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From: mrose@NRTC-GREMLIN.ARPA.UUCP
Newsgroups: mod.protocols.tcp-ip
Subject: Re: "FTAM" Implications
Message-ID: <6841.536043625@nrtc-gremlin.arpa>
Date: Sat, 27-Dec-86 02:24:21 EST
Article-I.D.: nrtc-gre.6841.536043625
Posted: Sat Dec 27 02:24:21 1986
Date-Received: Sat, 27-Dec-86 04:35:32 EST
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Approved: tcp-ip@sri-nic.arpa


    I always speak casually, but your inference was correct:  the DP
    FTAM was written at a time when the Presentation Layer was not
    solid enough to use.  It consisted of some encoding mechanisms and
    an abstract syntax methodology, but did not contain the "usual"
    network-style primitives (e.g., OPEN, CLOSE, TRANSFER).  So, the
    "sanctioned" interpretation was:

	- in FTAM you had the presentation encoding mechanisms
	- presentation was NULL
	- session did all the work

    The fact that the DIS uses presentation is not a fundamental change
    in thinking--it merely reflects the fact that the presentation
    specification can now be used.  For those of you familiar with the
    1984 CCITT recommendations on Message Handling Systems, the
    situation is identical (X.409 is used to encode/decode, X.215 is
    used to move bits).

    FTAM is File Transfer, Access, and Management.

/mtr