Path: utzoo!attcan!uunet!decwrl!ucbvax!VAX.FTP.COM!jbvb From: jbvb@VAX.FTP.COM (James Van Bokkelen) Newsgroups: comp.protocols.tcp-ip Subject: Re: What Size IP on TR? Message-ID: <9007021410.AA05022@vax.ftp.com> Date: 2 Jul 90 14:10:09 GMT References: <9006292303.AA06091@vax.ftp.com> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 20 Date: Fri, 29 Jun 90 15:41 PDT From: Michael Stein An example is a RIF which says 2052 where there are routers to Ethernet (max IP packet size of 1500). Any IP packet larger than 1500 will get fragmented. Most modern TCP implementations have Maximum Segment Size option handling which attempts to avoid fragmentation when traversing routers. If the transport protocol you're concerned with is layered on UDP, you are likely to find that you must tweak things manually. At any rate, what I was saying was that there was a time when you *had* to say "2052" in your RIF, or some IBM TCP/IP implementations wouldn't talk to you at all. Thus, you are likely to find that as a widely-used default... James B. VanBokkelen 26 Princess St., Wakefield, MA 01880 FTP Software Inc. voice: (617) 246-0900 fax: (617) 246-0901