Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!att!cbnewsj!cbnewsi!hrs1
From: hrs1@cbnewsi.att.com (herman.r.silbiger)
Newsgroups: comp.dcom.fax
Subject: Re: welcome to faxtasy island:  the CCITT spec for Group 3
Summary: obsolete version of T.4
Message-ID: <1990Dec15.200923.3262@cbnewsi.att.com>
Date: 15 Dec 90 20:09:23 GMT
References: <137629@pyramid.pyramid.com> <19720@know.pws.bull.com>
Organization: AT&T Bell Laboratories
Lines: 39

In article <19720@know.pws.bull.com>, eli@pws.bull.com (Steve Elias) writes:
> in response to John Palasz who wanted pointers to books and 
> technical info on fax...  the "red book" for fax (or is it a 
> blue book now?) is available from omnicom at 1-800-omnicom.
> i think the relevant book is called VIII.7 -- though i'm not sure.
> 
> below is the CCITT spec for Group 3 encoding and transmission.
> it says "draft recommendation", but i think it's pretty accurate.
> it's about 16k. 
> 
> 
> RFC 804
> 
>  
>                CCITT Draft Recommendation T.4
>  
>  
>   As Defined In: CCITT STUDY GROUP XIV, CONTRIBUTION No.25-E
>  
> SOURCE: DRAFTING GROUP ON DRAFT RECOMMENDATION T.4
> TITLE: DRAFT RECOMMENDATION T.4 - STANDARDIZATION OF GROUP 3
>     FACSIMILE   APPARATUS   FOR  DOCUMENT  TRANSMISSION  (as
>     amended and agreed by Working Party XIV/2)
>

The copy of Rec. T.4 posetd here dates from about 1979, and is not identical to the one approved in 1980,  and which has been amended since.

The fax standardization was moved from SG XIV to SG VIII in 1980.

T.4 is less than half of the recommendations covering G3.  The protocol is
defined in Rec. T.30, which is presently undergoing revision (see prevous 
posting followup.

Its is never a good idea to use anything but the latest approved version of a 
standard, changes are sometimes made in the last meeting!

Herman Silbiger
hsilbiger@attmail.com