CS Engineering. Home Computer Sc. An application layer protocol defines how application processes clients and servers , running on different end systems, pass messages to each other.
In particular, an application layer protocol defines: The types of messages, e. The syntax of the various message types, i. The semantics of the fields, i. Users based on e-mail addresses.
SMTP provides services for mail exchange between users on the same or different computers. Both the client and server sides of SMTP run on every mail server.
working of mobile ip network - Mobile Computing - lec 41 - Bhanu priya
When a mail server sends mail to other mail servers , it acts as an SMTP client. When a mail server receives mail from other mail servers it acts as an SMTP server. On the server remote machine, NVT decodes the characters to a form acceptable to the remote machine.
TELNET is a protocol that provides a general, bi-directional, eight-bit byte oriented communications facility. FTP differs form other client-server applications because it establishes 2 connections between hosts. Two connections are: Data Connection and Control Connection.
FTP is built on a client-server architecture and uses separate control and data connections between the client and the server. One connection is used for data transfer, the other for control information commands and responses. It transfer data reliably and efficiently.
Content-Type: Header informs the receiving mail agent about the type of data included in the message. This is a protocol used by a mail server in conjunction with SMTP to receive and holds mail for hosts. POP3 mail server receives e-mails and filters them into the appropriate user folders.
When a user connects to the mail server to retrieve his mail, the messages are downloaded from mail server to the user's hard disk. The HTIP protocol transfer data in the form of plain text, hyper text, audio, video and so on. DNS is a hierarchical system, based on a distributed database, that uses a hierarchy of Name Servers to resolve Internet host names into the corresponding IP addresses required for packet routing by issuing a DNS query to a name server.
However, people refer to use names instead of address. Therefore, we need a system that can map a name to an address and conversely an address to name.
Domain name space is divided into three categories. Generic Domain: The generic domain defines registered hosts according, to their generic behaviour. Each node in the tree defines a domain which is an index to the domain name space database.
Country Domain: The country domain section follows the same format as the generic domain but uses 2 characters country abbreviations e.
Inverse Domain: The inverse domain is used to map an address to a name.
Tags : Computer Sc. Computer Networks. Aug 27 Computer Sc.
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