Archive-name: cell-relay-faq/part3 Last-modified: 1997/10/06 URL: http://cell-relay.indiana.edu/cell-relay/FAQ/ATM-FAQ/FAQ.html NOTE!!!! If you are reading this FAQ as stored on some automated FAQ archive site you would be better off to follow the above http link to the most recent official version of this FAQ. Not only may it be more current but it will be better formatted than what you are viewing now! ----------------------------------------------------------------------- comp.dcom.cell-relay FAQ: ATM and related technologies (Rev 1997/10/06) Part 3 - Introduction and Topic C of FAQ ----------------------------------------------------------------------- Copyright =A9 1992, 1993, 1994, 1995, 1996, 1997 Carl Symborski Cell Relay FAQ - Introduction The Cell Relay FAQ is posted periodically in multiple parts as a Usenet News FAQ under the title comp.dcom.cell-relay FAQ: ATM, SMDS, and related technologies. This FAQ is also maintained as a collection of WEB pages (http://cell-relay.indiana.edu/cell-relay/FAQ/ATM-FAQ/FAQ.html). The WEB pages will generally be more current than the posted FAQ. In fact this FAQ is maintained as WEB pages then posted as a traditional Usenet News FAQ every few months. This article is the third of eight articles which contain general information and also answers to some Frequently Asked Questions (FAQ) which are related to or have been seen in comp.dcom.cell-relay. This FAQ provides information of general interest to both new and experienced readers. It is posted to the Usenet comp.dcom.cell-relay, comp.answers, and news.answers news groups every few months. This FAQ reflects cell-relay traffic through August 1997. If you have any additions, corrections, or suggestions for improvement to this FAQ, please send them to carl@umd5.umd.edu. I will accept suggestions for questions to be added to the FAQ, but please be aware that I will be more receptive to questions that are accompanied by answers. :-) Enjoy! Carl Symborski Vice President - Engineering SALIX Technology, Inc. carl@umd5.umd.edu cws@salix.com Carl's home page is at http://cell-relay.indiana.edu/cell-relay/FAQ/ATM-FAQ/carl/home.html --------------------------------------------------------------------------- Cell Relay FAQ - Copyright Notice and Disclaimer The Cell Relay FAQ is posted periodically in multiple parts as a Usenet News FAQ under the title comp.dcom.cell-relay FAQ: ATM, SMDS, and related technologies. This FAQ is also maintained as a collection of WEB pages. Both versions are Copyright =A9 1992-1997 Carl Symborski and may be freely redistributed in their entirety provided that this copyright notice is not removed. They may not be sold for profit or incorporated in commercial documents or CD-ROMs without the written permission of Carl Symborski. Permission is expressly granted for this document to be made available for file transfer from installations offering unrestricted anonymous file transfer on the Internet. This article is provided as is without any express or implied warranty. Nothing in this article represents the views of the University Of Maryland. --------------------------------------------------------------------------- TOPIC C ATM REFERENCES --------------------------------------------------------------------------- C1. What are some good getting started ATM references? C2. General ATM References C3. ATM information on the Internet C4. How can I get the ATM Forum's Interface Specifications? C5. List of ITU-T Recommendations concerning ATM. C6. Internet drafts from IETF working groups. C7. ATM Tutorials. C8. Contact information for ANSI T1S1 specifications. C9. Internet RFCs. C10. ATM and Related Acronyms. C11. Literature and papers on the self-similar (fractal) property of traffic? C12. How can I get copies of ITU-T documents? --------------------------------------------------------------------------- SUBJECT C1) What are some good getting started ATM references? Generally it is impossible to pick up any communications related technical journal, conference, or trade publication and not find something about ATM. However here are a few suggestions. For *beginning* reading there are all sorts of ATM primers on the web. These freely available primers are the best place to start. Several pointers can be found in subject C7 "ATM Tutorials" of this FAQ. You can find others by doing a search on the WEB. Many communication vendors have good tutorials on their WEB sites. For starters try: http://www.cisco.com http://www.trillium.com http://www.3com.com Another suggestion is to try the atmforum website and go through past issues of "53 bytes", their newsletter. There are several books recommend for *intermediate* reading. These are good for an engineer's basic understanding of most issues. Others are listed in subject C2 "General ATM References" of this FAQ. "Asynchronous Transfer Mode", Martin De Prycker, Ellis Horwood, New York 1996, ISBN 0-13-178542-7. Very readable general description of the technology and optimization. This book is now in its third edition. "ATM - solutions for enterprise internetworking", David Ginsburg, Addison-Wesley, 1996, ISBN 0-201-87701-5. "ISDN and Broadband ISDN with Frame Relay and ATM", William Stallings, third edition, Prentice-Hall, 1995, ISBN 0-02-415513-6. Third edition of Stallings ISDN book which now contains coverage of ATM and frame relay. The book is intended to be both a professional reference and a textbook. "Gigabit Networking", Craig Partridge, Addison-Wesley, Reading MA, 1993, ISBN 0-201-56333-9. Very well written book. Craig is the Editor of "IEEE Network" magazine. Topics: fiber optics, cell networking, ATM, Gbps packet schemes, applications, host interface, higher protocols, bandwidth management and performance, distributed systems, etc. For *advanced* reading I'd recommend you actually read the ATM specifications as published by the ATM Forum, and the IETF RFC's that deal with ATM: Traffic Management, UNI, MPOA, PNNI, etc. See subject C4 in the FAQ for ways to obtain ATM Forum documents. See subject C9 in the FAQ for ways to obtain IETF RFC's. --------------------------------------------------------------------------- SUBJECT C2) General ATM References Quite a lot has been written about ATM in the 80's and 90's. Most of what has been written before 1990 primarily deals with the application of ATM to Broadband ISDN. That which is written from 1990 onward cover the explosion of ATM development in the carrier environment as well as in enterprise networks, LANs, wireless, etc. Note that a subset of these references, grouped in beginner, intermediate, and advance categories are listed in subject C1 "What are some good getting started ATM References?". Please be aware that because of the pace of ATM standardization, reference books and conference proceedings rapidly become out-of-date. However, the following references offer a good base of background information. I have retained some of the older references in this list since they provide the foundation on which other applications of ATM have been based and therefore should not be over looked. General: "Issues and Challenges in ATM Networks", Communications of the ACM, February 1995, VOL. 38, NO. 2 Surveys ATM concepts and networks, security issues, traffic management, TCP/IP over ATM, etc. "Data Communications Special Guide", IEEE Spectrum, 8/91, p.22. Hi-level overview of high-speed lans, wans, bisdn, atm, with glossary and bibliography. IEEE Communications Magazine, April 1992, VOL. 30, NO. 4 This is a special issue with six articles on gigabit networks technology. Rainer Handel and Manfred Huber. "Integrated Broadband Networks: An Introduction to ATM-Based Networks". Addison-Wesley, 1991. ISBN 0-201-54444-X. "Buyer's Guide for ATM Switches," Network World, October 9, 1995, p.47. Offers a general overview of what to look for in an ATM switch and lists products (with features and prices) from 23 vendors. The full text of the article (maybe a more up to date) may be found at http://www.nwfusion.com ATM: "Asynchronous Transfer Mode", Martin De Prycker, Ellis Horwood, New York 1996, ISBN 0-13-178542-7. Very readable general description of the technology and optimization. This book is now in its third edition. "ATM - solutions for enterprise internetworking", David Ginsburg, Addison-Wesley, 1996, ISBN 0-201-87701-5. "High-Speed Networks: TCP/IP and ATM Design Principles", William Stallings, Prentice-Hall, 1997; ISBN 0-13-525965-7. "Gigabit Networking", Craig Partridge, Addison-Wesley, Reading MA, 1993, ISBN 0-201-56333-9. Very well written book. Craig is the Editor of "IEEE Network" magazine. Topics: fiber optics, cell networking, ATM, Gbps packet schemes, applications, host interface, higher protocols, bandwidth management and performance, distributed systems, etc. "ISDN and Broadband ISDN with Frame Relay and ATM", William Stallings, third edition, Prentice-Hall, 1995, ISBN 0-02-415513-6. Third edition of Stallings ISDN book which now contains coverage of ATM and frame relay. The book is intended to be both a professional reference and a textbook. "ISDN", Gary Kessler, McGraw-Hill, Second Edition, 1993. "ATM: Theory and Application", David E. McDysan and Darren L. Spohn, McGraw-Hill, 1995, ISBN 0-07-060362-6. Thorough, practical, and covers a broad range. "ATM Networks - Concepts, Protocols, Applications", Haendel R., Huber M., Schroeder S., 2nd Edition, Addison-Wesley, 1994, ISBN 0-201-42274-3. "Broadband ISDN and Asynchronous Transfer Mode (ATM)", IEEE Communications, 9/89. Describes most of the jargon as well as the paradigm and unresolved issues. One point to note is that the article is fairly old (1989) and some things have changed. For example, the ATM cell headers described are no longer valid. "Asynchronous Transfer Mode: Solution for Broadband ISDN", Martin de Prycker, Ellis Horwood, New York, 1991. ISBN 0-13-053513-3 See Martin's more recent book below. "Data and Computer Communications", 5th ed., W. Stallings. Prentice Hall 1997. Cloth. ISBN: 0-02-415425-3. Two other books mentioned: Spohn & McDysan's "ATM" book (1995, McGraw-Hill) and Walter Goralski's "ATM" book (also 1995, McGraw-Hill). No titles/ISBN as someone just mentioned them on the cell-relay list as containing info on switch architectures, etc. SMDS: "SMDS - Wide-Area Data Networking with Switched Multi-Megabit Data Service", Robert W. Klessig, Kaj Tesink, Prentice Hall, 1994, ISBN: 0-13-814807-4 SWITCH FABRICS: These papers offer a jump start on ATM switch architectures, design issues and tradeoffs. H. Ahmadi and W. Denzel, "A Survey of Modern High-Performance Switching Techniques", IEEE J on Selected Areas in Comm, Vol. 7, No. 7, Sept 1989, p. 1091-1103 F. Tobagi, "Fast Packet Switch Architectures for Broad-band Integrated Services Digital Networks", Proceedings of IEEE, Vol. 78, No. 1, Jan. 1990 p. 133-167 Joseph Y. Hui, "Switching and Traffic Theory for Integrated Broadband Networks", Kluwer Academic Publishers, 1991, ISBN 0-7923-9061-X A back to basics text book explaining core switching concepts like batcher/banyon, clos, min, buffering, etc. Technical journals (an easy source of information) IEEE Network IEEE Communications IEEE Journal on Selected Areas in Communications IEEE Transactions on Communications IEEE/ACM Transactions on Networking Computer Communication Review (by ACM SIGCOMM) Computer Communications Computer Networks and ISDN Systems IEICE Transactions on Communications Journal of High Speed Networks Magazines Communications Week/Internet Week Network World Data Communications Open Systems Today Lightwave (the leading-edge magazine for the fiber-optics industry) Industry News Letters ATM User, Published by Jefferies Research, contact info@atm-user.com The ATM Report, Published by Broadband Publishing Corporation. They can be contacted via email at 74551.1064@compuserve.com or by phone at 301-816-7858. --------------------------------------------------------------------------- SUBJECT C3) ATM information on the Internet A) Here's a list of sites that that seem to cater to the ATM/broadband/real-time continuous-media crowd: wuarchive.wustl.edu Research, ATM Hardware, Jon Turner papers ftp.tele.fi Standards drafts (see below) cell-relay.indiana.edu cell-relay archives, etc. (see below) info.bellcore.com Standards drafts, etc (see below) ftp.com21.com ip over atm work and related ATM Forum contributions can be found in ftp/pub/ip-atm B) Best of all (thanks to the Information Janitorial Staff :-) is the archive site for this list: the cell-relay retreat! This is a fairly specialized WEB site in that you'll find only information on cell-relay or broadband technologies (ATM/DQDB/SONET, etc.) including research papers, standards, product information, mailing list archives, and events such as conferences, workshops, etc. If this is what you're looking for, you're in the right place! If you have ftp access, ftp to cell-relay.indiana.edu as user anonymous and look in /pub/cell-relay for: archive Archives for the cell-relay newsgroup bib cell-relay bibliography conferences Upcoming conferences and call for papers related to cell-relay docs cell-relay research papers and standards vendors Vendor promotional materials publications Popular Books, Publications, Sources FAQ Containing this FAQ and other related FAQs of interest. C) Additionally, there are some draft standards, RFCs, technical papers, etc. on ATM available at ftp.tele.fi in the directory called /atm The collection includes draft AAL5 CCITT standards. This is a general good place to look. D) Similarly, at thumper.bellcore.com in the /pub/smq/ directory has some circa 1993 related ITU docs. E) Most ATM equipment vendors have WEB pages where they provide access to internally generated white papers on ATM and their own equipment. One of these is FORE at http://www.fore.com/atm-edu/ F) A lot of good papers, documents, and forum contributions may be found at Raj Jain's WEB pages at: http://www.cis.ohio-state.edu/~jain G) See also question subject A6 in this FAQ for pointers to *other* ATM related FAQ's. H) And don't forget to check the ATM Forum at: http://www.atmforum.com --------------------------------------------------------------------------- SUBJECT C4) How can I get the ATM Forum's Interface Specifications? The authoritative answer to this question can be found on the ATM Forum's WWW server in their Frequently Asked Questions document. These days most all of the ATM Forum's documents are online at their FTP site. * Web site: http://www.atmforum.com * anonymous ftp from ftp.atmforum.com See also question subject B5 in this FAQ. --------------------------------------------------------------------------- SUBJECT C5) List of ITU-T recommendations concerning ATM. This list is provided for informational purposes only. No guarantee as to its completeness or correctness. Also, although they are not formally published, many of the following recommendations have been substantially updated since first published. ITU-T Recommendations Concerning ATM * E.164 Numbering plan for the ISDN era 11/91 * G.707 Synchronous digital hierarchy bit rates 04/91 * G.708 Network node interface for the synchronous digital hierarchy 06/92 * G.709 Synchronous multiplexing structure 06/92 * I.113 B-ISDN Vocabulary of Terms 04/91 * I.121R Broadband Aspects Of ISDN 04/91 * I.150 B-ISDN asynchronous transfer mode functional characteristics 06/92 * I.211 B-ISDN service aspects 04/91 * I.311 B-ISDN General Network aspects 06/92 * I.321 B-ISDN protocol reference model and its application 04/91 * I.327 B-ISDN functional architecture 04/91 * I.361 B-ISDN ATM layer specification 06/92 * I.362 B-ISDN ATM adaptation layer (AAL) functional description 04/91 * I.363 B-ISDN ATM adaptation layer (AAL) specification (AAL1, AAL2, AAL3/4, AAL5) * I.413 B-ISDN user-network interface 04/91 * I.432 B-ISDN user-network interface - Physical layer specification 06/92 * I.610 OAM principles of the B-ISDN access 06/92 Also, there are draft recommendations yet to be published (or I am just not sure of their status): * I.35B BISDN ATM Layer Cell Transfer Performance, 1992 * I.364 Temp Doc 58 (XVIII) 'Support of Broadband Connectionless Data Service on B-ISDN' 06/92 * I.365.1 Frame Relaying Service Specific Convergence Sublayer (FR-SSCS) 06/93 * I.371 Temp Doc 64 (XVIII) 'Traffic Control and Congestion Control in B-ISDN' 05/92 * I.555 Frame Relaying Bearer Service Interworking 06/93 * Q.2931 B-ISDN User-Network Interface Layer 3 Specification for Basic Call/Bearer Control, 04/93 * Q.931 ISDN user-network interface layer 3 specification for basic call control 05/92 * Q.933 Digital Subscriber Signalling Systems No. 1 (DSS 1) Signalling Specification for Frame Mode Basic Call Control 05/92 * G.804 Which describes the mapping of ATM cells into PDH links at 1.544, 2.048, 6.312, 34.368, 44.736, 97.728, 139.264 Mb/s (Jan 1993) The following Q.SAAL documents are also germane: * Q.2100 "BISDN Signalling ATM Adaptation Layer Overview Description" * Q.2110 "BISDN Signalling ATM Adaptation Layer - Service Specific Connection Oriented Protocol (SSCOP) * Q.2130 "BISDN Signalling ATM Adaptation Layer - Service Specific Coordination Function for Support of Signalling at the User-to-Network Interface (SSCF at UNI)" And there are simply scads of BISDN Signalling draft Recommendations: * Q.2610 DSS2 & SS7 Use of cause and location in DSS2 and B-ISUP * Q.2650 DSS2 & SS7 Interworking of DSS2 and B-ISUP * Q.2660 SS7 Interworking of B-ISUP and Narrowband ISUP * Q.2730 SS7 Use of B-ISUP for Supplementary Services * Q.2761 SS7 Functional Description of B-ISUP * Q.2762 SS7 General Functions of B-ISUP messages and Parameters * Q.2763 SS7 B-ISUP Messages and Codes * Q.2764 SS7 B-ISUP Basic Call Procedures * Q.27BB SS7 B-ISUP for Point-to-Multipoint Calls * Q.27CC SS7 B-ISUP for Multiconnection Calls * Q.27DD SS7 Network Look-Ahead * Q.27EE SS7 B-ISUP Connection Modification * Q.27FF SS7 B-ISUP for Additional Traffic Types * Q.27GG SS7 B-ISUP Negotiation During Call Setup * Q.2931 DSS2 access signalling for BISDN * Q.2932 DSS2 generic functional protocol for supplementary svces * Q.2933 DSS2 signalling for interworking with frame relay * Q.293x DSS2 signalling overview document * Q.2951 DSS2 number identification supplementary svces * Q.2957 DSS2 additional information transfer supp svces * Q.2961 DSS2 traffic parameter negotiation capability * Q.2962 DSS2 bandwidth negotiation capability * Q.2963 DSS2 bandwidth modification capability * Q.2964 DSS2 Look Ahead feature * Q.2971 DSS2 point to multipoint control * Q.298x DSS2 multiconnection control * Q.29xx DSS2 multilevel priority capability --------------------------------------------------------------------------- SUBJECT C6) Internet drafts from IETF working groups. Early versions of the FAQ attempted to list current IETF drafts which are related to ATM. However the Internet Drafts change like sand running through your fingers. I recommend using the IETF URL listed below to surf the ID's yourself. Alternatively you can login via anonomyous FTP and search for key IETF working groups. Try *ROLC*, or *ATM*, or *ATOM*, or *IPATM*, or *ION*, etc. Internet Drafts are draft documents valid for a maximum of six months. Internet Drafts may be updated, replaced, or obsoleted by other documents at any time. It is not appropriate to use Internet Drafts as reference material or to cite them other than as a "working draft" or "work in progress". Please check the lid-abstracts.txt listing contained in the internet-drafts shadow directories on nic.ddn.mil, nic.nordu.net, ds.internic.net, or munnari.oz.au to learn the current status of any Internet Draft. Useful URL: http://ds.internic.net/ds/dspg0intdoc.html Internet-Drafts are available by anonymous FTP. Internet-Drafts directories are located (as officially designated by the IETF folks) at: * Africa Address: ftp.is.co.za (196.4.160.2) * Europe Address: nic.nordu.net (192.36.148.17) * Europe Address: ftp.nis.garr.it (192.12.192.10) * Pacific Rim Address: munnari.oz.au (128.250.1.21) * US East Coast Address: ds.internic.net (198.49.45.10) * US West Coast Address: ftp.isi.edu (128.9.0.32) Internet-Drafts are also available by mail. Send a message to: mailserv@ds.internic.net. In the body specify the filename requested. For example type: FILE /internet-drafts/draft-ietf-atmommib-atm-07.txt For questions on how to obtain Internet Drafts, please mail to Internet-Drafts@cnri.reston.va.us --------------------------------------------------------------------------- SUBJECT C7) ATM Tutorials. The following ATM tutorials are available via anonymous FTP. Running IP over ATM Machine: ftp.magic.net Path: /pub File: ip-atm.ps (PostScript) ip-atm.ps.Z (Compressed PostScript) The focus of this paper is running IP over ATM, but there is an extensive tutorial on ATM, followed by discussion IP over ATM networks. Anthony Alles' ATM Paper Machine: cell-relay.indiana.edu Path: /pub/cell-relay/docs/current File: ATM-Internetworking.* Where * equals one of the following file extensions: Compressed Postscript (.ps.Z) download using binary mode Adobe Acrobat (.pdf) download using binary mode Postscript (.ps) download using ascii mode Introduction to ATM (1993) Machine: ftp.tele.fi Path: atm/articles File: atm-intro.txt This paper is also a good starting point. "The Asynchronous Transfer Mode: A Tutorial" by Jean-Yves Le Boudec Computer Networks and ISDN, Vol 24, No 4, May 1992, pp 279-309 Access the ATM Forum on the World Wide Web at http://www.atmforum.com and then browse through the online info. The tutorial has some basic intro to ATM. Additionally there are reasonable tutorials available from several commercial communications companies. Specifically: 1. "Asynchronous Transfer Mode: Bandwidth for the Future", Jim Lane, Telco Systems, 1992. To order a free copy simply call 1-800-447-2537 2. "Broadband Testing Technologies", (a HP Seminar Handbook), Hewlett- Packard Company, February 1993, Document number 5091-6902E Call your local HP sales office and or contact the HP IDACOM Test division. The inside cover claims this document costs $10. 3. "Understanding ATM Networks", Bay Networks (SynOptics), part number 893-687-A. You can order it from SynOptics Press or a Bay Networks sales office. Additionally, Ameritech and the other Bell companies publish a pamphlet called "ATM Today" anad another called "SMDS Today". You can call (800) TEAM-DATA for copies. ATM Forum Ambassador Program ATM Forum has an ambassador program whereby they provide informative speakers to the networking community regarding various aspects of ATM. Ambassadors represent the ATM Forum and present ATM technology in a non vendor specific manner. Ambassadors can discuss firsthand current activities in the ATM Forum. Topics include: o Why ATM o Introduction to ATM o Intermediate ATM o ATM in the public WAN o Signalling 3.0 o Traffic Management 3.0 o B-ICI o Network Management o LAN Emulation Contact the ATM Forum for more information. Last but not least, Derek Hill has gathered together some on-line references in the teaching archive of his WWW server. It's designed for his students, not for ATM experts! http://www-ipg.umds.ac.uk/ (main server) http://www-ipg.umds.ac.uk/~dlgh/teaching/atmref.html (ATM references) Let him know (D.Hill@umds.ac.uk) if you have any comments or suggestions. --------------------------------------------------------------------------- SUBJECT C8) Contact information for ANSI T1S1 specifications. These documents can be obtained directly from the Secretariat for the ANSI T1 Telecommunications committee. Exchange Carriers Standard Association 1200 G. Street N.W. Suite 500 Washington, D.C. 20005 All orders and requests for quotations on prices must be in writing. Their FAX number is: (202) 393-5453 --------------------------------------------------------------------------- SUBJECT C9) Internet RFCs. The following RFCs are available related to cell-relay technology. * RFC 1483: Multiprotocol Encapsulation over ATM Adaptation Layer 5 * RFC 1577: Classical IP and ARP over ATM * RFC 1619: PPP over SONET/SDH * RFC 1626: Default IP MTU for use over ATM AAL5 * RFC 1680: IPng Support for ATM Services * RFC 1695: Definitions of Managed Objects for ATM Management * RFC 1735: NBMA Address Resolution Protocol (NARP) * RFC 1754: IP over ATM Working Group's Recommendations for the ATM Forum's Multiprotocol BOF Ver 1 * RFC 1755: ATM Signaling Support for IP over ATM * RFC 1821: Integration of Real-time Services in an IP-ATM Network Architecture * RFC 1926: An Experimental Encapsulation of IP Datagrams on Top of ATM * RFC 1932: IP over ATM: A Framework Document * RFC 1946: Native ATM Support for ST2+ * RFC 1954: Ipsilon approach for IP over ATM * RFC 2022: Support for Multicast over UNI 3.0/3.1 based ATM Networks * RFC 2098: Toshiba's Cell Stream Router * RFC 2105: Cisco's Tag Switching * RFC 2121: Issues affecting MARS cluster size * RFC 2129: More Toshiba specifications * RFC 2170: Application Requested IP over ATM * RFC 2191: VENUS - Very Extensive non-unicast Service Details on obtaining RFCs via FTP or EMAIL may be obtained by sending an EMAIL message to rfc-info@ISI.EDU with the message body help: ways_to_get_rfcs. For example: To: rfc-info@ISI.EDU Subject: getting rfcs help: ways_to_get_rfcs On the WEB try the following: http://ds.internic.net/ds/dspg0intdoc.html --------------------------------------------------------------------------- SUBJECT C10) ATM and Related Acronyms. The cell-relay archives contain an ever growing list of acronyms which tend to appear in postings, RFCs, standards and other text related to the cell-relay topic area. This list is at http://cell-relay.indiana.edu/cell-relay/FAQ/ATM-Acronyms.html Here are a few five dollar words which sometime arise in this topic area. * Plesiochronous: Signals which are arbitrarily close in frequency to some defined precision. They are not sourced from the same clock and so, over the long term, will be skewed from each other. Their relative closeness of allows a switch to cross connect, switch, or in some way processs them. That same inaccuracy of timing will force a switch, over time, to repeat or delete frames (called frame slips) in order to handle buffer underflow or overflow. * Synchronous: Signals that are sourced from the same timing reference. These have the same frequency. (Contrast with Plesiochronous signals.) Typically for synchronous data interfaces there will be a separate clock signal and the data need not be clocked at a uniform rate. * Asynchronous: Signals that are sourced from independent clocks. These signals generally have no relation to each other and so have different frequencies and phase relationships. (Contrast with Plesiochronous signals.) * Isochronous: Signals which are dependant on some uniform timing or carry their own timing information embedded as part of the signal. So isochronous data signals can be thought of as being "self-clocked". That is there is no spatially separate clock signal. A receiver would extract the uniform bit-rate clock from the actual data stream. Thus the two ends of a connection would run on the same clock, extracting data at a fixed (smooth) rate. (Contrast with Synchronous signals.) --------------------------------------------------------------------------- SUBJECT C11) Literature and papers on the self-similar (fractal) property of traffic? The volume of literature on self-similar data traffic is huge. Here are some of the best and each of these has lots of other references. [1] is one of the most important networking papers of the decade and launched this new examination of data traffic performance. [2], from the same authors, is an informal discussion of the importance of self-similar traffic modeling. [3] provides a solid analysis of TCP-based self-similar traffic and includes a number of useful appendices on underlying mathematical concepts of general interest in self-similar traffic modeling. [4] focuses on the impact of self-similarity on queuing performance and provides a good overview of the issues and modeling techniques involved. [1] Leland, W.; Taqqu, M.; Willinger, W.; and Wilson, D. "On the Self-Similar Nature of Ethernet Traffic (Extended Version)." IEEE/ACM Transactions on Networking, February 1994. [2] Willinger, W.; Wilson, D.; Wilson, D.; and Taqqu, M. "Self-Similar Traffic Modeling for High-Speed Networks." ConneXions, November 1994. [3] Paxson, V., and Floyd, S. "Wide Area Traffic: The Failure of Poisson Modeling." IEEE/ACM Transactions on Networking, June 1995. [4] Erramilli, A.; Narayan, O.; and Willinger, W. "Experimental Queueing Analysis with Long-Range Dependent Packet Traffic." IEEE/ACM Transactions on Networking, April 1996. The first paper listed above [1] was originally published in sigcomm93 as a shorter paper. This and the longer version was the work which started the whole self-similar perspective. The original sigcomm93 version can be found online at: ftp://ftp.bellcore.com/pub/world/wel/sigcomm93.ps.Z The updated longer version [1] appeared in IEEE/ACM Trans. on Networking (and won IEEE's highest award for a research paper). It is on-line as ftp://ftp.bellcore.com/pub/wel/world.tome.ps.Z The author asks that you read the README: ftp://ftp.bellcore.com/pub/world/wel/README This is also available in Adobe Acrobat for Mac/Windows folks (also Sun Solaris and 4.1.3). It is be available as a link on: http://cell-relay.indiana.edu/cell-relay/docs/TechReports.html At SIGCOMM '94, Mark Garrett and others showed that MPEG is self-similar ftp://ftp.bellcore.com/pub/dvw/sigcomm94mwg.ps There have been several more papers (generally in ACM SIGCOMM proceedings) show WAN traffic is self-similar and beginning to explore reasons why traffic might be self-similar. NOTE: If you have problems accessing any FTP sites through your WEB browser, try using a normal FTP application and log on with a user name of "anonomous", and supply your email address as a password. --------------------------------------------------------------------------- SUBJECT C12) How can I get copies of ITU-T documents? You can buy these on paper from the ITU: ITU Place des Nations CH-1211 Geneva 20 Switzerland. The fax number of the sales office is +41 22 730 5194. They also have an online publications services which is available by subscription. See their FAQ at http://www.itu.int/publications for more information. Through their service you can get documents at http://www.itu.ch/itudoc/itu-t/rec/q.html. If you are not a subscriber you can send mail to sales@itu.ch to order a paper copy. It is also possible to get access to ITU documents available for downloading on the Web without a subscription. You can pay for a single document with a credit card. Refer to http://www.itu.int/publications for more details. They are also available commercially from at least 3 sources in the US: * Information Gatekeepers in Boston, MA (1-800-323-1088) * Phillips Publishing (1-800-OMNICOM) * Global Engineering Documents (1-800-854-7179) Phillips usually has documents in stock & has fast delivery. General online access is limited. Some postings suggested telnet to: ties.itu.ch / 156.106.4.75 or chi.itu.ch / 156.106.4.16 Some postings suggested the IMTC web site at http://www.imtc.org/. They have most of the relevant H series and T series drafts available online, plus some useful overview/tutorial stuff. Others suggest using gopher because that is what they are using. For gopher you'll need to use info.itu.ch if you want to use a local gopher client. Click on the link in the last sentence to connect to info.itu.ch. ties and chi will refuse connections to port 70. Some can be accessed on http://www.itu.ch/ (ITU World Wide Web site). You can also get copies of ITU documents using their auto-answering mailbox. Send mail to itudoc@itu.ch with: GET ITU-4313 in the message body to get information how to get the documents, including I.363, that you want. Alternatively, send e-mail to itudoc@itu.ch with the single line HELP in the body of the message. That will get you information on the ITU's automatic mail server. Essentially you send a message to the above address with: GET ITU-nnnn in the body, where nnnn is the document identifier number that you get by asking for ITU-1100, which is the index to the ITU I. series, including I.363. ITU-4313 also has directions how to use gopher: Name=3DInternational Telecommunications Union (ITU) Host=3Dinfo.itu.ch Port=3D70 For a while there were many ITU documents available electronically. However sometime in 1995 the ITU has taken these off line and they are no longer readily available. If you have access to a cdrom (and an pc/mac) there is a "Standard's" cdrom from Infomagic available for $30.00. This provides all of the ITU documents which had been online as well as IETF documents. The ITU documents include those published since 1988 (when they became available electronically) through this summer. A few are missing (i.e. X.741). Almost all of these recomendations are in postscript format, so you will also need a viewer (ghostscript and ghost view are on the disks). InfoMagic may be contacted at: Tel: +1-520-526-9565 Fax: +1-520-526-9573 E-mail: info@infomagic.com Web: www@infomagic.com InfoMagic 11950 N. Highway 89 Flagstaff, Ax 86004 Finally, don't forget to try the various Internet hosts on which ITU drafts and other goodies may be found. A good place to start is ftp.tele.fi or info.bellcore.com, check subject C3 of this FAQ for additional information. ---------------------------------------------------------------------------