Path: utzoo!attcan!uunet!cs.utexas.edu!rutgers!psuvax1!psuvm!psuecl!lear!hta From: harald.alvestrand@elab-runit.sintef.no Newsgroups: comp.protocols.iso.x400 Subject: Re: ISO conferencing? Keywords: conformance Message-ID: <1990Jul18.105114.7009@idt.unit.no> Date: 18 Jul 90 10:51:14 GMT References: Sender: news@idt.unit.no (Usenet news admin) Reply-To: harald.alvestrand@elab-runit.sintef.no Organization: ELAB-RUNIT, SINTEF, Norway Lines: 30 Approved: usenet@ICS.UCI.EDU Autoforwarded: true MMDF-Warning: Parse error in original version of preceding line at ICS.UCI.EDU In , Bob writes: > X.400/15.4 "MHS Security Capabilities" include several that seem > problematic for news - particularly proof of delivery, flow > confidentiality, and message sequence integrity, which raise > architectural issues with news' flood transport algorithm. The other > authentication, content confidentiality, and content integrity matters > are at least workable. MT (Message Transfer service) non-delivery > indication seems like something to avoid in a news-like environment, > given the rampant fluidity of news transport connectivity. As a general hint: I think that people reading X.400/88 think "Do I have to implement all this?" The answer is NO. What should be implemented (IMHO) is the ability to reject messages if they have used an extension that the currently receiving mailbox does not support. So, X.400/88 implementations should really only support what is required for the applicatons that they will support. An X.400 based route into the "OSI news service" would have little reason to support proof-of-delivery, if the model is such that "delivery" in X.40 terms occurs at the reader's site, and not at the X.400-to-"OSI news" interface. So any message asking for proof-of-delivery and saying that this is critical for relay or delivery, should be rudely rejected. So should ANY message asking for delivery notification, for that instance. (except for "checkgroups equivalents????") 10.000 delivery notifications will increase network load appreciably. Good luck to you! Harald Tveit Alvestrand