PROTOCOLS, SUBSYSTEMS AND INTERNET APPLICATIONS

Protocols, Subsystems and Internet Applications

Protocols, Subsystems and Internet Applications

Part 1: Protocols and Subsystems

HTTP protocol

Since 1990, the protocol HTTP (Hypertext Transfer Protocol) is almost widely employed Internet protocol. Version 0.9 was only meant to transfer data all over the Internet. Version 1.0 of the protocol (used most) allows for the shift of messages with headers that depict the capacity of the contents by encrypting MIME (Jacobs, 2004).

The function of the HTTP protocol is to permit transfer of files (HTML mostly). Among a browser (client) and a web server set through a character string called address URL.

In reality, most communicating is done in stages if we consider the processing of the application on the server. Since we deal only HTTP protocol, not explain the processing on the server in this section of the article. If this topic interests you, please consult the article on the CGI treatment.

FTP

The FTP (File Transfer Protocol) is, as its name suggests, a protocol for transferring files.

The implementation of FTP back to 1971 when it developed a file transfer system (described in RFC 141) between teams from Massachusetts Institute of Technology (MIT, Massachusetts Institute of Technology. Since then, various RFC documents (Request for Comments) have improved the basic protocol, but the most important innovations took place in July 1973 (Clark, 2003).

Currently, the FTP protocol defined by RFC 959 (File Transfer Protocol (FTP)- Specifications).

FTP function

The FTP protocol defines how data should be transferred across a network TCP / IP.

The objective of the FTP protocol is:

Allow remote computers to share files

Allow independence between computer file systems and client server computer

Allow efficient data transfer (Kurose & Ross, 2010).

ARP protocol

The ARP protocol makes for a key role among Internet layer protocols relating to TCP / IP, allow knowing the physical address of a network user interface card representing to an IP address. Why it is called Address Resolution Protocol (ARP English means Address Resolution Protocol) (David, 2008).

RARP

To solve the first two issues of administration, the RARP protocol can be replaced by DRARP protocol, which is its dynamic version. Another approach is to use a DHCP (Host Configuration Protocol dynamic), allowing a dynamic resolution of addresses. In addition, the protocol supports DHCP BOOTP protocol (Protocol boot sequence) (Stevens & Wright, 2003).

ICMP protocol

Protocol (ICMP Internet Control Message Protocol) is a protocol that manages information related to errors on networked computers. Taking into account the lack of control that holds the IP protocol, ICMP cannot correct mistakes but that notifies surrounding layer protocols. Therefore, the ICMP protocol is used by all routers to indicate an error (called a delivery problem) (Forouzan, 2007).

IP address

Computers on a network use these addresses to communicate, so that each computer on the network has a unique IP address.

The agency in charge of allocating public IP addresses, i.e. IP addresses for computers connected directly to the public Internet, is ICANN (Internet Corporation for Assigned Names and Numbers) which replaces the IANA since 1998 (Internet Assigned Numbers Agency) (Smith & Lipner, ...