1. Social Media And Global Computing Sending Email

2. Using Databases with MVC
Visual Studio provides you with tools to create and send messages using SMTP. With this ability, comes the ability to create applications that communicate with users over , and that can even do verification to make sure the communications are with the actual owner of a given user account.

3. What is SMTP?
The de facto standard for transmissions across the Internet
It is defined in RFC 821
It is a relatively simple, text-based protocol
Not entirely secure thus vulnerable to SPAM

4. SMTP Originated in 1982 (Jon Postel)
Goal: To transfer mail reliably and efficiently

5. SMTP User Agent Mail Transfer Agents
SMTP clients and servers have two main components
User Agents – Prepares the message, encloses it in an envelope.
Mail Transfer Agent (MTA) – Transfers the mail across the internet
User Agent
Mail Transfer Agents

6. SMTP
SMTP also allows the use of Relays allowing other MTAs to relay the mail

7. What is Mail? Mail is a text file Envelope – Message – sender address
receiver address
other information
Message –
Mail Header – defines the sender, the receiver, the subject of the message, and some other information
Mail Body – Contains the actual information in the message

8. Post Office
Mailbox
Return-Path: Delivered-To:
Received: by mail.eecis.udel.edu (Postfix, from userid 62) id 17FBD328DE; Wed, 5 Nov :27:02
Received: from mail.acad.ece.udel.edu
(devil-rays.acad.ece.udel.edu [ ]) by mail.eecis.udel.edu (Postfix) with ESMTP id 5F for Wed, 5 Nov :27:01
Received: by mail.acad.ece.udel.edu (Postfix, from userid 62)id C; Wed, 5 Nov :27:01 Received: from stimpy.eecis.udel.edu(stimpy.eecis.udel.edu [ ])by mail.acad.ece.udel.edu (Postfix) with SMTP id 7C2943D79 for Wed, 5 Nov :26:34 Message-Id: Date: Wed, 5 Nov :26:34 From: To: undisclosed-recipients: ; MIME-Version: 1.0 This is a test.
Post office
and mail route
Receivers
Mailbox

9. How SMTP works The Essentials Keyword Arguments HELO
Sender’s Host Domain Name
MAIL FROM:
Address of sender
RCPT TO:
of Intended recipient
DATA
Body of the message
QUIT

10. Connection Establishment
TCP Connection Establishment

11. Problems with SMTP
No inherent security
Authentication
Encryption

12. E-mails can be forged….. HELO mail.rose.edu
MAIL FROM:
RCPT TO:
DATA
From: Dr. Art Zenner
To: Professor Richards
Subject: CIT 2243
Professor Richards,
By department decree all students in your “Introduction to Unix” class are hereby to be granted automatic A’s.
Thank you,
Dr. Art Zenner .
QUIT

13. SmtpClient Class
Provides services using the Simple Mail Transfer Protocol (SMTP).
Host field gets or sets the name or IP address for SMTP transactions with a server.
Port field gets or sets the port for SMTP transactions with a server.