Path: utzoo!utgpu!watmath!clyde!att!rutgers!mit-eddie!bu-cs!mirror!frog!cpoint!martillo From: martillo@cpoint.UUCP (martillo) Newsgroups: comp.protocols.tcp-ip Subject: Re: TCP/IP over FDDI Message-ID: <1413@cpoint.UUCP> Date: 5 Dec 88 08:28:00 GMT References: <21741@sgi.SGI.COM>Reply-To: martillo@cpoint.UUCP (martillo) Organization: Clearpoint Research Corp., Hopkinton Mass. Lines: 24 The mac-header size seems really perverted but isn't this issue really larger than just choosing a disgusting header size. Why do mac level addresses have to be so large? Why does each card have to have a unique mac address (not just for FDDI but apparently for the who 802.x technologies). IP or IP equivalent addresses need to be unique. But making physical layer addresses unique for the known universe is a waste of time. Better to have some authority on a given lan which assigns the locally significant mac layer addresses. Then 2 bytes would be sufficient. How many lans have more than 64k hosts on them? The real problem is that the IEEE with total misunderstanding views 802.2 which is a communications subnet protocol as an end-to-end protocol. To make the problem worse, 802.2 type 2 is based on LAPB which is a communications subnet access protocol. FDDI has added complexity because the FDDI committee refuses to accept that host with a dual mac FDDI controller is really attached to two separate physical networks and not one physical network (at least as I understand the current proposals). Joachim Carlo Santos Martillo