frith@trwrdc.UUCP (Lord Frith) (10/07/85)
Please be patient. Communications is not my strong suit... Right now I'm involved in a project that will network several machines together using TCP/IP and X.25 protocols. Can anyone tell me where I might find specs detailing the ues of the following protocol standards... UDP User Datagram Protocol RFC 768 Packet standard of some sort? X.25 Where can one obtain specs for this? Arpanet 1822 Any relation to TCP/IP? And what is this new NBS TP-4 protocol? I also hear there is a new internetwork protocol coming? -- seismo!trwrdc!root - Lord Frith "And I want you" "And I want you" "And I want you so" "It's an obsession"
fair@ucbarpa.berkeley.edu (Erik E. Fair) (10/09/85)
In article <1062@trwrdc.UUCP> frith@trwatf.UUCP (Lord Frith) writes: > >Right now I'm involved in a project that will network several >machines together using TCP/IP and X.25 protocols. Can anyone >tell me where I might find specs detailing the ues of the following >protocol standards... > >UDP User Datagram Protocol >RFC 768 Packet standard of some sort? >X.25 Where can one obtain specs for this? >Arpanet 1822 Any relation to TCP/IP? > >And what is this new NBS TP-4 protocol? I also hear there is >a new internetwork protocol coming? RFC768 is `Request For Comments' #768, and it is the specification document for UDP, the User Datagram Protocol, which is one of a suite of protocols that are implemented on the ARPA Internet. The other immediately relevant documents are: RFC791 - Internet Protocol (IP) RFC792 - Internet Control Message Protocol (ICMP) RFC793 - Transmission Control Protocol (TCP) RFC904 - Exterior Gateway Protocol (EGP) RFC943 - Assigned Numbers RFC944 - Official Protocols This list is not exhaustive; RFC944 contains pointers to other documentation and protocol specifications. Both RFC943 and RFC944 are the current versions of the `Assigned Numbers' and `Official Protocols' lists, however, they are updated with reasonable regularity, so you should be sure to ask for the latest copy of each. BBN Report 1822 is the hardware and software specification for the Host-IMP interface in the ARPA Internet. You can think of it being equivalent to the Ethernet LAN specification. All of the documents that I mention here are available in hardcopy from Network Information Center Telecommunications Sciences Center SRI International 333 Ravenswood Avenue Menlo Park, CA 94025 They can also be fetched in electronic form by sites that are on the ARPA Internet from SRI-NIC.ARPA (The Network Information Center). The NIC staff is reachable at NIC@SRI-NIC.ARPA. 4.2 BSD (Berkeley UNIX) comes with a complete implementation of the IP/TCP protocols, and many companies have used this as a base to get into networking quickly, be they in hardware (e.g. CMC, Exelan) or software (e.g. UniSoft, The Wollongong Group). I hope this helps, Erik E. Fair ucbvax!fair fair@ucbarpa.BERKELEY.EDU P.S. For further edification on the subject of ISO/CCITT vs. ARPA Internet, read The Elements of Networking Style M. A. Padlipsky ISBN 0-13-268129-3 01 Prentice-Hall, Inc., Englewood Cliffs, NJ 07632 Published in 1985
jr@bbncc5.UUCP (John Robinson) (10/11/85)
X.25 is a widely-used network interface standard promulgated by the CCITT, a part of the International Telephone Union (Telegraph maybe?), which is itself a UN body. Copies of it are widely available. One place that will be happy to sell you one is: Omnicom Inc. Suite 206, 501 Church St. NE Vienna, VA 22180 703-281-1135 The current version is dated 1980; the 1984 version is imminent, thoughthe differences won't be material until the DDN (DoD networks) implement it which will be maybe a year; the differences are minor and mostly extensions you won't need. In the DDN, X25 is a host access link protocol available as an alternate to 1822 (which is not used very much outside the DoD). DoD network hosts are expected to use TCP and IP, for which specs are available from the NIC as previously stated. Hosts using X25 to access the DDN need to know how to encapsulate IP datagrams inside X.25 messages; this is covered in BBN report 5476. This follows the guidelines originated in RFC 877 from the NIC. It also refers to FIPS (Federal Information Processing Standard) 100, which standardizes the use of X25 in US Government networks (and is included in report 5476). For the BBN report and matters relating to the DDN, you should work through: Defense Communications Agency ATTN: DDN Program Management Office Code B610 Washington DC 20305 I will be happy to field (brief) technical questions about how these standards relate to each other on the DDN; please send mail because I don't read this newsgroup too regularly. Another comment on the datagram-vs-VC battle - X25 and 1822 will really become essentially equal methods of accessing the DDN by about fall 1986. Although 1822 seems to present a datagram interface, in reality the network builds virtual circuits on behalf of hosts anyway and always has. The hosts' control over these VCs is only indirect; 1822 implementors know about "RFNM-counting". X25 allows hosts to control the setup and teardown of VCs in the network explicitly, which can result in lower network overhead if the host is smart; gateways in particular ought to be able to take advantage of this to provide better flow control back to specific hosts and avoid much of the packet loss seen today (by hosts sending to gateways over long-haul networks). Well, I could go on but won't... /jr