ARPANET 1822L Host Access Protocol
RFC 851
Document | Type |
RFC - Unknown
(April 1983; No errata)
Obsoleted by RFC 878
Obsoletes RFC 802
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Last updated | 2013-03-02 | ||
Stream | Legacy | ||
Formats | plain text html pdf htmlized bibtex | ||
Stream | Legacy state | (None) | |
Consensus Boilerplate | Unknown | ||
RFC Editor Note | (None) | ||
IESG | IESG state | RFC 851 (Unknown) | |
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Responsible AD | (None) | ||
Send notices to | (None) |
Request for Comments: 851 Obsoletes RFC: 802 The ARPANET 1822L Host Access Protocol RFC 851 Andrew G. Malis ARPANET Mail: malis@bbn-unix Bolt Beranek and Newman Inc. 50 Moulton St. Cambridge, MA 02238 April 1983 This RFC specifies the ARPANET 1822L Host Access Protocol, which is a successor to the existing 1822 Host Access Protocol. 1822L allows ARPANET hosts to use logical names as well as 1822's physical port locations to address each other. The RFC is also being presented as a solicitation of comments on 1822L, especially from host network software implementers and maintainers. 1822L Host Access Protocol April 1983 RFC 851 Table of Contents 1 INTRODUCTION.......................................... 1 2 THE ARPANET 1822L HOST ACCESS PROTOCOL................ 4 2.1 Addresses and Names................................. 6 2.2 Name Translations................................... 8 2.2.1 Authorization and Effectiveness................... 8 2.2.2 Translation Policies............................. 11 2.2.3 Reporting Destination Host Downs................. 13 2.2.4 1822L and 1822 Interoperability.................. 16 2.3 Uncontrolled Packets............................... 18 2.4 Establishing Host-IMP Communications............... 20 2.5 Counting RFMS When Using 1822L..................... 22 2.6 1822L Name Server.................................. 24 3 1822L LEADER FORMATS................................. 27 3.1 Host-to-IMP 1822L Leader Format.................... 28 3.2 IMP-to-Host 1822L Leader Format.................... 35 4 REFERENCES........................................... 43 - i - 1822L Host Access Protocol April 1983 RFC 851 FIGURES 1822 Address Format....................................... 6 1822L Name Format......................................... 7 1822L Address Format...................................... 7 Communications between different host types.............. 17 Host-to-IMP 1822L Leader Format.......................... 28 NDM Message Format....................................... 31 IMP-to-Host 1822L Leader Format.......................... 35 Name Server Reply Format................................. 39 - ii - 1822L Host Access Protocol April 1983 RFC 851 1 INTRODUCTION This RFC specifies the ARPANET 1822L Host Access Protocol, which will allow hosts to use logical addressing (i.e., host names that are independent of their physical location on the ARPANET) to communicate with each other. This new host access protocol is known as the ARPANET 1822L (for Logical) Host Access Protocol, and is a successor to the current ARPANET 1822 Host Access Protocol, which is described in sections 3.3 and 3.4 of BBN Report 1822 [1]. Although the 1822L protocol uses different Host-IMP leaders than the 1822 protocol, the IMPs will continue to support the 1822 protocol, and hosts using either protocol can readily communicate with each other (the IMPs will handle the translation automatically). There is one major restriction to the new 1822L protocol: it will be implemented in C/30 IMPs only, and will therefore only be usable by hosts connected to C/30 IMPs, as Honeywell and Pluribus IMPs do not have sufficient memory to hold the new programs and tables. This restriction also means that logical addressing cannot be used to identify a host on a non-C/30 IMP. While this is not a problem on the ARPANET, which only has C/30 IMPs, the restriction will apply if logical addressing is used on any network that mixes C/30 and non-C/30 IMPs. - 1 - 1822L Host Access Protocol April 1983 RFC 851 The RFC's terminology is consistent with that used in Report 1822, and any new terms will be defined when they are first used. Familiarity with Report 1822 (section 3 in particular) is assumed. As could be expected, the RFC makes many references to Report 1822. As a result, it uses, as a convenient abbreviation, "see 1822(x)" instead of "please refer to Report 1822, section x,Show full document text