By:

E. Susheel Chandar

M. Guna Sekaran

Intranet Mail Server

Modules• Authentic Server

• SMTP Server

• POP3 Server

• Chat Server

Authentic ServerAuthentic Server• This Module is used for the user to connect

to the mail server and also acts as the main server that gives the user the services of the SMTP and POP3 for sending and receiving mails , i.e. connects the user with the SMTP and the POP3 Server

Data Flow Diagram

User Interface

ClientExisting Users

New Users

AuthenticServer

UsrName and Pwd

Acknowledge

Acknowledge

Registration Req

Incorrect User Info

DataStore

SMTP Server

POP3Server

ChatServer

User Information

SMTP ServerSMTP Server• SMTP (Simple Mail Transfer Protocol) is

used for the purpose of sending mails to a particular user

• This SMTP Server implements the following set of the basic SMTP Commands which are sent from the host to send mails

Contd.. • HELO <domain>

– Returns identity of mail server.

• MAIL FROM <host> – Initiates a mail session from host.

• RCPT TO <user> – Designates who receives mail.

• DATA – Begins message composition.

• QUIT – Terminates the mail session.

• VRFY <user>– Verifies the identity of a user.

Contd..

• NOOP– Causes no action, except acknowledgement from server.

• RSET – Resets mail connection .

• The Response Codes from the server to the client for the requests are as follows

• 220 • Mail service ready.

• 250 • Mail transfer completed.

Contd..

• 354 – Start mail message, end with <CRLF><CRLF>.

• 221 – Mail service closing connection.

• 421 – Mail service unavailable.

• 450 – Mailbox unavailable.

• 500 – Unknown command.

• 501 – Bad parameter.

• 502 – Command not implemented.

Data Flow Diagram

ClientSMTP Server

HELO mgr.com

220

MAIL FROM <guna@mgr.com>

RCPT TO <susheel@mgr.com>

250

250

DATA (Welcome-----.)250

QUIT221

POP3 ServerPOP3 Server• POP3 (Post Office Protocol Version 3.0) is

used for the purpose of receiving or retrieving the mails for a particular user.

• The POP3 Server Implements the following set of basic Commands for the purpose of retrieval of mails

Contd..

• USER username– Sent by a client to identify the recipient.

• PASS password– Sent by a client to supply a password for the recipient.

• RETR index– Sent by a client to retrieve a specific message.

• DELE index– Sent by a client to delete a specific Message.

• QUIT– Sent by a client to sign off from the server.

Contd..

• Responses in a POP3 Server for the above requests or commands from the client is of only two types

• If the Request sent is correct the response usually begins with +OK <suffixes>

• If the Request sent is incorrect the response usually begins with –ERR < suffixes>

Data Flow Diagram

ClientPOP3Server

USER guna+OK password reqd for susheel@mgr.com

PASS cse+OK susheel@mgr.com has 2 message(s) ( 2000 octets)

RETR 2

+OK 340 octets Message ………….

DELE 1+OK Message 1 has been deleted

QUIT

+OK pop server at mgr.com signing off

Chat ServerChat Server

• This Module is used to implement a chat between two specific users who are online and also can initiate a conference chat between multiple users online

Data Flow Diagram

Client X Client Y

Server

Direct Connection Establishment

Chat Request

IP address of Client Y Chat Request

Response

Individual Chat :

Percentage of Completion

• Finished the Phases of analysis and Design of the Servers

• Implementation of SMTP and POP3 Servers in Process

• In Overall covered nearly 40 – 50 % of the Project

Future Enhancement

• To add facility of Voice Chat

THANK YOUTHANK YOU