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DELNET
DELNET was started at the India International Centre Library in January 1988 and was
registered as a society in 1992. It was initially supported by the National Information System for
Science and Technology (NISSAT), Department of Scientific and Industrial Reseach,
Government of India. It was subsequently supported by the National Informatics Centre,Department of Information Technology, Ministry of Communications and Information
Technology, Government of India and The Ministry of Culture, Government of India.
DELNET has been established with the prime objective of promoting resource sharing among
the libraries through the development of a network of libraries. It aims to collect, store, and
disseminate information besides offering computerised services to users, to coordinate efforts
for suitable collection development and also to reduce unnecessary duplication wherever
possible.
DELNET has been actively engaged with the compilation of various Union Catalogues of the
resources available in member-libraries.It has already created the Union Catalogue ofBooks,Union List of Current Periodicals, Union Catalogue of Periodicals,CD-ROM
Database,Database of Indian Specialists, Database of Periodical Articles, Union List of Video
Recordings, Urdu Manuscripts' Database, Database of Theses and Dissertations, sample
databases of language publications using GIST technology and several other databases. The
data is being updated in each of these databases and is growing rapidly. All the DELNET
databases have been resident on DELSIS, an in-house software developed on BASISPlus, an
RDBMS, the product of Information Dimensions Inc. of USA which has been provided to
DELNET courtesy National Informatics Centre, New Delhi.
DELNET provides an array of facilities including E-mail to its member-libraries including both
institutional and associate institutional members. DELNET'S relentless efforts in resource
sharing have proved extremely effective. It has indeed been a big leap towards the
modernisation of libraries in India.
OBJECTIVES
The Main Objectives of DELNET are :
To promote sharing of resources among the libraries by developing a network oflibraries, by collecting, storing and disseminating information and by offering
computerised services to the users;
To undertake scientific research in the area of Information Science and Technology,create new systems in the field, apply the results of research and publish them;
To offer technical guidance to the member-libraries on collecting, storing, sharing anddisseminating information;
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To coordinate efforts for suitable collection development and reduce unnecessary duplicationwherever possible;
To establish /facilitate the establishment of referral and /or research centres, and maintain acentral online union catalogue of books, serials and non-book materials of all the participatinglibraries;
To faciliate and promote delivery of documents manually or mechanically;
To develop specialised bibliographic database of books, serials and non-book materials;
To develop databases of projects, specialists and institutions;
To possess and maintain electronic and mechanical equipment for speedy communication ofinformation and delivery of electronic mail;
To coordinate with other regional, national and international networks and libraries for exchangeof information and documents.
SERVICES
1. Access To Databases
DELNET Databases
a) Union Catalogue of Books DELNET maintains an online union catalogue of books available in its member-libraries. This unioncatalogue is continuously updated and is growing in size. The information can be retrieved byauthor, title, subject, conference, series, etc. It has 83,69,299 bibliographic records. The requestfor inter-library loan can be placed through the online system.
b) Union List of Current Periodicals DELNET has created union lists of current periodicals in science and technology, social sciencesand humanities. This database is available online to DELNET users. It now lists 33,541 periodicalsand is regularly updated and new titles are added annually. It is a major resource for DocumentDelivery Services.
c) Union Catalogue of Periodicals DELNET maintains a union catalogue of periodicals, which contains full holdings data of thelibraries. At present, the database contains 20,235 records.
d) Database of Periodical Articles The database has details of articles which can be searched under the title, author, compiler, nameof the periodical and subject. The database is being extensively utilised by the researchers andscholars. At present the database contains 9,12,042 records.
e) CD-ROM Database A bibliographic database of CD-ROMs available with the member-libraries is being compiled. It has11,715 records.
f) Union List of Video Recordings
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This is a database of video cassettes available in DELNET member-libraries and has about 5,000listings.
g) Union List of Sound Recordings This union list consists of audio cassette records available in member-libraries. This database has748 records.
h) Database of Theses and Dissertations A database of Theses and Dissertations submitted to Indian Universities has been started, whichcovers various subjects. The database has 44,304 records.
i) Union List of Newspapers The database has 70 records and contains information about the newspapers including title, nameof the editor, published from, E-mail address and also the Web address of the INTERNET edition ifavailable on the WWW.
j) Database of E-books It has nearly 1613 records.
k) Profile of Member-Libraries A directory of member-libraries is available and contains information about them.
II Delnet also provides access to
a. Cambridge Dictionaries onlineb. Networked Digital Library of Theses and Dissertationsc. ODLIS : Online Dictionary of Library & Information Scienced. GISTNIC Databases
e. MEDLINE & other databases of NLMf. U.S. Patents: Full Textg. Full Text Medical Journalsh. Open Access Journalsi. Engineering & Technology E-Journals: Table of Contentsj. Full-Text Medical Books k. Full-Text Engineering & Technology E-journalsl. Learning Resources for LIS Professionalsm. Digital Libraries of the World
2.Loan and Delivery
DELNET Loan And Document Delivery Services
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DELNET is offering inter-Library loan & Document Delivery Services to its member libraries. ILLrequests can be registered online for books. For the resources not available in the unioncatalogues and journal articles, requests can be sent to DELNET through E-mail. DELNET hasalso prepared ILL Guidelines for use by the member-libraries. The services are quite popularamong the member-libraries
ILL Online (for members in Delhi).Rs. 4,000/- per year. Actual photocopying charges,if any, and courier/postal charges for booksprocured from outside Delhi will be extra.
ILL Online (for members outside Delhi) Rs. 4,000/- per year. Actual photocopyingcharges,and courier charges will be charges,andcourier charges will be charges,and courier chargeswill be extra.
3.Retro Conversion
DELNET undertakes retro-conversion projects periodically.
4.Reference Services
DELNET maintains a referral centre which provides reference facilit ies to part icipat inglibraries. This also looks after the access to the central databases and provides promptreplies.
5.Professional Service/Training
DELNET arranges tutorials, workshops, lectures, and training programmes every year from timeto time besides the National Convention on Knowledge, Library and Information Networking(NACLIN).
DELNET also offers online information on :
Announcements of the International Federation of Library Associations and Institutions (IFLA)and Library Science jobs globally. This information provides inputs to library and information
professionals for improving their talent and professional expertise.
6.Technical Support
DELNET adopts the latest dependable technologies in information science. This helps librariesto get advice from DELNET to adopt technologies that emerge periodically. This savesexpenses and time of the member-institutions.
DELNET offers technical support to member institutions in the selection of:
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a. Hardware
b. Software
c. Communication Links
d. Database Creation; and
e. Technical problems faced by member-libraries from time to time
PUBLICATIONS
NACLIN Proceedings
NEWSLETTERS
DIRECTOR’S Report
Other Publications
RESEARCH
DELNET has been conducting research in the following areas from its inception:
a. Use of International Standards
DELNET was the first institution in India to introduce MARC 21 standards among the libraries.Special training programmes are also organised from time to time in the use of MARC 21Standard.
b. Open Source Software
DELNET is giving training in the use of KOHA - an Open Source Integrated Library System andDspace for building Digital Libraries. DELNET is glad to provide consultancy to the libraries onimplementing these Open Source Software.
c. National Bibliographic Database
DELNET undertook the compilation of the National Bibliographic Database with the support of theDepartment of Culture, Government of India in 1998 as a Pilot Project. Fifty thousand records ofbooks: 20,000 in English, 15,000 in Tamil and 15,000 in Punjabi were created at the PunjabiUniversity, Patiala and International Institute of Tamil Studies, Chennai. At Andhra UniversityLibrary, Visakhapatnam, 15,000 records in English and 10,000 records in Telugu were alsocreated. Similarly 25,000 records each were created at the Asiatic Society, Mumbai and theAsiatic Society, Kolkata.
d. Creation of Union Catalogues and Union Lists
DELNET has been creating research tools for scholars and users in the form of union cataloguesand union lists and these are widely used. The details are given in the section on Services.
LATEST PROGRAMMES
Orientation Programme held at GLAITM, Mathura on July 29, 2010
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National Convention on Knowledge, Library and Information Networking (NACLIN 2010) DELNET Annual Lecture on "Robotics and Artificial Intelligence", held at IIC on May 11,
2010 DELNET Workshop on Koha : An Open-Source Integrated Library System, held at
DELNET, New Delhi from May 3-5, 2010 DELNET Workshop on Dspace for Building Digital Libraries, held at DELNET, New Delhi
from April 28-30, 2010 Lecture on Advocating for the Value of Information Professionals in the Workplace, held
at IIC on October 7, 2009. National Convention on Knowledge, Library and Information Networking (NACLIN 2009) Lecture on Information Literacy Competencies : New Directions, held at IIC Annexe
(Lecture Hall ) on August 6, 2009. "Three Days Workshop on Modernisation of College Libraries in the State of J&K"
organised by DELNET in collaboration with Department of Library and InformationScience, University of Kashmir, Srinagar, July 27-29, 2009
Orientation Programmes-
May 21,2009-Amrita School of Engineering,Bangalore,
May 23, 2009 - S. R. M. University, Kattankulathur
June 05, 2009 - Visva-Bharati University, Santiniketan
Regional Workshops on KOHA - An Open-Source Integrated Library System (ILS) : AnIdeal Opportunity for Libraries, held at Amrita School of Engineering, Bangalore
DELNET Annual Lecture on "Information Dissemination in New Generation Networks -Opportunities and Challenges", held at IIC on March 5, 2009.
DELNET INITIATIVES
National Bibliographic Databases
DELNET undertook the compilation of the National Bibliographic Database with the support ofthe Department of Culture, Government of India in 1998 as a Pilot Project. Fifty thousandrecords of books: 20,000 in English, 15,000 in Tamil and 15,000 in Punjabi were created at thePunjabi University, Patiala and International Institute of Tamil Studies, Chennai. At AndhraUniversity Library, Visakhapatnam, 15,000 records in English and 10,000 records in Teluguhave also been created. Similarly 25,000 records have been created at the Asiatic Society,Mumbai. The work is in progress at the Asiatic Society, Kolkata.
Knowledge Centres
DELNET proposes to get Knowledge Centres established in India with the support of theGovernment of India and the State Governments. The computer and communicationtechnologies can help in networking knowledge and people in complex permutations andcombinations provided we have the desired content and the requirements of users availablewith us in machine readable form. We also will have to use the Knowledge Technology to makebest use of limited resources of knowledge in the country. The Knowledge Technology does notmerely help in matching users needs with knowledge resources, but also helps in takingdecisions in global and futuristic perspectives.
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Keeping in view the importance of Knowledge Centres, DELNET proposes that KnowledgeCentres should be established in public libraries and the centres of learning in each state. Also,it is planning to establish the National Knowledge Centre at DELNET.
The National Knowledge Centre would make knowledge accessible through the KnowledgeGateway www.knowledgegateway.org It will also promote the creation of suitable content at
the Knowledge Centres and make it available to the public in the country. It will add links toevery useful information that is already existing and make all knowledge available to the public,including researchers, students and teachers.
Telnet
TELNET is a network protocol used on the Internet or local area networks to provide abidirectional interactive text-oriented communications facility via a virtual terminal connection.User data is interspersed in-band with TELNET control information in an 8-bit byte oriented data
connection over the Transmission Control Protocol (TCP).
Telnet was developed in 1969 beginning with RFC 15, extended in RFC 854, and standardizedas Internet Engineering Task Force (IETF) Internet Standard STD 8, one of the first Internetstandards.
Historically, telnet provided access to a command-line interface (usually, of an operatingsystem) on a remote host. Most network equipment and operating systems with a TCP/IP stacksupport a Telnet service for remote configuration (including systems based on Windows NT).Because of security issues with Telnet, its use for this purpose has waned in favor of SSH.
The term telnet may also refer to the software that implements the client part of the protocol.
Telnet client applications are available for virtually all computer platforms. Telnet is also used asa verb. To telnet means to establish a connection with the Telnet protocol, either with commandline client or with a programmatic interface. For example, a common directive might be: " To change your password, telnet to the server, login and run the passwd command." Most often, auser will be telnetting to a Unix-like server system or a network device (such as a router) andobtain a login prompt to a command line text interface or a character-based full-screenmanager.
History and standards
Telnet is a client-server protocol, based on a reliable connection-oriented transport. Typically
this protocol is used to establish a connection to Transmission Control Protocol (TCP) portnumber 23, where a Telnet server application (telnetd) is listening. Telnet, however, predatesTCP/IP and was originally run over Network Control Program (NCP) protocols.
Before March 5, 1973, Telnet was an ad-hoc protocol with no official definition.[1] Essentially, itused an 8-bit channel to exchange 7-bit ASCII data. Any byte with the high bit set was a specialTelnet character. On March 5, 1973, a Telnet protocol standard was defined at UCLA [2] with thepublication of two NIC documents: Telnet Protocol Specification, NIC #15372, and Telnet OptionSpecifications, NIC #15373.
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Because of "negotiable options" protocol architecture, many extensions were made for it, someof which have been adopted as Internet standards, IETF documents STD 27 through STD 32.Some extensions have been widely implemented and others are proposed standards on theIETF standards track (see below).
Security
When Telnet was initially developed in 1969, most users of networked computers were in thecomputer departments of academic institutions, or at large private and government researchfacilities. In this environment, security was not nearly as much of a concern as it became afterthe bandwidth explosion of the 1990s. The rise in the number of people with access to theInternet, and by extension, the number of people attempting to crack other people's serversmade encrypted alternatives much more of a necessity.
Experts in computer security, such as SANS Institute, recommend that the use of Telnet forremote logins should be discontinued under all normal circumstances, for the following reasons:
Telnet, by default, does not encrypt any data sent over the connection (includingpasswords), and so it is often practical to eavesdrop on the communications and use thepassword later for malicious purposes; anybody who has access to a router, switch, hubor gateway located on the network between the two hosts where Telnet is being usedcan intercept the packets passing by and obtain login and password information (andwhatever else is typed) with any of several common utilities like tcpdump and Wireshark.
Most implementations of Telnet have no authentication that would ensurecommunication is carried out between the two desired hosts and not intercepted in themiddle.
Commonly used Telnet daemons have several vulnerabilities discovered over the years.
These security-related shortcomings have seen the usage of the Telnet protocol drop rapidly,
especially on the public Internet, in favor of the Secure Shell (SSH) protocol, first released in1995. SSH provides much of the functionality of telnet, with the addition of strong encryption toprevent sensitive data such as passwords from being intercepted, and public key authentication,to ensure that the remote computer is actually who it claims to be. As has happened with otherearly Internet protocols, extensions to the Telnet protocol provide Transport Layer Security(TLS) security and Simple Authentication and Security Layer (SASL) authentication that addressthe above issues. However, most Telnet implementations do not support these extensions; andthere has been relatively little interest in implementing these as SSH is adequate for mostpurposes. The main advantage of TLS-Telnet would be the ability to use certificate-authoritysigned server certificates to authenticate a server host to a client that does not yet have theserver key stored. In SSH, there is a weakness in that the user must trust the first session to ahost when it has not yet acquired the server key.
Telnet 5250
IBM 5250 or 3270 workstation emulation is supported via custom telnet clients,TN5250 /TN3270, and IBM servers. Clients and servers designed to pass IBM 5250 datastreams over Telnet generally do support SSL encryption, as SSH does not include 5250emulation. Under OS/400, port 992 is the default port for secured telnet.
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Telnet data
All data octets except \377 are transmitted over the TCP transport as is. Therefore, a Telnetclient application may also be used to establish an interactive raw TCP session, and it iscommonly believed that such session which does not use the IAC (\377 character, or 255 indecimal) is functionally identical]This is not the case, however, because there are other network virtual terminal (NVT) rules, such as the requirement for a bare carriage return character (CR,ASCII 13) to be followed by a NULL (ASCII 0) character, that distinguish the telnet protocol fromraw TCP sessions. On the other hand, many systems now possess true raw TCP clients, suchas netcat or socat on UNIX and PuTTY on Windows, which also can be used to manually "talk"to other services without specialized client software. Nevertheless, Telnet is still sometimesused in debugging network services,such as SMTP, IRC, HTTP, FTP or POP3 servers, to issuecommands to a server and examine the responses, but of all these protocols only FTP reallyuses Telnet data format.
Another difference of Telnet from a raw TCP session is that Telnet is not 8-bit clean by default.8-bit mode may be negotiated, but high-bit-set octets may be garbled until this mode was
requested, and it obviously will not be requested in non-Telnet connection. The 8-bit mode (sonamed binary option ) is intended to transmit binary data, not characters though. The standardsuggests the interpretation of codes \000 – \176 as ASCII, but does not offer any meaning forhigh-bit-set data octets. There was an attempt to introduce a switchable character encodingsupport like HTTP has,[3] but nothing is known about its actual software support.
Current status
As of mid-2010, the Telnet protocol itself has been mostly superseded for remote login. Telnet ispopular in various application areas:
Enterprise networks to access host applications, e.g., on IBM Mainframes. Administration of network elements, e.g., in commissioning, integration and maintenance
of core network elements in mobile communication networks, and many industrial controlsystems.
MUD games played over the Internet, as well as talkers, MUSHes, MUCKs, MOOes, and the resurgent BBS community.
Internet game clubs, like the Internet Chess Club, the Free Internet Chess Server andthe Internet Go server.
Embedded systems. Mobile data collection applications where telnet runs over secure networks Collaboration of multiple users where the capability of session transfer, swap, sharing,
and recovery of disconnected sessions is needed.[4]
Also note that Telnet is a component of FTP protocol. FTP control data are transmitted in Telnetformat, although some software implements it incorrectly.
Related RFCs
RFC 137, TELNET protocol specification RFC 139, TELNET protocol specification RFC 854, TELNET protocol specification
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RFC 855, TELNET option specifications RFC 856, TELNET binary transmission RFC 857, TELNET echo option RFC 858, TELNET suppress Go Ahead option RFC 859, TELNET status option RFC 860, TELNET timing mark option RFC 861, TELNET extended options - list option RFC 885, Telnet end of record option RFC 1041, Telnet 3270 regime option RFC 1073, Telnet Window Size Option RFC 1079, Telnet terminal speed option RFC 1091, Telnet terminal-type option RFC 1096, Telnet X display location option RFC 1184, Telnet linemode option RFC 1205, 5250 Telnet interface RFC 1372, Telnet remote flow control option RFC 1572, Telnet Environment Option RFC 2217, Telnet Com Port Control Option RFC 2941, Telnet Authentication Option RFC 2942, Telnet Authentication: Kerberos Version 5 RFC 2943, TELNET Authentication Using DSA RFC 2944, Telnet Authentication: SRP RFC 2946, Telnet Data Encryption Option RFC 4248, The telnet URI Scheme RFC 4777, IBM's iSeries Telnet Enhancements
Telnet clients
PuTTY is a free, open source SSH, Telnet, rlogin, and raw TCP client for Windows, Linux, and Unix.
AbsoluteTelnet is a telnet client for Windows. It also supports SSH and SFTP, Host Explorer part of Hummingbird Connectivity; it implements the telnet, TN 3270,
5250, Ansi, and other protocols. RUMBA (Terminal Emulator) IVT VT 220 Line Mode Browser, a command line web browser NCSA Telnet TeraTerm Passport from Zephyr Corp, available as both regular executables and a web-based
SSH/Telnet application SecureCRT from Van Dyke Software TeSSH from Zugg Software for Windows based upon the zMUD and CMUD code base
also supports SSH and SFTP ZOC SSH client SyncTERM BBS terminal program supporting Telnet, SSHv2, RLogin, Serial, Windows,
*nix, and Mac OS X platforms, X/Y/ZMODEM and various BBS terminal emulations.
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Wide area network
A wide area network (WAN) is a computer network that covers a broad area (i.e., any networkwhose communications links cross metropolitan, regional, or national boundaries [1]). This is incontrast with personal area networks (PANs), local area networks (LANs), campus areanetworks (CANs), or metropolitan area networks (MANs) which are usually limited to a room,building, campus or specific metropolitan area (e.g., a city) respectively.
WAN design options
WANs are used to connect LANs and other types of networks together, so that users andcomputers in one location can communicate with users and computers in other locations. ManyWANs are built for one particular organization and are private. Others, built by Internet serviceproviders, provide connections from an organization's LAN to the Internet. WANs are often builtusing leased lines. At each end of the leased line, a router connects to the LAN on one side anda hub within the WAN on the other. Leased lines can be very expensive. Instead of using leased
lines, WANs can also be built using less costly circuit switching or packet switching methods.Network protocols including TCP/IP deliver transport and addressing functions. Protocolsincluding Packet over SONET/SDH, MPLS, ATM and Frame relay are often used by serviceproviders to deliver the links that are used in WANs. X.25 was an important early WAN protocol,and is often considered to be the "grandfather" of Frame Relay as many of the underlyingprotocols and functions of X.25 are still in use today (with upgrades) by Frame Relay.
Academic research into wide area networks can be broken down into three areas: Mathematicalmodels, network emulation and network simulation.
Performance improvements are sometimes delivered via WAFS or WAN optimization.
WAN connection technology options
There are also several ways to connect NonStop S-series servers to WANs, including via theServerNet Wide Area Network (SWAN) or SWAN 2 concentrator, which provides WAN clientconnectivity to servers that have Ethernet ports and appropriate communications software. Youcan also use the Asynchronous Wide Area Network (AWAN) access server, which offerseconomical asynchronous-only WAN access. Several options are available for WANconnectivity:[2]
Option: Description Advantages DisadvantagesBandwidth
range
Sample
protocols
used
Leased
line
Point-to-Point connection
between two computers or
Local Area Networks
(LANs)
Most secure Expensive
PPP,
HDLC,
SDLC,
HNAS
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Circuit
switching
A dedicated circuit path is
created between end
points. Best example is
dialup connections
Less
ExpensiveCall Setup
28 - 144
kbit/sPPP, ISDN
Packet
switching
Devices transport packetsvia a shared single point-
to-point or point-to-
multipoint link across a
carrier internetwork.
Variable length packets
are transmitted over
Permanent Virtual Circuits
(PVC) or Switched Virtual
Circuits (SVC)
Shared media
across link
X.25
Frame-
Relay
Cell relay
Similar to packet
switching, but uses fixed
length cells instead of
variable length packets.
Data is divided into fixed-
length cells and then
transported across virtual
circuits
Best for
simultaneous
use of voice
and data
Overhead can
be considerableATM
Transmission rates usually range from 1200 bit/s to 24 Mbit/s, although some connections suchas ATM and Leased lines can reach speeds greater than 156 Mbit/s. Typical communicationlinks used in WANs are telephone lines, microwave links & satellite channels.
Recently with the proliferation of low cost of Internet connectivity many companies andorganizations have turned to VPN to interconnect their networks, creating a WAN in that way.Companies such as Cisco, New Edge Networks and Check Point offer solutions to create VPNnetworks.
EmailFrom Wikipedia, the free encyclopedia
(Redirected from Electronic mail)
Jump to: navigation, search
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For the former manufacturing conglomerate, see Email Limited .
The at sign, a part of every e-mail address[1]
Electronic mail, commonly called email or e-mail, is a method of exchanging digital messagesacross the Internet or other computer networks. Originally, email was transmitted directly fromone user to another computer. This required both computers to be online at the same time, a lainstant messenger. Today's email systems are based on a store-and-forward model. Email servers accept, forward, deliver and store messages. Users no longer need be online simultaneously andneed only connect briefly, typically to an email server, for as long as it takes to send or receivemessages.
An email message consists of two components, the message header , and the message body,which is the email's content. The message header contains control information, including,minimally, an originator's email address and one or more recipient addresses. Usually additionalinformation is added, such as a subject header field.
Originally a text-only communications medium, email was extended to carry multi-mediacontent attachments, a process standardized in RFC 2045 through 2049. Collectively, these RFCshave come to be called Multipurpose Internet Mail Extensions (MIME).
The history of modern, global Internet email services reaches back to the early ARPANET. Standards for encoding email messages were proposed as early as 1973 (RFC 561). Conversionfrom ARPANET to the Internet in the early 1980s produced the core of the current services. Anemail sent in the early 1970s looks quite similar to one sent on the Internet today.
Network-based email was initially exchanged on the ARPANET in extensions to the FileTransfer Protocol (FTP), but is now carried by the Simple Mail Transfer Protocol (SMTP), firstpublished as Internet standard 10 (RFC 821) in 1982. In the process of transporting emailmessages between systems, SMTP communicates delivery parameters using a message envelope separate from the message (header and body) itself.
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Spelling
There are several spelling variations that occasionally prove cause for surprisingly vehementdisagreement.[2][3]
email is the form required by IETF Requests for Comment and working groups[4] and increasinglyby style guides.[5] This spelling also appears in most dictionaries.[6][7][8][9][10][11]
e-mail is a form recommended by some prominent journalistic and technical style guides.[12][13]
According to Corpus of Contemporary American English data, this form appears most frequently
in edited, published American English writing.[14]
mail was the form used in the original RFC. The service is referred to as mail and a single piece
of electronic mail is called a message.[15][16][17]
eMail , capitalizing only the letter M, was common among ARPANET users and the early
developers of Unix, CMS, AppleLink, eWorld, AOL, GEnie, and Hotmail.[citation needed ]
EMail is a traditional form that has been used in RFCs for the "Author's Address",[16][17]
and is
expressly required "...for historical reasons..." .[18]
Origin
Electronic mail predates the inception of the Internet, and was in fact a crucial tool in creating it.
MIT first demonstrated the Compatible Time-Sharing System (CTSS) in 1961.[19] It allowedmultiple users to log into the IBM 7094[20] from remote dial-up terminals, and to store filesonline on disk. This new ability encouraged users to share information in new ways. Emailstarted in 1965 as a way for multiple users of a time-sharing mainframe computer tocommunicate. Among the first systems to have such a facility were SDC's Q32 and MIT's CTSS.
Host-based mail systems
The original email systems allowed communication only between users who logged into thesame host or "mainframe". This could be hundreds or even thousands of users within anorganization.
By 1966 (or earlier, it is possible that the SAGE system had something similar some timebefore), such systems allowed email between different organizations, so long as they rancompatible operating systems.
Examples include BITNET, IBM PROFS, Digital Equipment Corporation ALL-IN-1 and theoriginal Unix mail.
LAN-based mail systems
From the early 1980s, networked personal computers on LANs became increasingly important.Server-based systems similar to the earlier mainframe systems were developed. Again these
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systems initially allowed communication only between users logged into the same serverinfrastructure. Eventually these systems could also be linked between different organizations, aslong as they ran the same email system and proprietary protocol.
Examples include cc:Mail, Lantastic, WordPerfect Office, Microsoft Mail, Banyan VINES and
Lotus Notes - with various vendors supplying gateway software to link these incompatiblesystems.
Attempts at interoperability
Novell briefly championed the open MHS protocol but abandoned it after purchasing the non-
MHS WordPerfect Office (renamed Groupwise)
uucp was used as an open "glue" between differing mail systems
The Coloured Book protocols on UK academic networks until 1992
X.400 in the early 1990s was mandated for government use under GOSIP but almost
immediately abandoned by all but a few— in favour of Internet SMTP
From SNDMSG to MSG
In the early 1970s, Ray Tomlinson updated an existing utility called SNDMSG so that it couldcopy files over the network. Lawrence Roberts, the project manager for the ARPANETdevelopment, updated READMAIL and called the program RD. Barry Wessler then updated RD and called it NRD.[citation needed ]
Marty Yonke combined SNDMSG and NRD to include reading, sending, and a help system, andcalled the utility WRD. John Vittal then updated this version to include message forwarding andan Answer command to create replies with the correct address, and called it MSG. With inclusion
of these features, MSG is considered to be the first modern email program, from which manyother applications have descended.[21]
[edit ] The rise of ARPANET mail
The ARPANET computer network made a large contribution to the development of e-mail.There is one report that indicates experimental inter-system e-mail transfers began shortly afterits creation in 1969.[22] Ray Tomlinson is credited by some as having sent the first email,initiating the use of the "@" sign to separate the names of the user and the user's machine in1971, when he sent a message from one Digital Equipment Corporation DEC-10 computer toanother DEC-10. The two machines were placed next to each other.[23][24] The ARPANET
significantly increased the popularity of e-mail, and it became the killer app of the ARPANET.
Most other networks had their own email protocols and address formats; as the influence of theARPANET and later the Internet grew, central sites often hosted email gateways that passed mailbetween the Internet and these other networks. Internet email addressing is still complicated bythe need to handle mail destined for these older networks. Some well-known examples of thesewere UUCP (mostly Unix computers), BITNET (mostly IBM and VAX mainframes at
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universities), FidoNet (personal computers), DECNET (various networks) and CSNET aforerunner of NSFNet.
An example of an Internet email address that routed mail to a user at a UUCP host:
hubhost!middlehost!edgehost!user@uucpgateway.somedomain.example.com
This was necessary because in early years UUCP computers did not maintain (or consult serversfor) information about the location of all hosts they exchanged mail with, but rather only knewhow to communicate with a few network neighbors; email messages (and other data such asUsenet News) were passed along in a chain among hosts who had explicitly agreed to share datawith each other.
[edit] Operation overview
The diagram to the right shows a typical sequence of events[25] that takes place when Alice
composes a message using her mail user agent (MUA). She enters the e-mail address of hercorrespondent, and hits the "send" button.
1. Her MUA formats the message in e-mail format and uses the Simple Mail Transfer Protocol
(SMTP) to send the message to the local mail transfer agent (MTA), in this case smtp.a.org,
run by Alice's internet service provider (ISP).
2.
The MTA looks at the destination address provided in the SMTP protocol (not from the message
header), in this case [email protected]. An Internet e-mail address is a string of the form
localpart@exampledomain. The part before the @ sign is the local part of the address, often
the username of the recipient, and the part after the @ sign is a domain name or a fully
qualified domain name. The MTA resolves a domain name to determine the fully qualified
domain name of the mail exchange server in the Domain Name System (DNS).
3. The DNS server for the b.org domain, ns.b.org, responds with any MX records listing the
mail exchange servers for that domain, in this case mx.b.org, a server run by Bob's ISP.
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4. smtp.a.org sends the message to mx.b.org using SMTP, which delivers it to the mailbox of
the user bob.
5. Bob presses the "get mail" button in his MUA, which picks up the message using the Post Office
Protocol (POP3).
That sequence of events applies to the majority of e-mail users. However, there are manyalternative possibilities and complications to the e-mail system:
Alice or Bob may use a client connected to a corporate e-mail system, such as IBM Lotus Notes
or Microsoft Exchange. These systems often have their own internal e-mail format and their
clients typically communicate with the e-mail server using a vendor-specific, proprietary
protocol. The server sends or receives e-mail via the Internet through the product's Internet
mail gateway which also does any necessary reformatting. If Alice and Bob work for the same
company, the entire transaction may happen completely within a single corporate e-mail
system.
Alice may not have a MUA on her computer but instead may connect to a webmail service.
Alice's computer may run its own MTA, so avoiding the transfer at step 1.
Bob may pick up his e-mail in many ways, for example using the Internet Message Access
Protocol, by logging into mx.b.org and reading it directly, or by using a webmail service.
Domains usually have several mail exchange servers so that they can continue to accept mail
when the main mail exchange server is not available.
E-mail messages are not secure if e-mail encryption is not used correctly.
Many MTAs used to accept messages for any recipient on the Internet and do their best todeliver them. Such MTAs are called open mail relays. This was very important in the early daysof the Internet when network connections were unreliable. If an MTA couldn't reach thedestination, it could at least deliver it to a relay closer to the destination. The relay stood a betterchance of delivering the message at a later time. However, this mechanism proved to be
exploitable by people sending unsolicited bulk e-mail and as a consequence very few modernMTAs are open mail relays, and many MTAs don't accept messages from open mail relaysbecause such messages are very likely to be spam.
[edit] Message format
The Internet e-mail message format is defined in RFC 5322 and a series of RFCs, RFC 2045 through RFC 2049, collectively called, Multipurpose Internet Mail Extensions, or MIME .Although as of July 13, 2005, RFC 2822 is technically a proposed IETF standard and the MIMERFCs are draft IETF standards,[26] these documents are the standards for the format of Internet e-mail. Prior to the introduction of RFC 2822 in 2001, the format described by RFC 822 was thestandard for Internet e-mail for nearly 20 years; it is still the official IETF standard. The IETFreserved the numbers 5321 and 5322 for the updated versions of RFC 2821 (SMTP) and RFC2822, as it previously did with RFC 821 and RFC 822, honoring the extreme importance of thesetwo RFCs. RFC 822 was published in 1982 and based on the earlier RFC 733 (see [27]).
Internet e-mail messages consist of two major sections:
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Header — Structured into fields such as summary, sender, receiver, and other information about
the e-mail.
Body — The message itself as unstructured text; sometimes containing a signature block at the
end. This is exactly the same as the body of a regular letter.
The header is separated from the body by a blank line.
[edit ] Message header
Each message has exactly one header, which is structured into fields. Each field has a name anda value. RFC 5322 specifies the precise syntax.
Informally, each line of text in the header that begins with a printable character begins a separatefield. The field name starts in the first character of the line and ends before the separatorcharacter ":". The separator is then followed by the field value (the "body" of the field). Thevalue is continued onto subsequent lines if those lines have a space or tab as their first character.
Field names and values are restricted to 7-bit ASCII characters. Non-ASCII values may berepresented using MIME encoded words.
[edit] Header fields
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The message header should include at least the following fields:
From: The e-mail address, and optionally the name of the author(s). In many e-mail clients not
changeable except through changing account settings.
To: The e-mail address(es), and optionally name(s) of the message's recipient(s). Indicates
primary recipients (multiple allowed), for secondary recipients see Cc: and Bcc: below.
Subject : A brief summary of the topic of the message. Certain abbreviations are commonly used
in the subject, including "RE:" and "FW:".
Date: The local time and date when the message was written. Like the From: field, many email
clients fill this in automatically when sending. The recipient's client may then display the time in
the format and time zone local to him/her.
Message-ID: Also an automatically generated field; used to prevent multiple delivery and for
reference in In-Reply-To: (see below).
Note that the To: field is not necessarily related to the addresses to which the message isdelivered. The actual delivery list is supplied separately to the transport protocol, SMTP, whichmay or may not originally have been extracted from the header content. The "To:" field is similarto the addressing at the top of a conventional letter which is delivered according to the addresson the outer envelope. Also note that the "From:" field does not have to be the real sender of thee-mail message. One reason is that it is very easy to fake the "From:" field and let a message
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seem to be from any mail address. It is possible to digitally sign e-mail, which is much harder tofake, but such signatures require extra programming and often external programs to verify. SomeISPs do not relay e-mail claiming to come from a domain not hosted by them, but very few (if any) check to make sure that the person or even e-mail address named in the "From:" field is theone associated with the connection. Some ISPs apply e-mail authentication systems to e-mail
being sent through their MTA to allow other MTAs to detect forged spam that might appear tocome from them.
RFC 3864 describes registration procedures for message header fields at the IANA; it providesfor permanent and provisional message header field names, including also fields defined forMIME, netnews, and http, and referencing relevant RFCs. Common header fields for emailinclude:
Bcc: Blind Carbon Copy; addresses added to the SMTP delivery list but not (usually) listed in the
message data, remaining invisible to other recipients.
Cc: Carbon copy; Many e-mail clients will mark e-mail in your inbox differently depending on
whether you are in the To: or Cc: list.
Content-Type: Information about how the message is to be displayed, usually a MIME type.
In-Reply-To: Message-ID of the message that this is a reply to. Used to link related messages
together.
Precedence: commonly with values "bulk", "junk", or "list"; used to indicate that automated
"vacation" or "out of office" responses should not be returned for this mail, e.g. to prevent
vacation notices from being sent to all other subscribers of a mailinglist. Sendmail uses this
header to affect prioritization of queued e-mail, with "Precedence: special-delivery" messages
delivered sooner. With modern high-bandwidth networks delivery priority is less of an issue
than it once was. Microsoft Exchange respects a fine-grained automatic response suppression
mechanism, the X-Auto-Response-Suppress header.[28]
Received: Tracking information generated by mail servers that have previously handled a
message, in reverse order (last handler first). References: Message-ID of the message that this is a reply to, and the message-id of the
message the previous was reply a reply to, etc.
Reply-To: Address that should be used to reply to the message.
Sender: Address of the actual sender acting on behalf of the author listed in the From: field
(secretary, list manager, etc.).
[edit ] Message body
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[edit] Content encoding
E-mail was originally designed for 7-bit ASCII.[29] Much e-mail software is 8-bit clean but mustassume it will communicate with 7-bit servers and mail readers. The MIME standard introducedcharacter set specifiers and two content transfer encodings to enable transmission of non-ASCII
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data: quoted printable for mostly 7 bit content with a few characters outside that range andbase64 for arbitrary binary data. The 8BITMIME extension was introduced to allow transmissionof mail without the need for these encodings but many mail transport agents still do not supportit fully. In some countries, several encoding schemes coexist; as the result, by default, themessage in a non-Latin alphabet language appears in non-readable form (the only exception is
coincidence, when the sender and receiver use the same encoding scheme). Therefore, forinternational character sets, Unicode is growing in popularity.
[edit] Plain text and HTML
Most modern graphic e-mail clients allow the use of either plain text or HTML for the messagebody at the option of the user. HTML e-mail messages often include an automatically-generatedplain text copy as well, for compatibility reasons.
Advantages of HTML include the ability to include in-line links and images, set apart previousmessages in block quotes, wrap naturally on any display, use emphasis such as underlines and
italics, and change font styles. Disadvantages include the increased size of the email, privacyconcerns about web bugs, abuse of HTML email as a vector for phishing attacks and the spreadof malicious software.[30]
Some web based Mailing lists recommend that all posts be made in plain-text[31][32] for all theabove reasons, but also because they have a significant number of readers using text-based e-mail clients such as Mutt.
Some Microsoft e-mail clients allow rich formatting using RTF, but unless the recipient isguaranteed to have a compatible e-mail client this should be avoided.[33]
In order to ensure that HTML sent in an email is rendered properly by the recipient's clientsoftware, an additional header must be specified when sending: "Content-type: text/html". Mostemail programs send this header automatically.
.
Messages are exchanged between hosts using the Simple Mail Transfer Protocol with softwareprograms called mail transfer agents. Users can retrieve their messages from servers usingstandard protocols such as POP or IMAP, or, as is more likely in a large corporate environment,with a proprietary protocol specific to Lotus Notes or Microsoft Exchange Servers. Webmailinterfaces allow users to access their mail with any standard web browser, from any computer,rather than relying on an e-mail client.
Mail can be stored on the client, on the server side, or in both places. Standard formats formailboxes include Maildir and mbox. Several prominent e-mail clients use their own proprietaryformat and require conversion software to transfer e-mail between them.
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Accepting a message obliges an MTA to deliver it, and when a message cannot be delivered, thatMTA must send a bounce message back to the sender, indicating the problem.
[edit ] Filename extensions
Upon reception of e-mail messages, e-mail client applications save message in operating systemfiles in the file-system. Some clients save individual messages as separate files, while others usevarious database formats, often proprietary, for collective storage. A historical standard of storage is the mbox format. The specific format used is often indicated by special filenameextensions:
eml
Used by many e-mail clients including Microsoft Outlook Express, Windows Mail and Mozilla
Thunderbird.[34] The files are plain text in MIME format, containing the e-mail header as well as
the message contents and attachments in one or more of several formats.
emlx
Used by Apple Mail.
msg
Used by Microsoft Office Outlook and OfficeLogic Groupware.
mbx
Used by Opera Mail, KMail, and Apple Mail based on the mbox format.
Some applications (like Apple Mail) leave attachments encoded in messages for searching whilealso saving separate copies of the attachments. Others separate attachments from messages andsave them in a specific directory.
[edit ] URI scheme mailto:
The URI scheme, as registered with the IANA, defines the mailto: scheme for SMTP emailaddresses. Though its use is not strictly defined, URLs of this form are intended to be used toopen the new message window of the user's mail client when the URL is activated, with theaddress as defined by the URL in the To: field.[35]
[edit] Use
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[edit ] In society
There are numerous ways in which people have changed the way they communicate in the last50 years; e-mail is certainly one of them. Traditionally, social interaction in the local communitywas the basis for communication – face to face. Yet, today face-to-face meetings are no longer
the primary way to communicate as one can use a landline telephone, mobile phones, fax services, or any number of the computer mediated communications such as e-mail.
Research has shown that people actively use e-mail to maintain core social networks, particularlywhen others live at a distance. However, contradictory to previous research, the results suggestthat increases in Internet usage are associated with decreases in other modes of communication,with proficiency of Internet and e-mail use serving as a mediating factor in this relationship.[36] With the introduction of chat messengers and video conference, there are more ways tocommunicate.
[edit] Flaming
Flaming occurs when a person sends a message with angry or antagonistic content. Flaming isassumed to be more common today because of the ease and impersonality of e-mailcommunications: confrontations in person or via telephone require direct interaction, wheresocial norms encourage civility, whereas typing a message to another person is an indirectinteraction, so civility may be forgotten.[citation needed ] Flaming is generally looked down upon byInternet communities as it is considered rude and non-productive.
E-mail bankruptcy
Also known as "e-mail fatigue", e-mail bankruptcy is when a user ignores a large number of e-
mail messages after falling behind in reading and answering them. The reason for falling behindis often due to information overload and a general sense there is so much information that it isnot possible to read it all. As a solution, people occasionally send a boilerplate messageexplaining that the e-mail inbox is being cleared out. Stanford University law professorLawrence Lessig is credited with coining this term, but he may only have popularized it.[37]
In business
E-mail was widely accepted by the business community as the first broad electronic
communication medium and was the first ‘e-revolution’ in business communication. E-mail
is very simple to understand and like postal mail, e-mail solves two basic problems of
communication: logistics and synchronization (see below).
LAN based email is also an emerging form of usage for business. It not only allows the businessuser to download mail when offline, it also provides the small business user to have multipleusers e-mail ID's with just one e-mail connection.
Pros
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The problem of logistics: Much of the business world relies upon communications between
people who are not physically in the same building, area or even country; setting up and
attending an in-person meeting, telephone call, or conference call can be inconvenient, time-
consuming, and costly. E-mail provides a way to exchange information between two or more
people with no set-up costs and that is generally far less expensive than physical meetings or
phone calls.
The problem of synchronisation: With real time communication by meetings or phone calls,
participants have to work on the same schedule, and each participant must spend the same
amount of time in the meeting or call. E-mail allows asynchrony: each participant may control
their schedule independently.
Cons
Most business workers today spend from one to two hours of their working day on e-mail:reading, ordering, sorting, ‘re-contextualizing’ fragmented information, and writing e-mail.[38]
The use of e-mail is increasing due to increasing levels of globalisation — labour division andoutsourcing amongst other things. E-mail can lead to some well-known problems:
Loss of context : which means that the context is lost forever; there is no way to get the text
back. Information in context (as in a newspaper) is much easier and faster to understand than
unedited and sometimes unrelated fragments of information. Communicating in context can
only be achieved when both parties have a full understanding of the context and issue in
question.
Information overload : E-mail is a push technology—the sender controls who receives the
information. Convenient availability of mailing lists and use of "copy all" can lead to people
receiving unwanted or irrelevant information of no use to them.
Inconsistency : E-mail can duplicate information. This can be a problem when a large team isworking on documents and information while not in constant contact with the other members
of their team.
Despite these disadvantages, e-mail has become the most widely used medium of communication within the business world.
Attachment size limitation
Email messages may have one or more attachments. Attachments serve the purpose of deliveringbinary or text files of unspecified size. In principle there is no technical intrinsic restriction in the
SMTP protocol limiting the size or number of attachments. In practice, however, email serviceproviders implement various limitations on the permissible size of files or the size of an entiremessage.
Furthermore, due to technical reasons, often a small attachment can increase in size whensent,[39] which can be confusing to senders when trying to assess whether they can or cannot senda file by e-mail, and this can result in their message being rejected.
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As larger and larger file sizes are being created and traded, many users are either forced toupload and download their files using an FTP server, or more popularly, use online file sharingfacilities or services, usually over web-friendly HTTP, in order to send and receive them.
[edit ] Information overload
A December 2007 New York Times blog post described information overload as "a $650 BillionDrag on the Economy",[40] and the New York Times reported in April 2008 that "E-MAIL hasbecome the bane of some peo ple’s professional lives" due to information overload, yet "none of the current wave of high-profile Internet start-ups focused on e-mail really eliminates theproblem of e-mail overload because none helps us prepare replies".[41]
Technology investors reflect similar concerns.[42]
The email services are trying to provide maximum email inbox space to save the large sizedocuments(attachments).
[edit ] Spamming and computer viruses
The usefulness of e-mail is being threatened by four phenomena: e-mail bombardment, spamming, phishing, and e-mail worms.
Spamming is unsolicited commercial (or bulk) e-mail. Because of the very low cost of sending e-mail, spammers can send hundreds of millions of e-mail messages each day over an inexpensiveInternet connection. Hundreds of active spammers sending this volume of mail results ininformation overload for many computer users who receive voluminous unsolicited e-mail eachday.[43][44]
E-mail worms use e-mail as a way of replicating themselves into vulnerable computers.Although the first e-mail worm affected UNIX computers, the problem is most common todayon the more popular Microsoft Windows operating system.
The combination of spam and worm programs results in users receiving a constant drizzle of junk e-mail, which reduces the usefulness of e-mail as a practical tool.
A number of anti-spam techniques mitigate the impact of spam. In the United States, U.S.Congress has also passed a law, the Can Spam Act of 2003, attempting to regulate such e-mail.Australia also has very strict spam laws restricting the sending of spam from an Australian
ISP,[45]
but its impact has been minimal since most spam comes from regimes that seem reluctantto regulate the sending of spam.[citation needed ]
[edit ] E-mail spoofing
Main article: E-mail spoofing
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E-mail spoofing occurs when the header information of an email is altered to make the messageappear to come from a known or trusted source. It is often used as a ruse to collect personalinformation.
[edit ] E-mail bombing
E-mail bombing is the intentional sending of large volumes of messages to a target address. Theoverloading of the target email address can render it unusable and can even cause the mail serverto crash.
E-mail privacy, without some security precautions, can be compromised because:
e-mail messages are generally not encrypted.
e-mail messages have to go through intermediate computers before reaching their destination,
meaning it is relatively easy for others to intercept and read messages.
many Internet Service Providers (ISP) store copies of e-mail messages on their mail servers
before they are delivered. The backups of these can remain for up to several months on their
server, despite deletion from the mailbox.
the "Received:"-fields and other information in the e-mail can often identify the sender,
preventing anonymous communication.
There are cryptography applications that can serve as a remedy to one or more of the above. Forexample, Virtual Private Networks or the Tor anonymity network can be used to encrypt trafficfrom the user machine to a safer network while GPG, PGP, SMEmail,[46] or S/MIME can be usedfor end-to-end message encryption, and SMTP STARTTLS or SMTP over Transport LayerSecurity / Secure Sockets Layer can be used to encrypt communications for a single mail hopbetween the SMTP client and the SMTP server.
Additionally, many mail user agents do not protect logins and passwords, making them easy tointercept by an attacker. Encrypted authentication schemes such as SASL prevent this.
Finally, attached files share many of the same hazards as those found in peer-to-peer filesharing. Attached files may contain trojans or viruses.
[edit ] Tracking of sent mail
The original SMTP mail service provides limited mechanisms for tracking a transmittedmessage, and none for verifying that it has been delivered or read. It requires that each mailserver must either deliver it onward or return a failure notice (bounce message), but bothsoftware bugs and system failures can cause messages to be lost. To remedy this, the IETF introduced Delivery Status Notifications (delivery receipts) and Message DispositionNotifications (return receipts); however, these are not universally deployed in production.
Many ISPs now deliberately disable non-delivery report (NDRs) and delivery receipts due to theactivities of spammers:
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Delivery Reports can be used to verify whether an address exists and so is available to be
spammed
If the spammer uses a forged sender Email address (E-mail spoofing), then the innocent E-mail
address that was used can be flooded with NDRs from the many invalid E-mail addresses the
spammer may have attempted to mail. These NDRs then constitute spam from the ISP to the
innocent user
There are a number of systems that allow the sender to see if messages have beenopened.[47][48][49]
[edit] US Government
The US Government has been involved in e-mail in several different ways.
Starting in 1977, the US Postal Service (USPS) recognized that electronic mail and electronictransactions posed a significant threat to First Class mail volumes and revenue. Therefore, the
USPS initiated an experimental e-mail service known as E-COM. Electronic messages weretransmitted to a post office, printed out, and delivered as hard copy. To take advantage of theservice, an individual had to transmit at least 200 messages. The delivery time of the messageswas the same as First Class mail and cost 26 cents. Both the Postal Regulatory Commission andthe Federal Communications Commission opposed E-COM. The FCC concluded that E-COMconstituted common carriage under its jurisdiction and the USPS would have to file a tariff .[50] Three years after initiating the service, USPS canceled E-COM and attempted to sell itoff .[51][52][53][54][55][56][57]
The early ARPANET dealt with multiple e-mail clients that had various, and at timesincompatible, formats. For example, in the system Multics, the "@" sign meant "kill line" and
anything after the "@" sign was ignored.[58]
The Department of Defense DARPA desired to haveuniformity and interoperability for e-mail and therefore funded efforts to drive towards unifiedinter-operable standards. This led to David Crocker, John Vittal, Kenneth Pogran, and AustinHenderson publishing RFC 733, "Standard for the Format of ARPA Network Text Message"(November 21, 1977), which was apparently not effective. In 1979, a meeting was held at BBNto resolve incompatibility issues. Jon Postel recounted the meeting in RFC 808, "Summary of Computer Mail Services Meeting Held at BBN on 10 January 1979" (March 1, 1982), whichincludes an appendix listing the varying e-mail systems at the time. This, in turn, lead to therelease of David Crocker's RFC 822, "Standard for the Format of ARPA Internet Text Messages"(August 13, 1982).[59]
The National Science Foundation took over operations of the ARPANET and Internet from theDepartment of Defense, and initiated NSFNet, a new backbone for the network. A part of theNSFNet AUP forbade commercial traffic.[60] In 1988, Vint Cerf arranged for an interconnectionof MCI Mail with NSFNET on an experimental basis. The following year Compuserve e-mailinterconnected with NSFNET. Within a few years the commercial traffic restriction wasremoved from NSFNETs AUP, and NSFNET was privatised.
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In the late 1990s, the Federal Trade Commission grew concerned with fraud transpiring in e-mail, and initiated a series of procedures on spam, fraud, and phishing.[61] In 2004, FTC jurisdiction over spam was codified into law in the form of the CAN SPAM Act.[62] Several otherUS Federal Agencies have also exercised jurisdiction including the Department of Justice andthe Secret Service.
