control Protocol, used for the reliable transmission of data over a network.

• HTTP:

•  Hypertext Transfer Protocol, used for transmitting and displaying information in the form of web pages on browsers.

• FTP: 

• File Transfer Protocol, used for file transfer (uploading and downloading) over the Internet.

• POP:

•  The most common protocol for receiving mail is Post Office Protocol (POP). It is now in version 3 so it is called POP3. Email clients such as Outlook Express require an address for a POP3 server before they can read mail. The SMTP and POP3 servers may or may not be the same address

• SMTP:

•  Simple Mail Transfer Protocol, used for email

• Both SMTP and POP3 use TCP for managing the transmission and delivery of mail across the Internet.

• Ethernet:

•  Used for data transmission over a LAN.

• Wi-Fi: 

• One of the wireless protocols.

• IP: 

• Internet Protocol is the primary network protocol used on the Internet, developed in the 1970s. On the Internet and many other networks, IP is often used together with the Transport Control Protocol (TCP) and referred to interchangeably as

• TCP/IP:

•  IP supports unique addressing for computers on a network. Most networks use the Internet Protocol version 4 (IPv4) standards that features IP addresses four bytes (32 bits) in length. The newer Internet Protocol version 6 (IPv6) standard features addresses 16 bytes (128 bits) in length.Data on an Internet Protocol network is organized into packets. Each IP packet includes both a header (that specifies source, destination, and other information about the data) and the message data itself.IP functions at layer 3 of the OSI model. It can therefore run on top of different data link interfaces including Ethernet and Wi-Fi.

• FTP:

•  File Transfer Protocol (FTP) lives up to its name and provides a method for copying files over a network from one computer to another. More generally, it provides for some simple file management on the contents of a remote computer. It is an old protocol and is used less than it was before the Word Wide Web came along. Today, its primary use is uploading files to a Web site. It can also be used for downloading from the Web but, more often than not, downloading is done via HTTP.

Function

The Internet Protocol is responsible for addressing hosts and for routing datagrams (packets) from a source host to a destination host across one or more IP networks. For this purpose, the Internet Protocol defines the format of packets and provides an addressing system that has two functions: identifying hosts; and providing a logical location service.

IP ADRESSING AND ROUTING

IP addressing entails the assignment of IP addresses and associated parameters to host interfaces. The address space is divided into networks and subnetworks, involving the designation of network or routing prefixes. IP routing is performed by all hosts, but most importantly by routers, which transport packets across network boundaries. Routers communicate with one another via specially designed routing protocols, either interior gateway protocols or exterior gateway protocols, as needed for the topology of the network.

IP routing is also common in local networks. For example, many Ethernet switches support IP multicast operations.These switches use IP addresses and Internet Group Management Protocol to control multicast routing but use MAC addresses for the actual routing

Security

During the design phase of the ARPANET and the early Internet, the security aspects and needs of a public, international network could not be adequately anticipated. Consequently, many Internet protocols exhibited vulnerabilities highlighted by network attacks and later security assessments. In 2008, a thorough security assessment and proposed mitigation of problems was published. The Internet Engineering Task Force (IETF) has been pursuing further studies