Re: [hylafax-users] Hylafax+ With E1 card possible ?

["Andrew Rinaldi" <andrew.rinaldi@xxxxxxxxxxxx>]

Hi Steve,

Look carefully at the 'Japanese' chipsets..... you might find some surprises
about their origins.  Canon have used Rockwell (Conexant) chipsets for many
years... a lot of datapump code was broken when companies took up the
Rockwell reference designs.

I believe that one of the reasons behind the litigation issues are the
'woolly' nature of the licensing model adopted by the ITU.  It's not
uncommon for patent holders to approach 'licensed' modem vendors in the hope
of securing additional 'license' fees.

With regards to T.38 and V.34 I'm only passing on what I know.... often the
issue is not what's theoretically possible but what's actually deployed in
the field.  Let's face it, T.38 should have been done and dusted years
ago.... but everything I hear says that we are still years from a simple and
robust solution.  I'm happy to say that this is in stark contrast with the
analog fax board which at last offers 'plug-n-play' with enhanced features
such as V.34 and JBIG.... now, if we could only make it as simple to operate
as the humble fax machine then we would really have achieved something.

Regards

Andrew Rinaldi
Mainpine Developer Support
USA +1 503 822 9944 | UK +44 8458 909438
andrew.rinaldi@xxxxxxxxxxxx | www.mainpine.com

-----Original Message-----
From: hylafax-users-bounce@xxxxxxxxxxx
[mailto:hylafax-users-bounce@xxxxxxxxxxx] On Behalf Of Steve Underwood
Sent: 17 December 2007 09:46
To: hylafax-users@xxxxxxxxxxx
Subject: Re: [hylafax-users] Hylafax+ With E1 card possible ?

Andrew Rinaldi wrote:
> Hi Steve,
>
> Most of the chipsets used within the V.29/V.17 fax machines are no 
> longer available which is why I expect to see an upsurge in new V.34 
> fax machines, with more vendors moving to a V.34 only strategy.  I 
> also find it interesting that the latest Davidson report states that 
> in 2005 83.9% of fax boards sold were V.34 capable.
>   
Most FAX machines are Japanese. Most Japanese FAX machines use locally
produced chipsets, by makers most people wouldn't recognise as modem
suppliers - e.g. TDK/Teridian. They still make plenty of low end modems. 
It wouldn't surprise me to find V.34 models dominating FAX cards, but that
is almost unrelated to FAX machines. Some FAX modems seem very supplier
specific - e.g. most recent Canon FAX machines have totally broken V.29
transmit, which doesn't seem comparable to any other make of FAX machine.
They appear to either use a unique modem, or load it with special broken DSP
code.

> I understand from one of the T.38 contributors that a number of people 
> believed that V.34 was unlikely to work reliably over T.38 which is 
> why they left V.34 'for further study' in the 2002 specification.  
> I've also had a conversation with one of the IP fax server vendors who 
> said that the Cisco
> V.34 solution was not 'robust' (although to be fair they also reported 
> constant change with the Cisco V.17 firmware so maybe it's not V.34 
> specific).  One final point, V.34 is a very litigious area and this 
> might discourage T.38 vendors from implementing V.34 in the gateways.
>   
I don't know why there would be litigation issues. If you use a licenced
V.34 modem, you would appear to be in the clear. There are some bogus
patents related to T.38, including some bizarrely stupid ones progressing
through the system. E.g. a 2005 Hua Wei application for corrupting NSF
messages, that describes exactly what every T.38 gateway has done since T.38
was first published. The thing about reliability is an issue, though. The
T.38 2002 spec included messages for V.34, but seemed to leave their use a
bit vague. More recent versions have become more focussed. I'm not clear why
people expect V.34 over T.38 to be especially flaky, though many T.38
gateways disable ECM as supposedly troublesome. ECM isn't troublesome -
their networks are.

Steve


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