From owner-freebsd-tokenring Tue Apr 21 15:19:02 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id PAA09796 for freebsd-tokenring-outgoing; Tue, 21 Apr 1998 15:19:02 -0700 (PDT) (envelope-from owner-freebsd-tokenring@FreeBSD.ORG) Received: from heathers2.stdio.com (lile@heathers2.stdio.com [199.89.192.5]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id WAA09632 for ; Tue, 21 Apr 1998 22:18:19 GMT (envelope-from lile@stdio.com) Received: (from lile@localhost) by heathers2.stdio.com (8.8.8/8.8.8) id SAA15303; Tue, 21 Apr 1998 18:15:19 -0400 (EDT) Date: Tue, 21 Apr 1998 18:15:18 -0400 (EDT) From: "Larry S. Lile" To: Paul Norton cc: tokenring@FreeBSD.ORG Subject: Re: Current work... In-Reply-To: <199804212055.NAA01835@grumpy.ccnvhi.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-tokenring@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 21 Apr 1998, Paul Norton wrote: > Matthew N. Dodd writes: > > We need to set our min and max based on line speed and let the user adjust > > to some value between if they desire. Min will probably be the same for > > both. > > Max MTU is a function of ring speed and configured shared-RAM for the 16/4 > adapters. There's a draft IETF standard that recommends 1500 as > default. > > > Also remember that all our data rides around in 802.2 packets so we have > > those headers to deal with as well. > > Max IP MTU = Recv. buf size - 802.5 MAC header including max possible RIF > - 802.2 header - SNAP header. > All the AIX boxen I admin run a MTU of 1492 on their token ring interfaces, any clue at to the 8 byte diff? Were basically going to need a /usr/src/sys/net/iso88025.h which would contain: #define ISO88025_ADDR_LEN 6 #define ISO88025_TYPE_LEN 2 /* Assumed */ #define ISO88025_CRC_LEN 4 /* Assumed */ #define ISO88025_HDR_LEN (ISO88025_ADDR_LEN*2+ISO88025_LEN) /* +RIF? */ #define ISO88025_MIN_LEN x /* No clue */ #define ISO88025_MAX_LEN 1518 /* Assumed same as ethernet */ #define ISO88025_IS_VALID_LEN(foo) \ ((foo) >= ISO88025_MIN_LEN && (foo) <= ISO88025_MAX_LEN) /* This may be over-kill ? */ struct iso88025_header { u_char iso88025_dhost[ISO88025_ADDR_LEN]; u_char iso88025_shost[ISO88025_ADDR_LEN]; u_short ether_type; /* RIF? */ }; struct iso88025_addr { u_char octet[ISO88025_ADDR_LEN]; }; Any ideas, suggestions or correct numbers to fill in? or should we just kludge through the ether subsystem? Larry lile@stdio.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-tokenring" in the body of the message