Xref: utzoo comp.sys.ibm.pc:23154 alt.fax:21 comp.protocols.iso:194
Path: utzoo!attcan!uunet!lll-winken!ames!ncar!mailrus!sharkey!emv
From: emv@a.cc.umich.edu (Ed Vielmetti)
Newsgroups: comp.sys.ibm.pc,alt.fax,comp.protocols.iso
Subject: Group 4 fax (i.e., greyscale fax)
Message-ID: <6255@mailgw.cc.umich.edu>
Date: 12 Jan 89 18:43:10 GMT
References: <6084@mailgw.cc.umich.edu> <2384@spdcc.SPDCC.COM> <2388@spdcc.SPDCC.COM> <966@riddle.UUCP>
Reply-To: emv@mailgw.cc.umich.edu (Ed Vielmetti)
Followup-To: alt.fax
Organization: University of Michigan Computing Center, Ann Arbor
Lines: 14

In article <966@riddle.UUCP> domo@riddle.UUCP (Dominic Dunlop) writes:
>[My understanding is that group 4 goes at 64 kbit/sec, and requires a
>digital circuit (such as an ISDN connection).  Right or wrong, anybody?
>(Group 3 goes at 9600 bits/sec over a voice connection.)]

I have the Group 4 Fax recommendation (T.5) in front of me.  It states:

"1.1	Group 4 facsimile apparatus is used mainly on public data networks
(PDN) including circuit-switched, packet-switched, and the integrated
services digital network (ISDN).  The apparatus may be also used on the
public switched telephone network (PSTN) where an appropriate modulation
process will be utilized."

--Ed