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diff --git a/share/man/man4/esis.4 b/share/man/man4/esis.4 new file mode 100644 index 00000000000..84cf4c42e20 --- /dev/null +++ b/share/man/man4/esis.4 @@ -0,0 +1,217 @@ +.\" $NetBSD: esis.4,v 1.3 1994/11/30 16:22:12 jtc Exp $ +.\" +.\" Copyright (c) 1990, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)esis.4 8.2 (Berkeley) 11/30/93 +.\" +.Dd November 30, 1993 +.Dt ESIS 4 +.Os +.Sh NAME +.Nm es-is +.Nd End System to Intermediate System Routing Protocol +.Sh SYNOPSIS +.Sy pseudo-device +.Nm ether +.Sh DESCRIPTION +The +.Nm ES-IS +routing protocol is used to dynamically map between +.Tn ISO NSAP +addresses and +.Tn ISO SNPA +addresses; to permit End and Intermediate Systems +to learn of each other's existence; and to allow Intermediate Systems +to inform End Systems of (potentially) better routes to use when +forwarding +.Tn NPDU Ns s +to a particular destination. +.Pp +The mapping between +.Tn NSAP +addresses and +.Tn SNPA +addresses is accomplished by +transmitting hello +.Tn PDU Ns s +between the cooperating Systems. These +.Tn PDU Ns s +are transmitted whenever the +.Em configuration +timer expires. +When a hello +.Tn PDU +is received, the +.Tn SNPA +address that it conveys is stored in the routing table for as long as the +.Em holding time +in the +.Tn PDU +suggests. The default +.Em holding time +(120 seconds) placed in the hello +.Tn PDU , +the configuration timer value, +and the system type (End System or Intermediate System) may be changed by +issuing an +.Dv SIOCSSTYPE +.Xr ioctl 2 , +which is defined in +.Pa /sys/netiso/iso_snpac.h. +.Pp +The protocol behaves differently depending on whether the System is +configured as an End System or an Intermediate System. +.Sh END SYSTEM OPERATION +When an interface requests a mapping for an address not in the cache, +the +.Tn SNPA +of any known Intermediate System is returned. If an Intermediate +System is not known, then the +.Em all end systems +multicast address +is returned. It is assumed that the intended recipient of the NPDU will +immediately transmit a hello +.Tn PDU +back to the originator of the +.Tn NPDU . +.Pp +If an +.Tn NPDU +is forwarded by the End System, a redirect +.Tn PDU +will not be +generated. +However, redirect +.Tn PDU Ns s +received will be processed. This processing +consists of adding an entry in the routing table. If the +redirect is towards an Intermediate System, then an entry is made in the +routing table as well. +The entry in the routing table will mark the +.Tn NSAP +address contained in the redirect +.Tn PDU +as the gateway for the destination +system (if an NET is supplied), or will create a route with +the NSAP address as the +destination and the +.Tn SNPA +address (embodied as a link-level sockaddr) as the +gateway. +.Pp +If the System is configured as an End System, it will report all the +.Tn NSAP Ns s +that have been configured using the ifconfig command, and no others. +It is possible to have more than one +.Tn NSAP +assigned to a given interface, +and it is also possible to have the same +.Tn NSAP +assigned to multiple +interfaces. +However, any +.Tn NSAP +containing an NSEL that is consistent with the +nsellength option (default one) of any interface will be accepted as +an +.Tn NSAP +for this System. +.Sh INTERMEDIATE SYSTEM OPERATION +When an interface requests a mapping for an address not in the routing table, +an error is returned. +.Pp +When an +.Tn NPDU +is forwarded out on the same interface that the +.Tn NPDU +arrived upon, +a redirect +.Tn PDU +is generated. +.Sh MANUAL ROUTING TABLE MODIFICATION +.Pp +To facilitate communications with systems which do not use +.Nm ES-IS, +one may add a route whose destination is a sockaddr_iso containing +the +.Tn NSAP +in question, and the gateway being a link-level sockaddr, +either by writing a special purpose program, or using the +.Xr route 8 +command e.g.: +.Bd -literal +route add -iface -osi 49.0.4.8.0.2b.b.83.bf \ + -link qe0:8.0.2b.b.83.bf +.Ed +.Pp +If the +System is configured as an End System and has a single network interface +which does not support multicast reception, +it is necessary to manually configure the location of an +.Tn IS , +using the route command in a similar way. +There, the destination address should be +.Dq default +(spelled +out literally as 7 +.Tn ASCII +characters), and the gateway should be +once again be a link-level sockaddr specifying the +.Tn SNPA +of the +.Tn IS . +.Sh SEE ALSO +.Xr un 4 , +.Xr iso 4 , +.Xr route 8 , +.Xr ifconfig 8 +.Rs +.%T "End system to Intermediate system routing exchange protocol for use in conjunction with the Protocol for providing the connectionless-mode network service" +.%R ISO +.%N 9542 +.Re +.Sh BUGS +Redirect +.Tn PDU Ns s +do not contain options from the forwarded +.Tn NPDU +which generated +the redirect. The multicast address used on the 802.3 network is taken from +the +.Tn NBS +December 1987 agreements. This multicast address is not compatible +with the 802.5 (Token Ring) multicast addresses format. Therefore, broadcast +addresses are used on the 802.5 subnetwork. +Researchers at the University of Wisconsin are constructing an implementation +of the +.Tn IS-IS +routing protocol. |