Return to esis.4 CVS log

Up to [CSRG BSD Unix] / 43BSDReno / share / man / man4

Annotation of 43BSDReno/share/man/man4/esis.4, revision 1.1

1.1     ! root        1: .\" Copyright (c) 1990 The Regents of the University of California.
        !             2: .\" All rights reserved.
        !             3: .\"
        !             4: .\" Redistribution and use in source and binary forms are permitted provided
        !             5: .\" that: (1) source distributions retain this entire copyright notice and
        !             6: .\" comment, and (2) distributions including binaries display the following
        !             7: .\" acknowledgement:  ``This product includes software developed by the
        !             8: .\" University of California, Berkeley and its contributors'' in the
        !             9: .\" documentation or other materials provided with the distribution and in
        !            10: .\" all advertising materials mentioning features or use of this software.
        !            11: .\" Neither the name of the University nor the names of its contributors may
        !            12: .\" be used to endorse or promote products derived from this software without
        !            13: .\" specific prior written permission.
        !            14: .\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
        !            15: .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
        !            16: .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
        !            17: .\"
        !            18: .\"    @(#)esis.4      6.1 (Berkeley) 7/25/90
        !            19: .\"
        !            20: .TH TP 4 "July 25, 1990"
        !            21: .UC 5
        !            22: .SH NAME
        !            23: es-is \- End System to Intermediate System Routing Protocol
        !            24: .SH SYNOPSIS
        !            25: .B "pseudo-device ether"
        !            26: .SH DESCRIPTION
        !            27: The ES-IS routing protocol is used to dynamically map between ISO NSAP
        !            28: addresses and ISO SNPA addresses; to permit End and Intermediate Systems
        !            29: to learn of each other's existence; and to allow Intermediate Systems
        !            30: to inform End Systems of (potentially) better routes to use when 
        !            31: forwarding NPDUs to a particular destination.
        !            32: .PP
        !            33: The mapping between NSAP addresses and SNPA addresses is accomplished by
        !            34: transmitting hello PDUs between the cooperating Systems. These PDUs
        !            35: are transmitted whenever the \fIconfiguration\fR timer expires.
        !            36: When a hello PDU is received, the SNPA
        !            37: address that it conveys is stored in the routing table for as long as the
        !            38: \fIholding time\fR in the PDU suggests. The default \fIholding time\fR
        !            39: (120 seconds) placed in the hello PDU, the configuration timer value,
        !            40: and the system type (End System or Intermediate System) may be changed by
        !            41: issuing an SIOCSSTYPE ioctl(), which is defined in /sys/netiso/iso_snpac.h.
        !            42: .PP
        !            43: The protocol behaves differently depending on whether the System is
        !            44: configured as an End System or an Intermediate System.
        !            45: .SH "END SYSTEM OPERATION"
        !            46: When an interface requests a mapping for an address not in the cache,
        !            47: the SNPA of any known Intermediate System is returned. If an Intermediate
        !            48: System is not known, then the \fIall end systems\fR multicast address
        !            49: is returned. It is assumed that the intended recipient of the NPDU will
        !            50: immediately transmit a hello PDU back to the originator of the NPDU.
        !            51: .PP
        !            52: If an NPDU is forwarded by the End System, a redirect PDU will not be
        !            53: generated.
        !            54: However, redirect PDUs received will be processed. This processing
        !            55: consists of adding an entry in the routing table. If the
        !            56: redirect is towards an Intermediate System, then an entry is made in the
        !            57: routing table as well.
        !            58: The entry in the routing table will may mark the
        !            59: NSAP address contained in the redirect PDU as the gateway for the destination
        !            60: system (if an NET is supplied), or will create a route with
        !            61: the NSAP address as the
        !            62: destination and the SNPA address (embodied as a link-level sockaddr) as the
        !            63: gateway.
        !            64: .PP
        !            65: If the System is configured as an End System, it will report all the
        !            66: NSAPs that have been configured using the ifconfig command, and no others.
        !            67: It is possible to have more than one NSAP assigned to a given interface,
        !            68: and it is also possible to have the same NSAP assigned to multiple
        !            69: interfaces.
        !            70: However, any NSAP containing an NSEL that is consistent with the
        !            71: nsellength option (default one) of any interface will be accepted as
        !            72: an NSAP for this System.
        !            73: .SH "INTERMEDIATE SYSTEM OPERATION"
        !            74: When an interface requests a mapping for an address not in the routing table,
        !            75: an error is returned.
        !            76: .PP
        !            77: When an NPDU is forwarded out on the same interface that the NPDU arrived upon,
        !            78: a redirect PDU is generated.
        !            79: .SH "MANUAL ROUTING TABLE MODIFICATION"
        !            80: .PP
        !            81: To facilitate communications with systems which do not use ES-IS,
        !            82: one may add a route whose destination is a sockaddr_iso containing
        !            83: the NSAP in question, and the gateway being a link-level sockaddr,
        !            84: either by writing a special purpose program, or using the
        !            85: .IR route (8)
        !            86: command e.g.:
        !            87: .nf
        !            88: 
        !            89:        route add -iface -osi 49.0.4.8.0.2b.b.83.bf -link qe0:8.0.2b.b.83.bf
        !            90: .fi
        !            91: .PP
        !            92: If the
        !            93: System is configured as an End System and has a single network interface
        !            94: which does not support multicast reception,
        !            95: it is necessary to manually configure the location of an IS,
        !            96: using the route command in a similar way.
        !            97: There, the destination address should be ``default'' (spelled 
        !            98: out literally as 7 ascii characters), and the gateway should be
        !            99: once again be a link-level sockaddr specifying the SNPA of the IS.
        !           100: .SH SEE ALSO
        !           101: un(4), iso(4F), route(8), ifconfig(8C)
        !           102: .br
        !           103: ``End system to Intermediate system routing exchange protocol
        !           104: for use in conjunction with the Protocol for providing the 
        !           105: connectionless-mode network service'' (ISO 9542).
        !           106: .SH BUGS
        !           107: Redirect PDUs do not contain options from the forwarded NPDU which generated
        !           108: the redirect. The multicast address used on the 802.3 network is taken from
        !           109: the NBS December 1987 agreements. This multicast address is not compatible
        !           110: with the 802.5 (Token Ring) multicast addresses format. Therefore, broadcast
        !           111: addresses are used on the 802.5 subnetwork.
        !           112: Researchers at the University of Wisconsin are constructing an implementation
        !           113: of the IS-IS routing protocol.

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.