ccc_ldo@waikato.ac.nz (Lawrence D'Oliveiro, Waikato University) (07/12/90)
I don't know if this issue has come up before, but here goes... A suggestion was made to me recently (only half-serious so far) about doing wide-area AppleTalk routing between our varsity and others in New Zealand. As the campus administrator of AppleTalk nets, my immediate response was "no way!". I was thinking of all the hassles that everybody would have to go through to work out allocations of the AppleTalk network numbering space, and the amount of reconfiguring of existing AppleTalk routers (Multigates, FastPaths etc) that would probably be necessary to implement this. It seems to me a solution is possible, by adding suitable software to the wide-area AppleTalk routers, to do "network number aliasing". What this means is that, on my site, I allocate a chunk of network numbers, say 49152 to 65279, which I haven't used for my local nets. The AppleTalk router connecting my site to the rest of the world then maps any network numbers it sees on the other side into this range. The same sort of thing happens at other sites. Naturally this reserved range must be reconfigurable, depending on how I've been allocating the network numbers locally, and on how many nets I expect to see "out there". Perhaps an example will make things clearer. Consider sites A and B, each of which has numbered their AppleTalk nets starting from 1. Say site A has networks numbered 1, 2 and 3, and similarly for site B. No way you can connect a standard AppleTalk router directly between these two sites, right? Supposing each site has a "wide-area" router connecting it to the rest of the world. The one connecting site A will tell the rest of the world about nets 1, 2 and 3, and their zone names, and similarly the one at site B. The information that each router *receives* from the rest of the world, however, gets remapped into the reserved range. Supposing the nets 1, 2 and 3 at site B get mapped into 49152, 49153 and 49154 by A's router. A network application on a machine on net 1 at A tries to talk to a node on net 49153; at the DDP level, the data gets passed to A's wide-area router, which remaps the net number 49153 to 2 and passes it to B's router, which correspondingly remaps the source net number from 1 to 49152 (or whatever the reserved range is that has been chosen by B's administrator), and then passes it on to its proper destination. The return message from machine on the B network goes through the corresponding transformation the other way. It's obvious I haven't thought through all the implications of this scheme. For example, what happens when you have a third site C, which also has networks numbered 1, 2 and 3? Perhaps you need a remapping on the other side of each router as well, so A can tell B's network number 1 from C's network number 1. It seems to me that resolving clashes on this remapping would be a lot easier task than having to reconfigure all the local- area routers on each site. What do other people think? Lawrence D'Oliveiro fone: +64-71-562-889 Computer Services Dept fax: +64-71-384-066 University of Waikato electric mail: ldo@waikato.ac.nz Hamilton, New Zealand 37^ 47' 29" S, 175^ 19' 16" E, GMT+12:00 It's a commentary on the state of the industry today when the revolutionary advance is seen to be, not getting an idea to work, but getting it to work under Unix.
mcgowan@zephyrus.crd.ge.com (Craig A McGowan) (07/13/90)
An number of sites on the Internet are already doing this. The mailing list we use to discuss these issues is waan@nisc.nyser.net. It works pretty well... -- Craig McGowan mcgowan@crd.ge.com
wcc@cup.portal.com (wcc - usa) (07/14/90)
Lawrence D'Oliveiro writes: > I don't know if this issue has come up before, but here goes... > > A suggestion was made to me recently (only half-serious so far) about > doing wide-area AppleTalk routing between our varsity and others > in New Zealand. > > It seems to me a solution is possible, by adding suitable > software to the wide-area AppleTalk routers, to do "network number > aliasing". Craig McGowan (mcgowan@crd.ge.com) > An number of sites on the Internet are already doing this. With AppleTalk or with other network protocols? I have a list of other perceived problems, but if it's already working somewhere I'll keep it to myself :-) Tom Evans wcc@cup.portal.com Webster Computer Corporation Suite J, 2109 O'Toole Ave. San Jose, California 95131-1303 Ph (408) 954-8054 FAX (408) 954-1832 Head Office tom@wcc.oz.au, multigate@wcc.oz.au 1270 Ferntree Gully Rd. Scoresby, Victoria, Australia Ph 61 3 764-1100 FAX 61 3 764-1179
mcgowan@zephyrus.crd.ge.com (Craig A McGowan) (07/16/90)
>With AppleTalk or with other network protocols? > >I have a list of other perceived problems, but if it's already working >somewhere I'll keep it to myself :-) > >Tom Evans The WAAN uses "IPTalk", atalkad, and administrative discipline. There is a central net number registry at waan-czar@nisc.nyser.net. For more info on this project, you should subscribe to waan@nisc.nyser.net by sending mail to waan-request@nisc.nyser.net send your questions there. -- Craig McGowan
morgan@JESSICA.STANFORD.EDU (07/17/90)
Craig McGowan writes: > The WAAN uses "IPTalk", atalkad, and administrative discipline. There > is a central net number registry at waan-czar@nisc.nyser.net. For > more info on this project, you should subscribe to waan@nisc.nyser.net > by sending mail to waan-request@nisc.nyser.net send your questions there. I'd guess that many readers of info-appletalk/comp.protocols.appletalk would be interested in what you're doing with this project, and would be interested i n a one-page summary. In particular I'd like to know how many networks and zones and organizations you support, what router hardware and software you use, and if there are any problems. I'd certainly prefer not to subscribe to yet another mailing list just to get a few questions answered, especially a list that I imagine is mostly devoted to the daily details of running your internet. If you're suggesting the waan@n isc.nyser.net mailing list as the appropriate place to discuss wide-area AppleTalk networking in general, I'd like to strongly suggest that such discussion remain here instead. - RL "Bob" Morgan Networking Systems Stanford