tinkelman@CCAVAX.CAMB.COM (Bob Tinkelman) (02/03/90)
A month or so ago, I posted a query regarding MRchan, a PMDF Message-Router-channel that we had written here at CCA, and were in the process of enhancing. I asked for input as to what features were desirable/necessary. I received an encouraging number of replies, some of which lead to extended mail discussions of some of the issues and tradeoffs involved. In my original posting I promised to compose a summary of the responses. There certainly appears to be sufficient interest to post it to the list. So here it is. First, a couple of the respondents were interested only in a full RFC987 compliant X.400-to-RFC822 gateway. [Presumably, they're now interested in an RFC1138 compliant gateway.] We are *not* doing this. To review, what we are trying to do is to write a PMDF-channel/MR-user-agent which, together with PMDF, implements an RFC822-to-MailBus gateway with the following basic properties: 1. Universality. For any given legal 822-To-address, there should be a way for that address to be specified on the MR-side of the gateway. Similarly for the other direction. [This does *not* say that your particular mailer will let you type it! It says only that it is a legal 822 address (on the 822 side) or a legal Message Router route (on the MR side).] 2. REPLYability. Mail passing in either direction across the gateway should be REPLYable. With no special effort on the part of the mail sender, the gateway should transform any legal From-address on one side into a legal From-address on the other via an invertible mapping, so that a recipient of the mail can use the From-address as a To-address in replying to the originator. [Like point 1 above, there is the proviso that you your mailer must let you enter the address. For example, if you have an 8 character limit on what you can type, ...] 3. Domain names. Postmasters should be able to configure the gateway so that mail on the Internet side addressed to name@host will get delivered to a specified MailBus accessible system. In addition, mail coming from that MailBus system should be delivered on the Internet side with a From-address in the domain form, name@host. [Our scheme requires the postmaster to specify, in PMDF.CNF, the correspondence between domain name and MR-route on a per-host basis. These specifications are *not* required for Universality or REPLYability.] I had asked about the interest in using MRchan as a `bridge' between MRs on different DECnets. Only one or two respondents had an interest in this. Two people brought up the issue of encoding binary files (like WK1 format Lotus 123 spreadsheets) before transferring them from the MR side to the PMDF side. We hadn't given this any thought. Presumably it would be of use only in configurations where we were bridging isolated MailBus networks. Or (please tell me) is there any standard out there for using UUENCODE (or something else) and marking the mail header so that a recipient mail system can recognize that the mail has to be UUDECODEd? One person suggested a mail header of the form ``X-Encoded: Uuencode''. I asked about the inverse configuration - using a MailBus network as a transport between two PMDF sites. This would be a little strange. Nobody expressed any interest. I asked about the issue of handling the general tree-structure of MR messages. Nobody seemed to want anything more than a conversion of these to flat text files with human readable separators (like a line of dashes and the text ``Attachment''). Nobody seemed to require that an originator on the Internet side be able to compose a mail message which would be delivered, on the MR side, with multiple message parts. I had asked about integration with DEC's Distributed Directory Service. Nobody seemed interested in this. Nobody who responded used DEC's MailBus Monitor software. Most everyone who responded used Message Router only for ALL-IN-1. I would like to thank everyone who responded to my original posting. We are not yet ready to send out software to beta-test sites. (Real work continues to interfere with progress.) I'll send further mail where we are. If anyone else is interested in being a beta-test site, please send me mail describing your configuration. Also, any other/further feedback would be helpful and most welcome. -- Bob Tinkelman, Cambridge Computer Associates, Inc., 212-425-5830 bob@ccavax.camb.com or ...!uunet!ccavax!bob