Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!ucsd!ucbvax!UDEL.EDU!Mills From: Mills@UDEL.EDU Newsgroups: comp.protocols.tcp-ip Subject: Re: Running out of Internet addresses? Message-ID: <8812061258.aa12359@Huey.UDEL.EDU> Date: 6 Dec 88 17:58:22 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 22 Vint, You may have heard me honk this subject before, but my feeling is to byte the bullet and adopt variable-length type-E addresses and encode them as per ISO NSAP. From my implementation esperience variable-length addresses are maybe a little awkward, but not really hard when compared to variable-length options, etc. The ISO NSAP addressing format includes a length/format identifier, so it is in principle possible to adopt this format, even if the format is not completely decoded by all gateways, by teaching the header-parser code how to leapfrog the address field in order to parse the options. The big win in my view is the possibility of carrying additional baggage, such as authority, policy and so forth encoded in the address field (perhaps in the IDP field). In my opinion we should face this issue squarely and right now. A statement like: in the future the Internet may be forced to adopt variable-length addressing. If so, it will be expressed in an ISO encoding as a type E format (at least the high-order three bits). Host and gateway implementors should bear this in mind as they implement header-parsing algorithms and data structures. Or something like that. Dave