Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!lll-winken!ncis.llnl.gov!CS.UCL.AC.UK!S.Kille From: S.Kille@CS.UCL.AC.UK (Steve Kille) Newsgroups: comp.protocols.iso.x400.gateway Subject: Re: Some problems with RFC 987 Message-ID: <25004.602358125@UK.AC.UCL.CS> Date: 1 Feb 89 17:42:05 GMT References: <<8811290930.AA06752@jerry.inria.aristote.ATLAS.FR> Sender: daemon@ncis.llnl.gov Distribution: inet Organization: The Internet Lines: 55 Approved: post-x400-gateway@tis.llnl.gov >From: Christian Huitema >To: ifip-gtwy-request@gov.llnl.tis >Subject: Re: Some problems with RFC 987 >Date: 31 Nov 88 09:20:13+0100 >Regarding the ``Trace'' mapping, I must confess that Mailway did not follow >Steve's recommendation. Actually, we are building up the ``trace'' field >from the ``Received:'' lines -- seems much more natural. Tut tut >More precisely, the ``Received'' lines contain a host-name and a date; we >map the host name to a PRMD ID: either the PRMD to which the host belong, when >a mapping exists, or the PRMD of the gateway which serves the host, otherwise. >Then, we ``pack'' the traces by removing all duplicat occurences of a PRMD, >keeping only the earliest date as ``date of arrival''; the action is always >set to ``relayed''. The packing is sensible, and would need to be done. 987 should have said this. >We are indeed loosing some information. This is due to the limited syntax >of the Trace field in 1984-P1; it will be very naturally overcomed with >1988 P1, where we will be able to use the ``internal trace'' field, at least >for the last PRMD. I agree about internal trace - this will be a big help. >In my opinion, the solution described in the RFC-987 is not implementable: >it leads to using invalid ADMD names, and thus forbids the relaying of the >message to a public ADMD. 987 is certainly implementable! It will also be consistent with X.400. I agree that it might cause interoperability problems with those who have a restricive view of the world (PTTs in particular). >Christian Huitema I am still not sure about this one. The practicalities of this mean that: 1) You discard most of the inforamtion in the trace fields in order to squeeze into the legal format. 2) You then throw all bar one of these fields away, picking the first or last date (in practice, most items will map to either your own MD, or will not have a mapping to an MD and so still map to your own). You might as well specify discarding the information. However, I fear that you are right about the effect of the 897 mapping. It will be rejected by some ADMDs, and cause other implementations to break. Catch 22 Steve