TCP/IP: A Brief Synopsis of Standards

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TCP/IPA Brief Synopsis of Standards
The NSF Backbone, Circa 1995 Donna Cox, The
National Center for Supercomputing Applications
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TCP/IP gets its name from the two most commonly
used protocols in the Internet Protocol Suite
(IPv4)
Transmission Control Protocol RFC 793 of the
Internet Engineering Task Force (IETF) (RFC 1122
for clarifications and RFC 1323 for
extensions) STD 7 of the Internet Engineering
Task Force (IETF) Internet Protocol RFC 791 of
the Internet Engineering Task Force (IETF) STD 5
of the Internet Engineering Task Force
(IETF) As UNIX gained popularity, so did
TCP/IP. Acceptance of TCP/IP is due largely in
part to its original implementation in UNIX,
which gained popularity in academic
environments.
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Requests for Comments (RFCs) RFCs are a series of
notes, started in 1969, about the
Internetoriginally the ARPANET. These notes
discuss the aspects of computer communication,
focusing on networking protocols, procedures,
programs, and concepts. This is an informal forum
which can also include meeting notes, opinion,
and sometimes humor. RFCs can be found
online http//www.rfc-editor.org The
specification documents of the Internet protocol
suite, as defined by the Internet Engineering
Task Force (IETF) and its steering group the
IESG, are published as RFCs. Specifications that
are intended to become Internet Standards evolve
through a set of maturity levels known as the
"standards track". Three maturity levels of an
RFC Proposed Standard Draft Standard
Standard
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TCP/IP is

• A layered model that groups common networking
  tasks into the same layer. Each layer uses the
  services provided by the layer below, and
  provides services to the layer above.
• A number of protocols which implement the tasks
  specified in each layer of the Open Systems
  Interconnection (OSI) communication model.
• The most common networking suite in use today.
• The basis of the Internet.

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TCP Connection-oriented protocol. Used for
providing a reliable end-to-end byte stream over
an unreliable network TCP must furnish the
reliability most users want and that IP does not
provide. (Tanenbaum 521, 523). IP
Connectionless transport protocol. Used for
providing a best-efforts way to transport
datagrams from source to destination, without
regard to whether or not these machines are on
the same network, or whether or not there are
other networks between them. (Tanenbaum
412-3) UDP Connectionless transport protocol.
Essentially IP with a short header added.
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Overview of the TCP Standard TCP fits into the
layered protocol architecture just above IP,
which provides a way for the TCP to send and
receive variable-length segments of information
enclosed in packets or datagrams. TCP services
are obtained from an end point known as a socket.
Each socket has that contains the IP address of
the host and a 16-bit number local to that host
known as a port. Port numbers below 1024 are
often referred to as well-known ports and are
therefore reserved for standard services.
Specific well-known ports include port 80 (HTTP),
port 23 (TELNET), and port 21 (FTP). To obtain
TCP services, a connection must first be made
between a socket on the sending machine and a
socket on the All TCP connections are
full-duplex (can travel in both directions
simultaneously) and point-to-point (each
connection has two end points). Calls between
sockets include the following commands SOCKET
(create a new end point), BIND (attach a local
address to a socket), LISTEN (announce that
communications will be accepted), ACCEPT (block
the caller until a connection attempt arrives),
CONNECT (attempt to establish a connection), SEND
(send data over the connection), RECEIVE (receive
data from the connection), and CLOSE (release the
connection).
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Overview of the IP Standard Each packet travels
separately through the IP network. Along the way,
routers (comparable to switches in voice
networks) read the addresses carried in the
internet header for their destinations and send
packets on their way. At the destination, the
packets are arranged in the right order and the
original message is reassembled. Since no
dedicated circuit is ever established, IP
switching frees up the network for data
exchanges, which tend to be bursty or
intermittent. If a message (datagram) is more
than 1,500 bytes, it's broken into more than one
IP packet. In theory, a datagram can be as large
as 64 Kbytes. IP also provides for
fragmentation and reassembly of long datagrams,
if necessary, for transmission through "small
packet" networks. The internet protocol treats
each internet datagram as an independent entity
unrelated to any other internet datagram. There
are no connections or logical circuits (virtual
or otherwise).
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TCP and IP Working Together
The TCP module calls on the IP module to take a
TCP segment (including the TCP header and user
data) as the data portion of an internet
datagram. The TCP module provides the addresses
and other parameters in the internet header to
the IP module as arguments of the call. The IP
module then create an internet datagram and call
on the local network interface to transmit the
internet datagram.
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Examples of RFCs and Standards Related to
TCP/IP Internet Official Protocol Standards RFC
2700, STD 1 Internet Control Message Protocol
(ICMP) RFC 792, STD 5 Broadcasting Internet
Datagrams RFC 919, STD 5 User Datagram
Protocol RFC 768, STD 6 Telnet Protocol
Specification RFC 854, STD 8 Telnet Option
Specifications RFC 855, STD 8 File Transfer
Protocol (FTP) RFC 959, STD 9 Simple Mail
Transfer Protocol RFC 821, STD 10 Domain names
- Concepts and Facilities RFC 1034, STD
13 Point-to-Point Protocol (PPP) RFC 1661, STD
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A lengthy list of current standards can found at
the RFC Editor Web site.
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IEEE 802 Group The Institute of Electrical and
Electronics Engineers, Inc LAN /MAN Standards
Committee (LMSC) LMSC (or IEEE Project 802)
develops LAN and MAN standards, mainly for the
lowest 2 layers of the Reference Model for Open
Systems Interconnection (OSI). LMSC coordinates
with other national and international standards
groups, with some standards initiated here now
published by ISO as international standards.
There is strong international participation here,
and some meetings are held outside the
U.S. Source OVERVIEW AND GUIDE TO THE IEEE
802 LMSC http//www.manta.ieee.org/groups/802/over
view2000.pdf
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IEEE 802 (LMSC) Executive Commitee
Members Chair Jim Carlo Vice Chair Paul
Nikolich Treasurer Bob Grow Recording
Secretary Howard Frazier Executive
Secretary Buzz Rigsbee Regulatory Issues
Coordinator Vic Hayes
IEEE 802.X standards can be purchased from the
IEEE Web site.
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802.4 Token Bus Working Group In hibernation
at this time Chairman Paul Eastman E-mail
paul_at_rfnetworks.com 802.5 Token Ring Working
Group In hibernation at this time Chairman
Robert D. Love E-mail rdlove_at_ieee.org 802.6
Metropolitan Area Network (MAN) Working Group In
hibernation at this time Chairman James F.
Mollenauer E-mail jmollenauer_at_technicalstrategy.c
om 802.7 BroadBand Technical Adv. Group
(BBTAG) In hibernation at this time 802.8
Fiber Optics Technical Adv. Group
(FOTAG) Disbanded Chairman J. Paul Chip
Benson, Jr. E-mail jpbenson_at_lucent.com
IEEE LMSC Groups
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802.9 Integrated Services LAN (ISLAN) Working
Group In hibernation at this time Chairman
Dhadesugoor R. Vaman E-mail dvaman_at_megaxess.com
802.10 Standard for Interoperable LAN
Security (SILS) Working Group In hibernation
at this time Chairman Kenneth G. Alonge E-mail
alonge_ken_at_geologics.com 801.11 Wireless LAN
(WLAN) Working Group Chairman Stuart
Kerry E-mail stuart.kerry_at_philips.com 802.12
Demand Priority Working Group In hibernation
at this time Chairwoman Pat Thaler E-mail
pat_thaler_at_agilent.com
IEEE LMSC Groups
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802.14 Cable-TV Based Broadband Communication
Network Working Group disbanded Chairman
Robert Russell E-mail rrussell_at_knology.com 802.1
5 Wireless Personal Area Network (WPAN) Working
Group Chairman Bob Heile E-mail
bheile_at_bbn.com 802.16 Broadband Wireless
Access (BBWA) Working Group Chairman Roger
Marks E-mail r.b.marks_at_ieee.org RPRSG Resilient
Packet Ring Study Group (RPRSG) Chairman Mike
Takefman E-mail tak_at_cisco.com
IEEE LMSC Groups
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HOW THE IEEE LMSC CREATES A STANDARD Every
recommended practice, guide, or standard starts
as a group of people with an interest in
developing the standard. A Project Authorization
Request (PAR) is normally submitted for
approval within 6 months of the start of
work. In LMSC, new projects require supporting
material to show that they meet the charter of
LMSC. The draft PAR is voted on by the Sponsor
Executive Committee (SEC), and then goes to the
IEEE Standards Board New Standards Committee
(NesCom) which recommends it for approval as an
official IEEE Standards project. Part of the PAR
identifies which outside standards groups there
will be liaisons. For example, some international
standards may require the assistance of the
International Telecommunication Union (ITU).
The liaisons help avoid conflicts or duplication
of effort in one area. Proposals are evaluated
by the working group (WG), and a draft
standard is written and voted on the by the WG.
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The work progresses from technical activities to
editorial and procedural endeavors as the draft
matures. When the WG reaches enough consensus
on the draft standard, a WG Letter Ballot is done
to release it from the WG. The draft standard is
next approved by the SEC and then goes for
Sponsor Letter Ballot. In the past, the sponsor
group was the Technical Committee on Computer
Communication, so the sponsor ballot is still
referred to sometimes as a TCCC ballot, even
though LMSC now is a sponsor and conducts its own
Sponsor Letter Ballots. After the Sponsor Letter
Ballot has passed and NO votes are
answered, the draft standard is sent to the IEEE
Standards Board Standards Review Committee
(RevCom). Once recommended by RevCom and
approved by the Standards Board, the draft
standard can then be published as an IEEE
standard. Most draft standards in LMSC are also
sent to ISO at or before the time they go
to Sponsor Letter Ballot. A parallel approval
path is followed in ISO JTC1/SC6, or the Joint
Technical Committee 1 (Information Technology
Committee), Subcommittee 6, which is responsible
for LANs. This parallel approval path then leads
to publication as an ISO standard. The process
from start to finish can take several years for
new standards, and less for revisions or addenda.
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International Organization for Standardization
(ISO) ISO JTC1/SC6 Joint Technical Committee 1,
Subcommittee 6 Telecommunications and information
exchange between systems Producers of 315 ISO
standards under the direction of the Subcommittee
(SC) Secretariat Subcommittee Secretariat Americ
an National Standards Institute (New York, NY,
USA)
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ISO JTC1/SC6 Joint Technical Committee 1,
Subcommittee 6 List of Workgroups Workgroup 1
focuses on the data link layer Convener Korean
Agency for Technology and Standards Ministry of
Commerce, Industry and Energy (Kwachon-city,
South Korea) Workgroup 3 focuses on the physical
layer Convener DIN Deutsches Institut für
Normung (Berlin, Germany) Workgroup 6 focuses on
private telecommunications networking Convener
Swiss Association for Standardization (Zurich,
Switzerland) Workgroup 7 focuses on the network
and transport layers Convener British Standards
Institution (London, UK)
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How does ISO enforce standards on a global
level? Through professional affiliations,
interaction with the international business
community, and political partnerships. ISO
together with IEC (International
Electrotechnical Commission) and ITU
(International Telecommunication Union) has built
a strategic partnership with WTO (World Trade
Organization). The political agreements reached
within the framework of WTO require underpinning
by technical agreements. ISO, IEC and ITU, as the
three principal organizations in
international standardization, have the
complementary scopes, the framework, the
expertise and the experience to provide this
technical support for the growth of the global
market. Source Standards and World
Trade http//www.iso.ch/wtotbt/wtotbt.htm
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Other than the partnerships established, is there
any kind of binding agreement that all affiliated
groups must follow? The Agreement on Technical
Barriers to Trade (TBT) sometimes referred to
as the Standards Code aims to reduce
impediments to trade resulting from differences
between national regulations and standards. As
far as international consensus-based standards
are concerned, the Agreement invites the
signatory governments to ensure that the
standardizing bodies in their countries accept
and comply with a "Code of good practice for the
preparation, adoption and application of
standards", embodied in Annex 3 to the Agreement
and which is known as the WTO Code of Good
Practice. On behalf of the WTO, the ISO/IEC
Information Centre records the acceptance of this
Code by the national standards institutes. Sourc
e Standards and World Trade http//www.iso.ch/wto
tbt/wtotbt.htm