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Wikibook about Computer Mediated Communication (CMC). Created using Wikipedia Creative Commons licence. http://creativecommons.org/licenses/by-sa/3.0/ Created for my students on ITEC10031 - The Internet, Computers & Society module at NTU.
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1. Computer MediatedCommunicationWikibook ITEC30011 PDF
generated using the open source mwlib toolkit. See
http://code.pediapress.com/ for more information. PDF generated at:
Mon, 16 May 2011 13:54:21 UTC
2. ContentsArticles Computer-mediated communication 1 Email 4
Instant messaging 19 Social networking service 28 Opportunity cost
41 Acceptable use policy 43References Article Sources and
Contributors 46 Image Sources, Licenses and Contributors 49Article
Licenses License 50
3. Computer-mediated communication 1 Computer-mediated
communication Computer-mediated communication (CMC) is defined as
any communicative transaction that occurs through the use of two or
more networked computers.[1] While the term has traditionally
referred to those communications that occur via computer-mediated
formats (e.g., instant messages, e-mails, chat rooms), it has also
been applied to other forms of text-based interaction such as text
messaging.[2] Research on CMC focuses largely on the social effects
of different computer-supported communication technologies. Many
recent studies involve Internet-based social networking supported
by social software. Scope of the field Scholars from a variety of
fields study phenomena that can be described under the umbrella
term of CMC (see also Internet studies). For example, many take a
sociopsychological approach to CMC by examining how humans use
"computers" (or digital media) to manage interpersonal interaction,
form impressions and form and maintain relationships.[3] [4] These
studies have often focused on the differences between online and
offline interactions, though contemporary research is moving
towards the view that CMC should be studied as embedded in everyday
life .[5] Another branch of CMC research examines the use of
paralinguistic features such as emoticons, pragmatic rules such as
turn-taking[6] and the sequential analysis and organization of
talk,[7] [8] and the various sociolects, styles, registers or sets
of terminology specific to these environments (see Leet). The study
of language in these contexts is typically based on text-based
forms of CMC, and is sometimes referred to as "computer-mediated
discourse analysis".[9] The way humans communicate in professional,
social, and educational settings varies widely, depending upon not
only the environment but also the method of communication in which
the communication occurs, which in this case is through computers
or other information and computer technologies (ICTs). The study of
communication to achieve collaborationcommon work productsis termed
computer-supported collaboration and includes only some of the
concerns of other forms of CMC research. Popular forms of CMC
include e-mail, video, audio or text chat (text conferencing
including "instant messaging"), bulletin boards, list-servs and
MMOs.[10] These settings are changing rapidly with the development
of new technologies. Weblogs (blogs) have also become popular, and
the exchange of RSS data has better enabled users to each "become
their own publisher". Characteristics Communication occurring
within a computer-mediated format has an effect on many different
aspects of an interaction. Some of these that have received
attention in the scholarly literature include impression formation,
deception, group dynamics, disinhibition and especially
relationship formation. CMC is examined and compared to other
communication media through a number of aspects thought to be
universal to all forms of communication, including (but not limited
to) synchronicity, persistence or "recordability", and anonymity.
The association of these aspects with different forms of
communication varies widely. For example, instant messaging is
intrinsically synchronous but not persistent, since one loses all
the content when one closes the dialog box unless one has a message
log set up or has manually copy-pasted the conversation. E-mail and
message boards, on the other hand, are low in synchronicity since
response time varies, but high in persistence since messages sent
and received are saved. Properties that separate CMC from other
media also include transience, its multimodal nature, and its
relative lack of governing codes of conduct.[11] CMC is able to
overcome physical and social limitations of other forms of
communication and therefore allow the interaction of people who are
not physically sharing the same space.
4. Computer-mediated communication 2 Anonymity and in part
privacy and security depends more on the context and particular
program being used or web page being visited. However, most
researchers in the field acknowledge the importance of considering
the psychological and social implications of these factors
alongside the technical "limitations". Types CMC can be divided
into synchronous and asynchronous modes. In synchronous
communications all participants are online at the same time (e.g.
IRC), while asynchronous communications occurs with time
constraints. (e.g e mail) Language learning CMC is widely discussed
in language learning because CMC provides opportunities for
language learners to practice their language.[12] For example,
Warschauer[13] conducted several case studies on using email or
discussion boards in different language classes. Warschauer[14]
claimed that information and communications technology bridge the
historic divide between speech and writing. Thus, considerable
concern has arisen over the reading and writing research in L2 due
to the booming of Internet. References [1] McQuail, Denis. (2005).
Mcquails Mass Communication Theory. 5th ed. London: SAGE
Publications. [2] Thurlow, C., Lengel, L. & Tomic, A. (2004).
Computer mediated communication: Social interaction and the
internet. London: Sage. [3] Walther, J. B. (1996).
Computer-mediated communication: Impersonal, interpersonal, and
hyperpersonal interaction. Communication Research, 23, 3-43. [4]
Walther, J. B., & Burgoon, J. K. (1992). Relational
communication in computer-mediated interaction. Human Communication
Research, 19, 50-88. [5] Haythornthwaite, C. and Wellman, B.
(2002). The Internet in everyday life: An introduction. In B.
Wellman and C. Haythornthwaite (Eds.), The Internet in Everyday
Life (pp. 3-41). Oxford: Blackwell. [6] Garcia, A. C., &
Jacobs, J. B. (1999). The eyes of the beholder: Understanding the
turn-taking system in quasi-synchronous computer-mediated
communication. Research on Language & Social Interaction, 32,
337-367. [7] Herring, S. (1999). Interactional coherence in CMC.
Journal of Computer-Mediated Communication, 4(4). http:/ / jcmc.
indiana. edu/ vol4/ issue4/ herring. html [8] Markman, K. M.
(2006). Computer-mediated conversation: The organization of talk in
chat-based virtual team meetings. Dissertation Abstracts
International, 67 (12A), 4388. (UMI No. 3244348) [9] Herring, S. C.
(2004). Computer-mediated discourse analysis: An approach to
researching online behavior. In: S. A. Barab, R. Kling, and J. H.
Gray (Eds.), Designing for Virtual Communities in the Service of
Learning (pp. 338-376). New York: Cambridge University Press. [10]
Bishop, J. (2009). Enhancing the understanding of genres of
web-based communities: The role of the ecological cognition
framework. International Journal of Web-Based Communities, 5(1),
4-17. Available online (http:/ / crocels. com/ index. php?q=node/
6) [11] McQuail, Denis. (2005). Mcquails Mass Communication Theory.
5th ed. London: SAGE Publications. [12] Abrams, Z. (2006). From
Theory to Practice: Intracultural CMC in the L2 Classroom. book
chapter, forthcoming in Ducate, Lara & Nike Arnold (Eds.)
Calling on CALL: From Theory and Research to New Directions in
Foreign Language Teaching. [13] Warschauer, M. (1998). Electronic
literacies: Language, culture and power in online education.
Mahwah, NJ: Lawrence Erlbaum Associates. [14] Warschauer, M.
(2006). Laptops and literacy: learning in the wireless classroom:
Teachers College, Columbia University. Further reading Ahern, T.C.,
Peck, K., & Laycock, M. (1992). The effects of teacher
discourse in computer-mediated discussion. Journal of Educational
Computing Research, 8(3), 291-309. Angeli, C., Valanides, N., &
Bonk, C.J. (2003). Communication in a web-based conferencing
system: The quality of computer-mediated interactions. British
Journal of Educational Technology, 34(1), 31-43. Bannan-Ritland, B.
(2002). Computer-mediated communication, elearning, and
interactivity: A review of the research. Quarterly Review of
Distance Education, 3(2), 161-180. Christopher, M.M., Thomas, J.A.,
and Tallent-Runnels, M.K. (2004). Raising the Bar: Encouraging high
level thinking in online discussion forums. Roeper Review, 26(3),
166-171.
5. Computer-mediated communication 3 Cooper, M.M., & Selfe,
C.L. (1990). Computer conferences and learning: Authority,
resistance, and internally persuasive discourse. College English,
52(8), 847-869. Forman, E.A. (2000). Knowledge building in
discourse communities. Human Development, 43(6), 364-368. Gabriel,
M.A. (2004). Learning together: Exploring group interactions
online. Journal of Distance Education, 19(1), 54-72. Gilbert, K.G.,
& Dabbagh, N. (2005). How to structure online discussions for
meaningful discourse: a case study. British Journal of Educational
Technology, 36(1), 5-18. Gunawardena, C.H., Nolla, A.C., Wilson,
P.L., Lopez-Isias, Jr. et al. (2001). A cross-cultural study of
group process and development in online conferences. Distance
Education, 22(1), 85-122. Hara, N., Bonk, C.J., & Angeli, C.
(2000). Content analysis of online discussion in an applied
educational psychology course. Instructional Science, 28, 115-152.
Hewitt, J. (2001). Beyond threaded discourse. International Journal
of Educational Telecommunications, 7(3), 207-221. Hewitt, J.
(2003). How habitual online practices affect the development of
asynchronous discussion threads. Journal of Educational Computing
Research, 28(1), 31-45. Javela, S., Bonk, C.J., & Sirpalethti,
S.L. (1999). A theoretical analysis of social interactions in
computer-based learning environments: Evidence for reciprocal
understandings. Journal of Educational Computing Research, 21(3),
363-388. Jones, G., & Schieffelin, B. (2009). Enquoting Voices,
Accomplishing Talk: Uses of Be+Like in Instant Messaging. Language
& Communication, 29(1), 77-113. Jones, G., & Schieffelin,
B. (2009). Talking Text and Talking Back: "My BFF Jill" from Boob
Tube to YouTube. Journal of Computer-Mediated Communication, 14(4),
1050 - 1079. Kalman, Y. M. and Rafaeli, S. (2007-05-23). Modulating
Synchronicity in Computer-Mediated Communication. Paper presented
at the annual meeting of the International Communication
Association, TBA, San Francisco, CA Online . 2010-01-24 from
http://www.allacademic.com/meta/p170694_index.html Kirk, J.J.,
& Orr, R.L. (2003). A primer on the effective use of threaded
discussion forums. ERIC document. Lapadat, J.C. (2003). Teachers in
an online seminar talking about talk: Classroom discourse and
school change. Language and Education, 17(1), 21-41. Leinonen, P.,
Jarvela, S., & Lipponen, L. (2003). Individual students
interpretations of their contribution to the computer-mediated
discussions. Journal of Interactive Learning Research, 14(1),
99-122. Lin, L. (2008). An online learning model to facilitate
learners rights to education. Journal of Asynchronous Learning
Networks (JALN), 12(1), pp.127143. [Special issue distributed by
Sloan-C JALN in collaboration with five other international
journals: http://www.distanceandaccesstoeducation.org/] Lin, L.,
Cranton, P. & Bridglall, B. (2005). Psychological type and
asynchronous written dialogue in adult learning. Teachers College
Record, 107(8), 1788-1813. MackNnight, C.B. (2000). Teaching
critical thinking through online discussions. Educause Quarterly,
4, 38-41. Poole, D.M. (2000). Student participation in a
discussion-oriented online course: A case study. Journal of
Research on Computing in Education, 33(2), 162-176. Schrire, S.
(2003). A model for evaluating the process of learning in
asynchronous computer conferencing. Journal of Instructional
Delivery Systems, 17(1), 6-12. Vonderwell, S. (2002). An
examination of asynchronous communication experiences and
perspectives of students in an online course: A case study. The
Internet and Higher Education, 6, 77-90.
6. Computer-mediated communication 4 Wade, S.E., & Fauske,
J.R. (2004). Dialogue online: Prospective teachers discourse
strategies in computer-mediated discussions. Reading Research
Quarterly, 39(2), 134-160. Wu, D., & Hiltz, S.R. (2004).
Predicting learning from asynchronous online discussions. Journal
of Asynchronous Learning Networks, 8(2), 139-152. Email Electronic
mail, commonly called email or e-mail, is a method of exchanging
digital messages from an author to one or more recipients. Modern
email operates across the Internet or other computer networks. Some
early email systems required that the author and the recipient both
be online at the same time, a la instant messaging. Todays email
systems are based on a store-and-forward model. Email servers
accept, forward, deliver and store messages. Neither the users nor
their computers are required to be online simultaneously; they need
connect only briefly, typically to an email server, for as long as
it takes to send or receive messages. An email message consists of
three components, the message envelope, the The at sign, a part of
every SMTP email [1] message header, and the message body. The
message header contains control address information, including,
minimally, an originators email address and one or more recipient
addresses. Usually descriptive information is also added, such as a
subject header field and a message submission date/time stamp.
Originally a text-only (7-bit ASCII and others) communications
medium, email was extended to carry multi-media content
attachments, a process standardized in RFC 2045 through 2049.
Collectively, these RFCs have 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). Conversion from ARPANET to the Internet in the
early 1980s produced the core of the current services. An email
sent in the early 1970s looks quite similar to a basic text message
sent on the Internet today. Network-based email was initially
exchanged on the ARPANET in extensions to the File Transfer
Protocol (FTP), but is now carried by the Simple Mail Transfer
Protocol (SMTP), first published as Internet standard 10 (RFC 821)
in 1982. In the process of transporting email messages between
systems, SMTP communicates delivery parameters using a message
envelope separate from the message (header and body) itself.
Spelling There are several spelling options that occasionally prove
cause for surprisingly vehement disagreement.[2] [3] email is the
form required by IETF Requests for Comment and working groups[4]
and increasingly by style guides.[5] [6] [7] This spelling also
appears in most dictionaries.[8] [9] [10] [11] [12] [13] e-mail is
a form previously recommended by some prominent journalistic and
technical style guides. 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.
7. Email 5 EMail is a traditional form that has been used in
RFCs for the "Authors Address",[16] [17] and is expressly required
"...for historical reasons...".[18] E-mail, capitalizing the
initial letter E in the same way as A-bomb, H-bomb, X-ray, T-shirt,
and similar shortenings.[19] Origin Electronic mail predates the
inception of the Internet, and was in fact a crucial tool in
creating it.[20] MIT first demonstrated the Compatible Time-Sharing
System (CTSS) in 1961.[21] It allowed multiple users to log into
the IBM 7094[22] from remote dial-up terminals, and to store files
online on disk. This new ability encouraged users to share
information in new ways. Email started in 1965 as a way for
multiple users of a time-sharing mainframe computer to communicate.
Among the first systems to have such a facility were SDCs Q32 and
MITs CTSS. Host-based mail systems The original email systems
allowed communication only between users who logged into the same
host or "mainframe". This could be hundreds or even thousands of
users within an organization. Examples include MITs 1965 CTSS
MAIL,[23] Larry Breeds 1972 APL Mailbox (which was used by the 1976
Carter/Mondale presidential campaign),[24] [25] the original 1972
Unix mail program,[26] [27] IBMs 1981 PROFS, and Digital Equipment
Corporations 1982 ALL-IN-1,.[28] Homogeneous email networks and
LAN-based mail systems Many early peer-to-peer email networking
only worked among computers running the same OS or program.
Examples include: By 1966 or earlier, it is possible that the SAGE
system had a limited form of email 1978s uucp[29] and 1980s Usenet
provided Unix-to-Unix copying of email, files, and shared fora over
dialup modems or leased lines BITNET in 1981 allowed IBM mainframes
to communicate email over leased lines. FidoNets 1984 application
software for IBM PCs running DOS transferred email and shared
bulletin board postings by dialup modem In the early 1980s,
networked personal computers on LANs became increasingly important.
Server-based systems similar to the earlier mainframe systems were
developed. Again these systems initially allowed communication only
between users logged into the same server infrastructure.
Eventually these systems could also be linked between different
organizations, as long 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
incompatible systems.
8. Email 6 Attempts at interoperability Early interoperability
among independent systems included: ARPANET, the forerunner of
todays Internet, defined the first protocols for dissimilar
computers to exchange email uucp implementations for non-Unix
systems were used as an open "glue" between differing mail systems,
primarily over dialup telephones CSNet used dial-up telephone
access to link additional sites to the ARPANET and then Internet
Later efforts at interoperability standardization included: Novell
briefly championed the open MHS protocol but abandoned it after
purchasing the non-MHS WordPerfect Office (renamed Groupwise) The
Coloured Book protocols on UK academic networks until 1992 X.400 in
the 1980s and early 1990s was promoted by major vendors and
mandated for government use under GOSIP but abandoned by all but a
few in favor of Internet SMTP by the mid-1990s. From SNDMSG to MSG
In the early 1970s, Ray Tomlinson updated an existing utility
called SNDMSG so that it could copy messages (as files) over the
network. Lawrence Roberts, the project manager for the ARPANET
development, took the idea of READMAIL, which dumped all "recent"
messages onto the users terminal, and wrote a program for TENEX in
TECO macros called RD which permitted accessing individual
messages.[30] Barry Wessler then updated RD and called it NRD.
Marty Yonke combined rewrote NRD to include reading, access to
SNMSG for sending, and a help system, and called the utility WRD
which was later known as BANANARD. John Vittal then updated this
version to include message forwarding and an Answer command that
automatically created a reply message with the correct address(es).
This was the first email "reply" command; the system was called
MSG. With inclusion of these features, MSG is considered to be the
first integrated modern email program, from which many other
applications have descended.[30] The rise of ARPANET mail The
ARPANET computer network made a large contribution to the
development of email. There is one report that indicates
experimental inter-system email transfers began shortly after its
creation in 1969.[23] Ray Tomlinson is generally credited as having
sent the first email across a network, initiating the use of the
"@" sign to separate the names of the user and the users machine in
1971, when he sent a message from one Digital Equipment Corporation
DEC-10 computer to another DEC-10. The two machines were placed
next to each other.[31] [32] Tomlinsons work was quickly adopted
across the ARPANET, which significantly increased the popularity of
email. For many years, email was the killer app of the ARPANET and
then the Internet. Most other networks had their own email
protocols and address formats; as the influence of the ARPANET and
later the Internet grew, central sites often hosted email gateways
that passed mail between the Internet and these other networks.
Internet email addressing is still complicated by the need to
handle mail destined for these older networks. Some well-known
examples of these were UUCP (mostly Unix computers), BITNET (mostly
IBM and VAX mainframes at universities), FidoNet (personal
computers), DECNET (various networks) and CSNET a forerunner 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
9. Email 7 This was necessary because in early years UUCP
computers did not maintain (or consult servers for) information
about the location of all hosts they exchanged mail with, but
rather only knew how to communicate with a few network neighbors;
email messages (and other data such as Usenet News) were passed
along in a chain among hosts who had explicitly agreed to share
data with each other. Operation overview The diagram to the right
shows a typical sequence of events[33] that takes place when Alice
composes a message using her mail user agent (MUA). She enters the
email address of her correspondent, and hits the "send" button. 1.
Her MUA formats the message in email format and uses the Submission
Protocol (a profile of the Simple Mail Transfer Protocol (SMTP),
see RFC 4409) to send the message to the local mail submission
agent (MSA), in this case smtp.a.org, run by Alices internet
service provider (ISP). 2. The MSA looks at the destination address
provided in the SMTP protocol (not from the message header), in
this case [email protected]. An Internet email 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 MSA 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 message transfer
agent (MTA) server run by Bobs ISP. 4. smtp.a.org sends the message
to mx.b.org using SMTP. This server may need to forward the message
to other MTAs before the message reaches the final message delivery
agent (MDA). 1. The MDA delivers it to the mailbox of the user bob.
2. Bob presses the "get mail" button in his MUA, which picks up the
message using either the Post Office Protocol (POP3) or the
Internet Message Access Protocol (IMAP4). That sequence of events
applies to the majority of email users. However, there are many
alternative possibilities and complications to the email system:
Alice or Bob may use a client connected to a corporate email
system, such as IBM Lotus Notes or Microsoft Exchange. These
systems often have their own internal email format and their
clients typically communicate with the email server using a
vendor-specific, proprietary protocol. The server sends or receives
email via the Internet
10. Email 8 through the products 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 email system. Alice may not have a MUA on her
computer but instead may connect to a webmail service. Alices
computer may run its own MTA, so avoiding the transfer at step 1.
Bob may pick up his email in many ways, for example 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. Email messages are not secure if email encryption is not
used correctly. Many MTAs used to accept messages for any recipient
on the Internet and do their best to deliver them. Such MTAs are
called open mail relays. This was very important in the early days
of the Internet when network connections were unreliable. If an MTA
couldnt reach the destination, it could at least deliver it to a
relay closer to the destination. The relay stood a better chance of
delivering the message at a later time. However, this mechanism
proved to be exploitable by people sending unsolicited bulk email
and as a consequence very few modern MTAs are open mail relays, and
many MTAs dont accept messages from open mail relays because such
messages are very likely to be spam. Message format The Internet
email message format is defined in RFC 5322, with multi-media
content attachments being defined in RFC 2045 through RFC 2049,
collectively called Multipurpose Internet Mail Extensions or MIME.
Prior to the introduction of RFC 2822 in 2001, the format described
by RFC 822 was the standard for Internet email for nearly 20 years.
RFC 822 was published in 1982 and based on the earlier RFC 733 for
the ARPANET (see).[34] Internet email messages consist of two major
sections: Header Structured into fields such as From, To, CC,
Subject, Date, and other information about the email. Body The
basic content, 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. Message header Each message has exactly one header, which is
structured into fields. Each field has a name and a value. RFC 5322
specifies the precise syntax. Informally, each line of text in the
header that begins with a printable character begins a separate
field. The field name starts in the first character of the line and
ends before the separator character ":". The separator is then
followed by the field value (the "body" of the field). The value 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 be represented using
MIME encoded words.
11. Email 9 Header fields The message header must include at
least the following fields[35] : From: The email address, and
optionally the name of the author(s). In many email clients not
changeable except through changing account settings. 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 recipients client may then display the time in the format and
time zone local to him/her. The message header should include at
least the following fields[36] : Message-ID: Also an automatically
generated field; used to prevent multiple delivery and for
reference in In-Reply-To: (see below). In-Reply-To: Message-ID of
the message that this is a reply to. Used to link related messages
together. This field only applies for reply messages. RFC 3864
describes registration procedures for message header fields at the
IANA; it provides for permanent [37] and provisional [38] message
header field names, including also fields defined for MIME,
netnews, and http, and referencing relevant RFCs. Common header
fields for email include: To: The email address(es), and optionally
name(s) of the messages 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:". 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
email clients will mark email 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. 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 email, 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.[39] 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.). Note
that the To: field is not necessarily related to the addresses to
which the message is delivered. The actual delivery list is
supplied separately to the transport protocol, SMTP, which may or
may not originally have been extracted from the header content. The
"To:" field is similar to the addressing at the top of a
conventional letter which is delivered according to the address on
the outer envelope. Also note that the "From:" field does not have
to be the real sender of the email message. One reason is that it
is very easy to fake the "From:" field and let a message seem to be
from any mail address. It is possible to digitally sign email,
which is much harder to fake, but such signatures require extra
programming and often external programs to verify. Some ISPs do not
relay email claiming to come from a domain not hosted by them, but
very few (if any) check to make sure that the person or even email
address named in the "From:" field is the one associated with the
connection. Some ISPs apply email authentication
12. Email 10 systems to email being sent through their MTA to
allow other MTAs to detect forged spam that might appear to come
from them. Recently the IETF EAI working group has defined some
experimental extensions to allow Unicode characters to be used
within the header. In particular, this allows email addresses to
use non-ASCII characters. Such characters must only be used by
servers that support these extensions. Message body Content
encoding Email was originally designed for 7-bit ASCII.[40] Much
email software is 8-bit clean but must assume it will communicate
with 7-bit servers and mail readers. The MIME standard introduced
character set specifiers and two content transfer encodings to
enable transmission of non-ASCII data: quoted printable for mostly
7 bit content with a few characters outside that range and base64
for arbitrary binary data. The 8BITMIME and BINARY extensions were
introduced to allow transmission of mail without the need for these
encodings, but many mail transport agents still do not support them
fully. In some countries, several encoding schemes coexist; as the
result, by default, the message 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, for international character sets, Unicode is growing in
popularity. Plain text and HTML Most modern graphic email clients
allow the use of either plain text or HTML for the message body at
the option of the user. HTML email messages often include an
automatically generated plain text copy as well, for compatibility
reasons. Advantages of HTML include the ability to include in-line
links and images, set apart previous messages 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, privacy concerns about web bugs, abuse
of HTML email as a vector for phishing attacks and the spread of
malicious software.[41] Some web based Mailing lists recommend that
all posts be made in plain-text, with 72 or 80 characters per
line[42] [43] for all the above reasons, but also because they have
a significant number of readers using text-based email clients such
as Mutt. Some Microsoft email clients allow rich formatting using
RTF, but unless the recipient is guaranteed to have a compatible
email client this should be avoided.[44] In order to ensure that
HTML sent in an email is rendered properly by the recipients client
software, an additional header must be specified when sending:
"Content-type: text/html". Most email programs send this header
automatically. Servers and client applications Messages are
exchanged between hosts using the Simple Mail Transfer Protocol
with software programs called mail transfer agents. Users can
retrieve their messages from servers using standard protocols such
as POP or IMAP, or, as is more likely in a large corporate
environment, with a proprietary protocol specific to Novell
Groupwise, Lotus Notes or Microsoft Exchange Servers. Webmail
interfaces allow users to access their mail with any standard web
browser, from any computer, rather than relying on an email client.
Mail can be stored on the client, on the server side, or in both
places. Standard formats for mailboxes include Maildir and mbox.
Several prominent email clients use their own proprietary format
and require conversion software to transfer email between
them.
13. Email 11 Accepting a message obliges an MTA to deliver
it,[45] and when a message cannot be delivered, that MTA must send
a bounce message back to the sender, indicating the problem.
Filename extensions Upon reception of email messages, email client
applications save message in operating system files in the
file-system. Some clients save individual messages as separate
files, while others use various 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 filename extensions: eml Used by many email
clients including Microsoft Outlook Express, Windows Mail and
Mozilla Thunderbird.[46] The files are plain text in MIME format,
containing the email 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 while also saving
separate copies of the attachments. Others separate attachments
from messages and save them in a specific directory. URI scheme
mailto: The URI scheme, as registered with the IANA, defines the
mailto: scheme for SMTP email addresses. Though its use is not
strictly defined, URLs of this form are intended to be used to open
the new message window of the users mail client when the URL is
activated, with the address as defined by the URL in the To:
field.[47] Use In society There are numerous ways in which people
have changed the way they communicate in the last 50 years; email
is certainly one of them. Traditionally, social interaction in the
local community was 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 email. Flaming Flaming occurs when a person sends a message
with angry or antagonistic content. Flaming is assumed to be more
common today because of the ease and impersonality of email
communications: confrontations in person or via telephone require
direct interaction, where social norms encourage civility, whereas
typing a message to another person is an indirect interaction, so
civility may be forgotten. Flaming is generally looked down upon by
Internet communities as it is considered rude and
non-productive.
14. Email 12 Email bankruptcy Also known as "email fatigue",
email bankruptcy is when a user ignores a large number of email
messages after falling behind in reading and answering them. The
reason for falling behind is often due to information overload and
a general sense there is so much information that it is not
possible to read it all. As a solution, people occasionally send a
boilerplate message explaining that the email inbox is being
cleared out. Harvard University law professor Lawrence Lessig is
credited with coining this term, but he may only have popularized
it.[48] In business Email was widely accepted by the business
community as the first broad electronic communication medium and
was the first e-revolution in business communication. Email is very
simple to understand and like postal mail, email 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 business user to download mail
when offline, it also provides the small business user to have
multiple users email IDs with just one email connection. Pros 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. Email 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. Email 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 email: reading, ordering, sorting,
re-contextualizing fragmented information, and writing email.[49]
The use of email is increasing due to increasing levels of
globalisationlabour division and outsourcing amongst other things.
Email 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: Email is a
push technologythe 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: Email can duplicate information. This
can be a problem when a large team is working on documents and
information while not in constant contact with the other members of
their team. Liability. Statements made in an email can be deemed
legally binding and be used against a party in a Court of law.[50]
Despite these disadvantages, email has become the most widely used
medium of communication within the business world. In fact, a 2010
study on workplace communication [51], found that 83% of U.S.
knowledge workers felt that email was critical to their success and
productivity at work.[52]
15. Email 13 Problems Attachment size limitation Email messages
may have one or more attachments. Attachments serve the purpose of
delivering binary 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 service providers implement various limitations on the
permissible size of files or the size of an entire message.
Furthermore, due to technical reasons, often a small attachment can
increase in size when sent,[53] which can be confusing to senders
when trying to assess whether they can or cannot send a file by
email, and this can result in their message being rejected. As
larger and larger file sizes are being created and traded, many
users are either forced to upload and download their files using an
FTP server, or more popularly, use online file sharing facilities
or services, usually over web-friendly HTTP, in order to send and
receive them. Information overload A December 2007 New York Times
blog post described information overload as "a $650 Billion Drag on
the Economy",[54] and the New York Times reported in April 2008
that "E-MAIL has become the bane of some peoples professional
lives" due to information overload, yet "none of the current wave
of high-profile Internet start-ups focused on e-mail really
eliminates the problem of e-mail overload because none helps us
prepare replies".[55] GigaOm posted a similar article in September
2010, highlighting research [56] that found 57% of knowledge
workers were overwhelmed by the volume of email they received.[52]
Technology investors reflect similar concerns.[57] Spamming and
computer viruses The usefulness of email is being threatened by
four phenomena: email bombardment, spamming, phishing, and email
worms. Spamming is unsolicited commercial (or bulk) email. Because
of the very low cost of sending email, spammers can send hundreds
of millions of email messages each day over an inexpensive Internet
connection. Hundreds of active spammers sending this volume of mail
results in information overload for many computer users who receive
voluminous unsolicited email each day.[58] [59] Email worms use
email as a way of replicating themselves into vulnerable computers.
Although the first email worm affected UNIX computers, the problem
is most common today on the more popular Microsoft Windows
operating system. The combination of spam and worm programs results
in users receiving a constant drizzle of junk email, which reduces
the usefulness of email 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 email. Australia also has very strict
spam laws restricting the sending of spam from an Australian
ISP,[60] but its impact has been minimal since most spam comes from
regimes that seem reluctant to regulate the sending of spam.
16. Email 14 Email spoofing Email spoofing occurs when the
header information of an email is altered to make the message
appear to come from a known or trusted source. It is often used as
a ruse to collect personal information. Email bombing Email bombing
is the intentional sending of large volumes of messages to a target
address. The overloading of the target email address can render it
unusable and can even cause the mail server to crash. Privacy
concerns Today it can be important to distinguish between Internet
and internal email systems. Internet email may travel and be stored
on networks and computers without the senders or the recipients
control. During the transit time it is possible that third parties
read or even modify the content. Internal mail systems, in which
the information never leaves the organizational network, may be
more secure, although information technology personnel and others
whose function may involve monitoring or managing may be accessing
the email of other employees. Email privacy, without some security
precautions, can be compromised because: email messages are
generally not encrypted. email 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 email
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 email 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. For example, Virtual Private Networks or the Tor anonymity
network can be used to encrypt traffic from the user machine to a
safer network while GPG, PGP, SMEmail,[61] or S/MIME can be used
for end-to-end message encryption, and SMTP STARTTLS or SMTP over
Transport Layer Security/Secure Sockets Layer can be used to
encrypt communications for a single mail hop between the SMTP
client and the SMTP server. Additionally, many mail user agents do
not protect logins and passwords, making them easy to intercept 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. Tracking of sent mail The original SMTP mail
service provides limited mechanisms for tracking a transmitted
message, and none for verifying that it has been delivered or read.
It requires that each mail server must either deliver it onward or
return a failure notice (bounce message), but both software bugs
and system failures can cause messages to be lost. To remedy this,
the IETF introduced Delivery Status Notifications (delivery
receipts) and Message Disposition Notifications (return receipts);
however, these are not universally deployed in production. (A
complete Message Tracking mechanism was also defined, but it never
gained traction; see RFCs 3885 through 3888.) Many ISPs now
deliberately disable non-delivery reports (NDRs) and delivery
receipts due to the activities of spammers: 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 email address that was used can be
flooded with NDRs from the many invalid email addresses the spammer
may have attempted to mail.
17. Email 15 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 been opened.[62] [63] [64] The
receiver could also let the sender know that the emails have been
opened through an "Okay" button. A check sign can appear in the
senders screen when the receivers "Okay" button is pressed. US
Government The US Government has been involved in email in several
different ways. Starting in 1977, the US Postal Service (USPS)
recognized that electronic mail and electronic transactions posed a
significant threat to First Class mail volumes and revenue.
Therefore, the USPS initiated an experimental email service known
as E-COM. Electronic messages were transmitted to a post office,
printed out, and delivered as hard copy. To take advantage of the
service, an individual had to transmit at least 200 messages. The
delivery time of the messages was the same as First Class mail and
cost 26 cents. Both the Postal Regulatory Commission and the
Federal Communications Commission opposed E-COM. The FCC concluded
that E-COM constituted common carriage under its jurisdiction and
the USPS would have to file a tariff.[65] Three years after
initiating the service, USPS canceled E-COM and attempted to sell
it off.[66] [67] [68] [69] [70] [71] The early ARPANET dealt with
multiple email clients that had various, and at times incompatible,
formats. For example, in the system Multics, the "@" sign meant
"kill line" and anything after the "@" sign was ignored.[69] The
Department of Defense DARPA desired to have uniformity and
interoperability for email and therefore funded efforts to drive
towards unified inter-operable standards. This led to David
Crocker, John Vittal, Kenneth Pogran, and Austin Henderson
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 BBN to 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), which includes an appendix listing the varying
email systems at the time. This, in turn, lead to the release of
David Crockers RFC 822, "Standard for the Format of ARPA Internet
Text Messages" (August 13, 1982).[72] The National Science
Foundation took over operations of the ARPANET and Internet from
the Department of Defense, and initiated NSFNet, a new backbone for
the network. A part of the NSFNet AUP forbade commercial
traffic.[73] In 1988, Vint Cerf arranged for an interconnection of
MCI Mail with NSFNET on an experimental basis. The following year
Compuserve email interconnected with NSFNET. Within a few years the
commercial traffic restriction was removed from NSFNETs AUP, and
NSFNET was privatised. In the late 1990s, the Federal Trade
Commission grew concerned with fraud transpiring in email, and
initiated a series of procedures on spam, fraud, and phishing.[74]
In 2004, FTC jurisdiction over spam was codified into law in the
form of the CAN SPAM Act.[75] Several other US Federal Agencies
have also exercised jurisdiction including the Department of
Justice and the Secret Service.
18. Email 16 References [1] Klensin, J (October 2008). "RFC
5321 Simple Mail Transfer Protocol" (http:/ / tools. ietf. org/
html/ rfc5321#section-2. 3. 11). Network Working Group. . Retrieved
2010-02-27. [2] Long, Tony (23 October 2000). A Matter of (Wired
News) Style (http:/ / www. nettime. org/ Lists-Archives/
nettime-bold-0010/ msg00471. html). Wired magazine. . [3] Readers
on (Wired News) Style (http:/ / www. wired. com/ culture/
lifestyle/ news/ 2000/ 10/ 39651). Wired magazine. 24 October 2000.
. [4] "RFC Editor Terms List" (http:/ / www. rfc-editor. org/
rfc-style-guide/ terms-online-03. txt). IETF. . [5] Yahoo style
guide (http:/ / styleguide. yahoo. com/ word-list/ e) [6] AP
Stylebook editors share big changes (http:/ / www. aces2011. org/
sessions/ 18/ the-ap-stylebook-editors-visit-aces-2011/ ) from the
American Copy Editors Society [7] Gerri Berendzen; Daniel Hunt. "AP
changes e-mail to email" (http:/ / www. aces2011. org/ sessions/
18/ the-ap-stylebook-editors-visit-aces-2011/ ). 15th National
Conference of the American Copy Editors Society (2011, Phoenix).
ACES. . Retrieved 23 March 2011. [8] AskOxford Language Query team.
"What is the correct way to spell e words such as email, ecommerce,
egovernment?" (http:/ / www. askoxford. com/ asktheexperts/ faq/
aboutspelling/ email). FAQ. Oxford University Press. . Retrieved 4
September 2009. "We recommend email, as this is now by far the most
common form" [9] Reference.com (http:/ / dictionary. reference.
com/ browse/ email) [10] Random House Unabridged Dictionary, 2006
[11] The American Heritage Dictionary of the English Language,
Fourth Edition [12] Princeton University WordNet 3.0 [13] The
American Heritage Science Dictionary, 2002 [14] ""Email" or
"e-mail"" (http:/ / english. stackexchange. com/ questions/ 1925/
email-or-e-mail). English Language & Usage Stack Exchange.
August 25, 2010. . Retrieved September 26, 2010. [15] RFC 821
(rfc821) - Simple Mail Transfer Protocol (http:/ / www. faqs. org/
rfcs/ rfc821. html) [16] RFC 1939 (rfc1939) - Post Office Protocol
- Version 3 (http:/ / www. faqs. org/ rfcs/ rfc1939. html) [17] RFC
3501 (rfc3501) - Internet Message Access Protocol - version 4rev1
(http:/ / www. faqs. org/ rfcs/ rfc3501. html) [18] "RFC Style
Guide", Table of decisions on consistent usage in RFC (http:/ /
www. rfc-editor. org/ rfc-style-guide/ terms-online-03. txt) [19]
Excerpt from the FAQ list of the Usenet newsgroup alt.usage.english
(http:/ / alt-usage-english. org/ excerpts/ fxhowdoy. html) [20]
See (Partridge 2008) for early history of email, from origins
through 1991. [21] "CTSS, Compatible Time-Sharing System"
(September 4, 2006), University of South Alabama, USA-CTSS (http:/
/ www. cis. usouthal. edu/ faculty/ daigle/ project1/ ctss. htm).
[22] Tom Van Vleck, "The IBM 7094 and CTSS" (September 10, 2004),
Multicians.org (Multics), web: Multicians-7094 (http:/ / www.
multicians. org/ thvv/ 7094. html). [23] Tom Van Vlecks memoir of
The History of Electronic Mail (http:/ / www. multicians. org/
thvv/ mail-history. html) [24] APL Quotations and Anecdotes (http:/
/ www. jsoftware. com/ papers/ APLQA. htm), including Leslie
Goldsmiths story of the Mailbox [25] History of the Internet,
including Carter/Mondale use of email (http:/ / www. actewagl. com.
au/ Education/ communications/ Internet/ historyOfTheInternet/
InternetOnItsInfancy. aspx) [26] Version 3 Unix mail(1) manual page
from 10/25/1972 (http:/ / minnie. tuhs. org/ cgi-bin/ utree.
pl?file=V3/ man/ man1/ mail. 1) [27] Version 6 Unix mail(1) manual
page from 2/21/1975 (http:/ / minnie. tuhs. org/ cgi-bin/ utree.
pl?file=V6/ usr/ man/ man1/ mail. 1) [28] Gordon Bells timeline of
Digital Equipment Corporation (https:/ / research. microsoft. com/
en-us/ um/ people/ gbell/ Digital/ timeline/ 1982. htm) [29]
Version 7 Unix manual: "UUCP Implementation Description" by D. A.
Nowitz, and "A Dial-Up Network of UNIX Systems" by D. A. Nowitz and
M. E. Lesk (http:/ / cm. bell-labs. com/ 7thEdMan/ vol2/ uucp. bun)
[30] Email History (http:/ / www. livinginternet. com/ e/ ei. htm)
[31] The First Email (http:/ / openmap. bbn. com/ ~tomlinso/ ray/
firstemailframe. html) [32] Wave New World,Time Magazine, October
19, 2009, p.48 [33] How E-mail Works (http:/ / www. webcastr. com/
videos/ informational/ how-email-works. html). [internet video].
howstuffworks.com. 2008. . [34] Simpson, Ken (October 3, 2008). "An
update to the email standards" (http:/ / blog. mailchannels. com/
2008/ 10/ update-to-email-standards. html). Mail Channels Blog
Entry. . [35] RFC 5322, 3.6. Field Definitions (http:/ / tools.
ietf. org/ html/ rfc5322#section-3. 6) [36] RFC 5322, 3.6.4.
Identification Fields (http:/ / tools. ietf. org/ html/
rfc5322#section-3. 6. 4) [37] http:/ / www. iana. org/ assignments/
message-headers/ perm-headers. html [38] http:/ / www. iana. org/
assignments/ message-headers/ prov-headers. html [39] Microsoft,
Auto Response Suppress, 2010, microsoft reference (http:/ / msdn.
microsoft. com/ en-us/ library/ ee219609(v=EXCHG. 80). aspx), 2010
Sep 22 [40] Craig Hunt (2002). TCP/IP Network Administration.
OReilly Media. pp.70. ISBN978-0596002978. [41] "Email policies that
prevent viruses" (http:/ / advosys. ca/ papers/ mail-policies.
html). .
19. Email 17 [42] "When posting to a RootsWeb mailing list..."
(http:/ / helpdesk. rootsweb. com/ listadmins/ plaintext. html)
[43] "...Plain text, 72 characters per line..." (http:/ / www.
openbsd. org/ mail. html) [44] How to Prevent the Winmail.dat File
from Being Sent to Internet Users (http:/ / support. microsoft.
com/ kb/ 138053) [45] In practice, some accepted messages may
nowadays not be delivered to the recipients InBox, but instead to a
Spam or Junk folder which, especially in a corporate environment,
may be inaccessible to the recipient [46] "File Extension .EML
Details" (http:/ / filext. com/ file-extension/ EML). FILExt - The
File Extension Source. . Retrieved 2009-09-26. [47] RFC 2368
section 3 : by Paul Hoffman in 1998 discusses operation of the
"mailto" URL. [48] Barrett, Grant (December 23, 2007). "All We Are
Saying." (http:/ / www. nytimes. com/ 2007/ 12/ 23/ weekinreview/
23buzzwords. html?ref=weekinreview). New York Times. . Retrieved
2007-12-24. [49] "Email Right to Privacy - Why Small Businesses
Care" (http:/ / www. smallbiztrends. com/ 2007/ 06/
email-has-right-to-privacy-why-small-businesses-care. html). Anita
Campbell. 2007-06-19. . [50] C. J. Hughes (February 17, 2011).
"E-Mail May Be Binding, State Court Rules" (http:/ / www. nytimes.
com/ 2011/ 02/ 20/ realestate/ 20posting. html). New York Times. .
Retrieved 2011-02-20. [51] http:/ / www. plantronics. com/
north_america/ en_US/ howwework/ [52] By Om Malik, GigaOm. Is Email
a Curse or a Boon? (http:/ / gigaom. com/ collaboration/
is-email-a-curse-or-a-boon/ ) September 22, 2010. Retrieved October
11, 2010. [53] "Exchange 2007: Attachment Size Increase,..."
(http:/ / technet. microsoft. com/ en-us/ magazine/ 2009. 01.
exchangeqa. aspx?pr=blog). TechNet Magazine, Microsoft.com US.
2010-03-25. . [54] Lohr, Steve (2007-12-20). "Is Information
Overload a $650 Billion Drag on the Economy?" (http:/ / bits.
blogs. nytimes. com/ 2007/ 12/ 20/
is-information-overload-a-650-billion-drag-on-the-economy). New
York Times. . Retrieved May 1, 2010. [55] Stross, Randall
(2008-04-20). "Struggling to Evade the E-Mail Tsunami" (http:/ /
www. nytimes. com/ 2008/ 04/ 20/ technology/ 20digi. html?_r=2&
oref=slogin& oref=slogin). New York Times. . Retrieved May 1,
2010. [56] http:/ / gigaom. com/ collaboration/
is-email-a-curse-or-a-boon/ [57] "Did Darwin Skip Over Email?"
(http:/ / www. foundrygroup. com/ blog/ archives/ 2008/ 04/
did-darwin-skip-over-email. php). Foundry Group. 2008-04-28. . [58]
Rich Kawanagh. The top ten email spam list of 2005. ITVibe news,
2006, january 02, ITvibe.com (http:/ / itvibe. com/ news/ 3837/ )
[59] How Microsoft is losing the war on spam Salon.com (http:/ /
dir. salon. com/ story/ tech/ feature/ 2005/ 01/ 19/
microsoft_spam/ index. html) [60] Spam Bill 2003 ( PDF (http:/ /
www. aph. gov. au/ library/ pubs/ bd/ 2003-04/ 04bd045. pdf)) [61]
M. Toorani, SMEmail - A New Protocol for the Secure E-mail in
Mobile Environments (http:/ / ieeexplore. ieee. org/ xpl/
freeabs_all. jsp?arnumber=4783292), Proceedings of the Australian
Telecommunications Networks and Applications Conference (ATNAC08),
pp.39-44, Adelaide, Australia, December 2008. (arXiv:1002.3176)
[62] About.com (http:/ / email. about. com/ od/
emailbehindthescenes/ a/ html_return_rcp. htm) [63]
Webdevelopersnotes.com (http:/ / www. webdevelopersnotes. com/
tips/ yahoo/ notification-when-yahoo-email-is-opened. php) [64]
Microsoft.com (http:/ / support. microsoft. com/ kb/ 222163) [65]
In re Request for declaratory ruling and investigation by Graphnet
Systems, Inc., concerning the proposed E-COM service, FCC Docket
No. 79-6 (September 4, 1979) [66] History of the United States
Postal Service, USPS (http:/ / www. usps. com/ history/ history/
his1. htm) [67] Hardy, Ian R; The Evolution of ARPANET Email
(http:/ / www. archive. org/ web/ */ http:/ www. ifla. org/
documents/ internet/ hari1. txt); 1996-05-13; History Thesis Paper;
University of California at Berkeley [68] James Bovard, The Law
Dinosaur: The US Postal Service, CATO Policy Analysis (February
1985) [69] Jay Akkad, The History of Email (http:/ / www. cs. ucsb.
edu/ ~almeroth/ classes/ F04. 176A/ homework1_good_papers/
jay-akkad. html) [70] US Postal Service: Postal Activities and Laws
Related to Electronic Commerce, GAO-00-188 (http:/ / www. gao. gov/
archive/ 2000/ gg00188. pdf) [71] Implications of Electronic Mail
and Message Systems for the U.S. Postal Service , Office of
Technology Assessment, Congress of the United States, August 1982
(http:/ / govinfo. library. unt. edu/ ota/ Ota_4/ DATA/ 1982/ 8214.
PDF) [72] Email History, How Email was Invented, Living Internet
(http:/ / www. livinginternet. com/ e/ ei. htm) [73] Cybertelecom :
Internet History (http:/ / www. cybertelecom. org/ notes/
internet_history80s. htm) [74] Cybertelecom : SPAM Reference
(http:/ / www. cybertelecom. org/ spam/ Spamref. htm) [75]
Cybertelecom : Can Spam Act (http:/ / www. cybertelecom. org/ spam/
canspam. htm)
20. Email 18 Further reading Cemil Betanov, Introduction to
X.400, Artech House, ISBN 0-89006-597-7. Lawrence Hughes, Internet
e-mail Protocols, Standards and Implementation, Artech House
Publishers, ISBN 0-89006-939-5. Kevin Johnson, Internet Email
Protocols: A Developers Guide, Addison-Wesley Professional, ISBN
0-201-43288-9. Pete Loshin, Essential Email Standards: RFCs and
Protocols Made Practical, John Wiley & Sons, ISBN
0-471-34597-0. Partridge, Craig (AprilJune 2008). "The Technical
Development of Internet Email" (http://www.ir.bbn.com/
~craig/email.pdf) (PDF). IEEE Annals of the History of Computing
(Berlin: IEEE Computer Society) 30 (2). ISSN1934-1547 Sara
Radicati, Electronic Mail: An Introduction to the X.400 Message
Handling Standards, Mcgraw-Hill, ISBN 0-07-051104-7. John Rhoton,
Programmers Guide to Internet Mail: SMTP, POP, IMAP, and LDAP,
Elsevier, ISBN 1-55558-212-5. John Rhoton, X.400 and SMTP: Battle
of the E-mail Protocols, Elsevier, ISBN 1-55558-165-X. David Wood,
Programming Internet Mail, OReilly, ISBN 1-56592-479-7. External
links E-mail (http://www.dmoz.org/Computers/Internet/E-mail//) at
the Open Directory Project IANAs list of standard header fields
(http://www.iana.org/assignments/message-headers/perm-headers.html)
The History of Electronic Mail
(http://www.multicians.org/thvv/mail-history.html) is a personal
memoir by the implementer of an early email system
21. Instant messaging 19 Instant messaging Instant messaging
(IM) is a form of real-time direct text-based communication between
two or more people using personal computers or other devices, along
with shared clients. The users text is conveyed over a network,
such as the Internet. More advanced instant messaging software
clients also allow enhanced modes of communication, such as live
voice or video calling. Definition IM falls under the umbrella term
online chat, as it is a real-time text-based networked
communication system, but is distinct in that it is based on
clients that facilitate connections between specified known users
(often using "Buddy List", "Friend List" or "Contact List"),
whereas online chat also includes web-based applications that allow
communication between (often anonymous) users in a multi-user
environment. Overview Instant messaging (IM) is a collection of
technologies used for real-time text-based communication between
two or more participants over the Internet, or other types of
networks. Of importance is that online chat and instant messaging
differs from other technologies such as e-mail due to Pidgin 2.0
running under GNOME the perceived synchronicity of the
communications by the users chat happens in real-time. Some systems
permit messages to be sent to people not currently logged on
(offline messages), thus removing some of the differences between
IM and e-mail (often done by sending the message to the associated
e-mail account). IM allows effective and efficient communication,
allowing immediate receipt of acknowledgment or reply. In many
cases instant messaging includes additional features which can make
it even more popular. For example, users can see each other by
using webcams, or talk directly for free over the Internet using a
microphone and headphones or loudspeakers. Many client programs
allow file transfers as well, although they are typically limited
in the permissible file-size. It is typically possible to save a
text conversation for later reference. Instant messages are often
logged in a local message history, making it similar to the
persistent nature of e-mails.
22. Instant messaging 20 History Instant messaging predates the
Internet, first appearing on multi-user operating systems like CTSS
and Multics[1] in the mid-1960s. Initially, some of these systems
were used as notification systems for services like printing, but
quickly were used to facilitate communication with other users
logged in to the same machine. As networks developed, the protocols
spread with the networks. Some of these used a peer-to-peer
protocol (e.g. talk, ntalk and ytalk), while others required peers
to connect to a server (see talker and IRC). During the Bulletin
board system (BBS) phenomenon that In early instant messaging
programs each character appeared when it was typed. peaked during
the 1980s, some systems The UNIX "talk" command shown in this
screenshot was popular in the 1980s and incorporated chat features
which were early 1990s. similar to instant messaging; Freelancin
Roundtable was one prime example. The first[2] dedicated online
chat service was the CompuServe CB Simulator in 1980,[3] created by
CompuServe executive Alexander "Sandy" Trevor in Columbus, Ohio. In
the latter half of the 1980s and into the early 1990s, the Quantum
Link online service for Commodore 64 computers offered user-to-user
messages between currently connected customers, which they called
"On-Line Messages" (or OLM for short), and later "FlashMail."
(Quantum Link later became America Online and made AOL Instant
Messenger (AIM), discussed later). While the Quantum Link service
ran on a Commodore 64, using only the Commodores PETSCII
text-graphics, the screen was visually divided up into sections and
OLMs would appear as a yellow bar saying "Message From:" and the
name of the sender along with the message across the top of
whatever the user was already doing, and presented a list of
options for responding.[4] As such, it could be considered a sort
of GUI (Graphical User Interface), albeit much more primitive than
the later Unix, Windows and Macintosh based GUI IM software. OLMs
were what Q-Link called "Plus Services" meaning they charged an
extra per-minute fee on top of the monthly Q-Link access costs.
Modern, Internet-wide, GUI-based messaging clients as they are
known today, began to take off in the mid 1990s with PowWow, ICQ,
and AOL Instant Messenger. Similar functionality was offered by
CU-SeeMe in 1992; though primarily an audio/video chat link, users
could also send textual messages to each other. AOL later acquired
Mirabilis, the authors of ICQ; a few years later ICQ (now owned by
AOL) was awarded two patents for instant messaging by the U.S.
patent office. Meanwhile, other companies developed their own
software; (Excite, MSN, Ubique, and Yahoo), each with its own
proprietary protocol and client; users therefore had to run
multiple client applications if they wished to use more than one of
these networks. In 1998, IBM released IBM Lotus Sametime, a product
based on technology acquired when IBM bought Haifa-based Ubique and
Lexington-based Databeam. In 2000, an open source application and
open standards-based protocol called Jabber was launched. The
protocol was standardized under the name Extensible Messaging and
Presence Protocol (XMPP). XMPP servers could act as gateways to
other IM protocols, reducing the need to run multiple clients.
Multi-protocol clients can use any of the popular IM protocols by
using additional local libraries for each protocol. IBM Lotus
Sametimes November 2007 release added IBM Lotus Sametime Gateway
support for XMPP. In the current era, social networking providers
often offer IM capabilities.
23. Instant messaging 21 Many instant messaging services offer
video calling features, Voice Over IP (VoIP) and web conferencing
services. Web conferencing services can integrate both video
calling and instant messaging capabilities. Some instant messaging
companies are also offering desktop sharing, IP radio, and IPTV to
the voice and video features. The term "Instant Messenger" is a
service mark of Time Warner[5] and may not be used in software not
affiliated with AOL in the United States. For this reason, the
instant messaging client formerly known as Gaim (or gaim)
announced, in April 2007, that they would be renamed "Pidgin".[6]
Clients Each modern IM service generally provides its own client,
either a separately installed piece of software, or a browser-based
client. These typically only work with that particular companys
service, although some allow limited function with other services.
There are also third party client software applications that will
connect with most of the major IM services. Adium, Digsby, Jappix,
Meebo, Miranda IM, Pidgin, Qnext and Trillian are a few of the
common ones. Interoperability Standard, complimentary instant
messaging applications offer functions like file transfer, contact
list(s), the ability to hold several simultaneous conversations,
etc. These may be all the functions that a small business needs,
but larger organizations will require more sophisticated
applications that can work together. The solution to finding
applications capable of this is to use enterprise versions of
instant messaging applications. These include titles like XMPP,
Lotus Sametime, Microsoft Office Communicator, etc., which are
often integrated with other enterprise applications such as
workflow systems. These enterprise applications, or Enterprise
Application Integration (EAI), are built to certain constraints,
namely storing data in a common format. There have been several
attempts to create a unified standard for Pidgins tabbed chat
window in Linux instant messaging: IETFs SIP (Session Initiation
Protocol) and SIMPLE (SIP for Instant Messaging and Presence
Leveraging Extensions), APEX (Application Exchange), Prim (Presence
and Instant Messaging Protocol), the open XML-based XMPP
(Extensible Messaging and Presence Protocol), and Open Mobile
Alliances Instant Messaging and Presence Service developed
specifically for mobile devices. Most attempts at producing a
unified standard for the major IM providers (AOL, Yahoo! and
Microsoft) have failed, and each continues to use its own
proprietary protocol. However, while discussions at IETF were
stalled, Reuters signed the first inter-service provider
connectivity agreement on September 2003. This agreement enabled
AIM, ICQ and MSN Messenger users to talk with Reuters Messaging
counterparts and vice-versa. Following this, Microsoft, Yahoo! and
AOL agreed a deal in which Microsofts Live Communications Server
2005 users would also have the possibility to talk to public
instant messaging users. This deal established SIP/SIMPLE as a
standard for protocol interoperability and established a
connectivity fee for accessing public instant messaging groups or
services. Separately, on 13 October 2005, Microsoft and Yahoo!
announced that by the 3rd quarter of 2006 they would interoperate
using SIP/SIMPLE, which was followed, in December 2005, by the AOL
and Google strategic partnership deal in which Google Talk users
would be able to communicate with AIM and ICQ users provided they
have an AIM account. There are two ways to combine the many
disparate protocols:
24. Instant messaging 22 Combine the many disparate protocols
inside the IM client application. Combine the many disparate
protocols inside the IM server application. This approach moves the
task of communicating with the other services to the server.
Clients need not know or care about other IM protocols. For
example, LCS 2005 Public IM Connectivity. This approach is popular
in XMPP servers; however, the so-called transport projects suffer
the same reverse engineering difficulties as any other project
involved with closed protocols or formats. Some approaches allow
organizations to deploy their own, private instant messaging
network by enabling them to restrict access to the server (often
with the IM network entirely behind their firewall) and administer
user permissions. Other corporate messaging systems allow
registered users to also connect from outside the corporation LAN,
by using an encrypted, firewall-friendly, HTTPS-based protocol.
Typically, a dedicated corporate IM server has several advantages,
such as pre-populated contact lists, integrated authentication, and
better security and privacy. Certain networks have made changes to
prevent them from being utilized by such multi-network IM clients.
For example, Trillian had to release several revisions and patches
to allow its users to access the MSN, AOL, and Yahoo! networks,
after changes were made to these networks. The major IM providers
typically cite the need for formal agreements as well as security
concerns as reasons for making these changes. The use of
proprietary protocols has meant that many instant messaging
networks have been incompatible and people have been unable to
reach friends on other networks. This has cost the instant
messaging format dearly.[7] Mobile instant messaging Mobile Instant
Messaging (MIM) is the technology that allows Instant Messaging
services to be accessed from a portable device, ranging from
standard mobile phones, to smartphones (e.g. devices using
operating systems such as iOS, Blackberry OS, Symbian OS, Android
OS, Windows Mobile, et al.). It is done two ways: Embedded Clients
- tailored IM client for every specific device. Clientless Platform
a browser-based application that does not require downloading any
software to the handset, and which enables all users and all
devices from any network to connect to their Internet IM service
ideally. In practice, browser capabilities can pose problems. In
web browser Gmail has instant messaging capacity in webpage itself,
which can be used in a web browser without the need to download and
install the IM client. Later Yahoo and Hotmail also implemented it.
eBuddy and Meebo websites offers instant messaging of different IM
services. Generally such services are limited to text chat,
although Gmail has voice and video capabilities. As of August 2010,
Gmail allows the calling of regular phones from their web-based IM
client. Jappix is a XMPP web-client, offering the user a complete
XMPP protocol features access, through his web browser. It is
declined in three versions: a desktop one, a mobile one and a mini
one. The last one, Jappix Mini, is a mini chat for websites.
25. Instant messaging 23 Friend-to-friend networks Instant
Messaging may be done in a Friend-to-friend network, in which each
node connects to the friends on the friends list. This allows for
communication with friends of friends and for the building of
chatrooms for instant messages with all friends on that network. IM
language Users sometimes make use of internet slang or text speak
to abbreviate common words or expressions in order to quicken
conversations or to reduce keystrokes. The language has become
universal, with well-known expressions such as lol translated over
to face to face language. Emotions are often expressed in
shorthand, such as the abbreviation LOL, BRB and TTYL (respectively
Laugh(ing) Out Loud, Be Right Back and Talk To You Later). Some,
however, attempt to be more accurate with emotional expression over
IM. Real time reactions such as (chortle) (snort) (guffaw) or
(eye-roll) are becoming more popular. Also there are certain
standards that are being introduced into mainstream conversations
including, # indicates the use of sarcasm in a statement and *
which indicates a spelling mistake and/or grammatical error in the
previous message, followed by a correction.[8] Business application
Instant messaging has proven to be similar to personal computers,
e-mail, and the World Wide Web, in that its adoption for use as a
business communications medium was driven primarily by individual
employees using consumer software at work, rather than by formal
mandate or provisioning by corporate information technology
departments. Tens of millions of the consumer IM accounts in use
are being used for business purposes by employees of companies and
other organizations. In response to the demand for business-grade
IM and the need to ensure security and legal compliance, a new type
of instant messaging, called "Enterprise Instant Messaging" ("EIM")
was created when Lotus Software launched IBM Lotus Sametime in
1998. Microsoft followed suit shortly thereafter with Microsoft
Exchange Instant Messaging, later created a new platform called
Microsoft Office Live Communications Server, and released Office
Communications Server 2007 in October 2007. Oracle Corporation has
also jumped into the market recently with its Oracle Beehive
unified collaboration software.[9] Both IBM Lotus and Microsoft
have introduced federation between their EIM systems and some of
the public IM networks so that employees may use a single interface
to both their internal EIM system and their contacts on AOL, MSN,
and Yahoo!. Current leading EIM platforms include IBM Lotus
Sametime, Microsoft Office Communications Server, Jabber XCP and
Cisco Unified Presence. In addition, industry-focused EIM platforms
as Reuters Messaging and Bloomberg Messaging provide enhanced IM
capabilities to financial services companies. The adoption of IM
across corporate networks outside of the control of IT
organizations creates risks and liabilities for companies who do
not effectively manage and support IM use. Companies implement
specialized IM archiving and security products and services to
mitigate these risks and provide safe, secure, productive instant
messaging capabilities to their employees.
26. Instant messaging 24 Review of products IM products can
typically be categorised into two types: Enterprise Instant
Messaging (EIM)[10] and Consumer Instant Messaging (CIM).[11]
Enterprise solutions use an internal IM server, however this isnt
always feasible, particularly for smaller businesses with limited
budgets. The second option, using a CIM provides the advantage of
being inexpensive to implement and has little need for investing in
new hardware or server software. For corporate use encryption and
conversation archiving are usually regarded as important features
due to security concerns. Sometimes the use of different operating
systems in organizations calls for the use of software that
supports more than one platform. For example many software
companies use Windows XP in administration departments but have
software developers who use Linux. Risks and liabilities Although
instant messaging delivers many benefits, it also carries with it
certain risks and liabilities, particularly when used in
workplaces. Among these risks and liabilities are: Security risks
(e.g. IM used to infect computers with spyware, viruses, trojans,
worms) Compliance risks Inappropriate use Trade secret leakage
Security risks Crackers (malicious "hacker" or [black hat] hacker)
have consistently used IM networks as vectors for delivering
phishing attempts, "poison URLs", and virus-laden file attachments
from 2004 to the present, with over 1100 discrete attacks listed by
the IM Security Center[12] in 2004-2007. Hackers use two methods of
delivering malicious code through IM: delivery of viruses, trojan
horses, or spyware within an infected file, and the use of
"socially engineered" text with a web address that entices the
recipient to click on a URL connecting him or her to a website that
then downloads malicious code. Viruses, computer worms, and trojans
typically propagate by sending themselves rapidly through the
infected users buddy list. An effective attack using a poisoned URL
may reach tens of thousands of people in a short period when each
persons buddy list receives messages appearing to be from a trusted
friend. The recipients click on the web address, and the entire
cycle starts again. Infections may range from nuisance to criminal,
and are becoming more sophisticated each year. IM connections
usually take place in plain text, making them susceptible to
eavesdropping. In addition, IM client software often requires the
user to expose open UDP ports to the world, increasing the threat
posed by potential security vulnerabilities.[13] Compliance risks
In addition to the malicious code threat,