Re: [hylafax-users] Quirks in T.30 implementations

[Aidan Van Dyk <aidan@xxxxxxxx>]

* Steve Underwood <steveu@xxxxxxxxxxx> [100505 09:18]:
> Hi,
>
> An ECM PPS frame contains a page number, a block number and a number of  
> FCD frames. The FCD frame count has a few quirks in various  
> implementations. Does anyone know if the block number and page number  
> can be relied on to follow the T.30 spec? That is:
>
> - the page number starts at 0 at the beginning of a call, and counts up  
> until the end of the call, wrapping after 255
> - the block number starts at 0 at the beginning of each page, and counts  
> up until the end of the page, wrapping after 255

I know HylaFAX used to be loose with that, at leaset when you hit 255
pages on sending, and used to also skip page counts when skipping pages,
which was fixed.

I know of at least one big fax vendor that is very strict on it, such
that each block/page must exactly $PREV+1 (starting at 0, wrapped
255)...  Which is how we noticed both issues (skipped pages, and
wrapping at 255 pages) with HylaFAX send...  It hangs up on you if
you're page/block counters aren't strictly increasing by 1.

a.

-- 
Aidan Van Dyk                                             aidan@xxxxxxxx
Senior Software Developer                          +1 215 825-8700 x8103
iFAX Solutions, Inc.                                http://www.ifax.com/

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