By Won Lee Simple Mail Transfer Protocol SMTP
By Won Lee Simple Mail Transfer Protocol (SMTP)
What is SMTP? �Stands for Simple Mail Transfer Protocol �Used for sending and receiving electronic mail efficiently and reliably �Daily function of life �Used daily by the billions
History of SMTP �SMTP outgrew others in 1970’s. �Jonathan Postel wrote the SMTP definition in August 1982. �Documented under Request for Comments (RFC) 821 �Used by small collection of military, universities, and corporate research laboratories. �Connections were slow and unreliable but was only used by a handful of people.
Hist of SMTP (cont. ) �Number of hosts were recognizable by each other. �Focused on Reliability rather then Security. �People helped by configuring system to “open relay”. �Meaning a configured host would accept any mail meant for other systems and relay it to the mail’s final destination. �First spam in 1978 by Salesman from DEC
SMTP Specifications � SMTP mail transaction is a text-based protocol that is done in three steps. � Firstly, the transaction starts with a MAIL command that gives the sender identification. � Followed by a series of one or more RCPT commands, giving the receiver information. � Finally, a DATA command initiates transfer of the mail data and is terminated by the “end of mail” data indicator, which also confirms the transaction. � SMTP is mainly delivery protocol and uses POP 3 or IMAP to receive messages that’s being queued.
Visual Specification
Privacy � Not encrypted � Email passes through intermediate computer � Internet Service Provider (ISP) holds backup copies
Security � Rise of Con artists, hackers, & spammers � Wasn’t based on security to start with � Hard to retrofit a new security mechanism onto something widely used as SMTP.
Pervasiveness � Choice of easy and fast communication throughout the world. � 247 billions emails sent daily � 90 trillion sent in year 2009
Reliability � Was based on Reliability � Emails do get lost due to crowded and spammed servers � Unpredictable timeliness between sender & receiver
Interoperability � No point of emails if it’s not interoperable � Anywhere around the world � To any connected device (i. e. PC’s to Smart Phones)
Support of the Community � Anybody that is a member of the IETF � Has been updated many times in different RFCs � Shares ideas how to keep unwanted emails out (i. e. spam, hackers)
Ease of Use � So easy a kid can do it � User friendly software/interface � No coding necessary, unlike old times.
Application of SMTP �Almost any device with internet connectivity. �Web based mail: yahoomail, gmail, hotmail, and many more that nobody even heard of. �Software such as; Outlook Express, Mozilla Thunderbird, Iphone, Blackberry. �Can be used for personal or business use.
Conclusion �It’s makes life very easy to communicate with people around the world. �Fast, cheap, and easy to use. �Definitely be around in the future because of its convenience.
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