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- Newsgroups: comp.dcom.isdn
- Path: sparky!uunet!ukma!darwin.sura.net!udel!intercon!psinntp!wrldlnk!usenet
- From: "Michael Smith" <p00004@psilink.com>
- Subject: Q's on ASI interface for ISDN TAs
- Message-ID: <2937329326.5.p00004@psilink.com>
- Sender: usenet@worldlink.com
- Nntp-Posting-Host: 127.0.0.1
- Organization: Performance Systems Int'l
- Date: Thu, 28 Jan 1993 21:04:14 GMT
- X-Mailer: PSILink-DOS (3.3)
- Lines: 33
-
- Hope this isn't a FAQ (at any rate, it's not in the file).
-
- I've been trying to read the Application Software Interface (ASI) spec
- from the N American ISDN Users' Forum, and I find that I'm quite puzzled
- by what would seem to be elementary aspects of it. If somebody out there
- can set me straight, I'd be most grateful.
-
- 1) Does the spec provide an interface for the transfer of user data to
- the remote user and vice versa, or is it only for device control and
- call setup? There's a permissible value for "User Plane" in the
- "Protocol Identifier" field of the header, so presumably applications
- can send stuff to the user plane; I can't imagine what else would
- reasonably happen to data on the user plane except to be sent to the
- remote user and passed to it across its user plane, but on the other
- hand no message types for the user plane are defined and there isn't any
- explicit discussion of data transfer anywhere in the document, as far as
- I can tell.
-
- 2) Is it envisioned that any Level III or Level II protocols besides
- those associated with call control on the D-channel will live below the
- ASI interface (i.e. on the adapter driver side of it)? The spec says
- that the interface is envisioned as existing at the Level IV to Level
- III interface. And there are all these control blocks for various types
- of connections (clear channel, V.120, X.25 to the remote end or a PSDN,
- etc.) But are these provided only as a way of getting information to
- the Q.931 implementation so that it can use the information in call
- setup? Or are they intended to make connection parameters available to
- V.120, X.25, etc. protocol implementations below the ASI?
-
- Thanks in advance to any Good Samaritans who can lend a hand.
-
- --Michael Smith
-
-