Subject: Re: [sipcore] FW: I-D Action:draft-jones-sip-forum-fax-problem-statement-00.txt

From: "Paul E. Jones" <[email-masked]>
Date: Tue, 22 Dec 2009 23:22:57 -0500

Folks,

I didn't see any comments regarding this draft.  What is the opinion about
publishing this as an informational RFC?

Paul

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]] On
> Behalf Of Richard Shockey
> Sent: Tuesday, November 17, 2009 10:47 AM
> To: [email-masked]; [email-masked]
> Subject: [sipcore] FW: I-D Action:draft-jones-sip-forum-fax-problem-
> statement-00.txt
> 
> 
> FYI to the general SIP community.
> 
> There have been substantial field reports of difficulties with T.30 FAX
> is
> SIP networks and the SIP Forum was asked to help facilitate discussions
> among a group of technical experts in fax order to provider
> recommendations
> to either the IETF and or ITU SG16 on possible approaches to the
> problem.
> 
> Fax is a essential realtime communications service that is not going
> away
> and making fax work properly needs to be addressed.
> 
> -----Original Message-----
> From: [email-masked] [mailto:i-d-announce-
> [email-masked]]
> On Behalf Of [email-masked]
> Sent: Tuesday, November 17, 2009 3:15 AM
> To: [email-masked]
> Subject: I-D Action:draft-jones-sip-forum-fax-problem-statement-00.txt
> 
> A New Internet-Draft is available from the on-line Internet-Drafts
> directories.
> 
> 	Title           : SIP Forum - Fax Over IP Task Group Problem
> Statement
> 	Author(s)       : X. Chen, et al.
> 	Filename        : draft-jones-sip-forum-fax-problem-statement-
> 00.txt
> 	Pages           : 13
> 	Date            : 2009-11-17
> 
> This memo is published for informational purposes to document the
> issues
> identified by the SIP Forum with respect to the transmission of
> facsimile
> signaling messages and fax page data over Internet Protocol (IP)
> networks.
> Further, it is the intent of this memo to alert the IETF to the
> formation of
> a Fax Over IP Task Group within the SIP Forum chartered to investigate
> and
> address identified issues as they relate to the deployment of fax
> services
> in Session Initiation Protocol (SIP) networks.
> 
> A URL for this Internet-Draft is:
> http://www.ietf.org/internet-drafts/draft-jones-sip-forum-fax-problem-
> statem
> ent-00.txt
> 
> Internet-Drafts are also available by anonymous FTP at:
> ftp://ftp.ietf.org/internet-drafts/
> 
> Below is the data which will enable a MIME compliant mail reader
> implementation to automatically retrieve the ASCII version of the
> Internet-Draft.
> 
> _______________________________________________
> sipcore mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/sipcore
>

---

From: Dean Willis <[email-masked]>
Date: Wed, 23 Dec 2009 21:24:25 -0600

> publishing this as an informational RFC?

I'm sympathetic to the fax problem.

But I'm not sure what the intent of publishing this draft as an RFC 
might be. It reads more like a liaison statement from FaxTG to IETF 
informing IETF of what FaxTG is working on. We have a less costly 
pulication route for LS available that might be a better alternative if 
that's the case.

If, however, you're leading towards another fax effort in IETF, then it 
might make sense to take this draft along the individual informational 
route.

--
Dean

---

From: "Paul E. Jones" <[email-masked]>
Date: Wed, 23 Dec 2009 22:56:57 -0500

Dean,

The intent is not only to inform the IETF, but the public at large as to the
issues identified with fax transmission.

The next step is to try to fix the problems.  That might result in the
creation of one or more documents that prescribes a solution.  Will that be
in the ITU or IETF, or both?  I don't know.  (I'm just serving as editor.)

Let's assume the work is only done in the ITU.  Would the IETF want to
publish an Informational document at all?  It sounds like that answer might
be "no".

If the SIP Forum plans to come back to the IETF with some work, how ought we
change this document to "pave the way" for that kind of work?  I know a few
folks working in the SIP Forum are on this list, but I'll take any feedback
you and others provide to the group to ensure the message is conveyed.

Paul

PS - Merry Christmas, everyone!

> Behalf Of Dean Willis
> Sent: Wednesday, December 23, 2009 10:24 PM
> To: Paul E. Jones
> Cc: [email-masked]
> Subject: Re: [sipcore] FW: I-D Action:draft-jones-sip-forum-fax-
> problem-statement-00.txt
> 
> Paul E. Jones wrote:
> > Folks,
> >

---

From: "Richard Shockey" <[email-masked]>
Date: Thu, 24 Dec 2009 11:36:11 -0500

The intent of the draft is to inform and clearly document to the IETF SIP
community that "there is a problem" with fax in SIP networks. In fact, the
problem seems to be much worse than some of us have originally believed. 

I recently met with several folks from the international wholesale carrier
community (the i3forum ) who are reporting similar problems with fax in
their networks. These issues have the potential for delaying significant SIP
deployment in these networks, aka loss of sales for the supplier community.
(hint)

Let us not forget that fax is a essential communications service in the PSTN
and that SIP networks MUST figure out ways to accommodate it.

The SIP Forum Fax Task group is currently investigating the problems
documented in the draft and taking additional input from all parties.
Everyone in the IETF SIP Community is free to participate in this work.

http://www.sipforum.org/content/view/310/252/

The goal is to develop a formal SIP Forum recommendation on what steps can
be taken to fix the problems. If it is determined that either SIP or T.38
protocols needs to be modified in some way then a follow on document ( ID or
ITU Liaison letter ) will be developed suggesting alternatives for
consideration.

With that follow up document in mind I do think is important to publish the
fax problem statement as Informational.

Richard Shockey
Shockey Consulting
Chairman of the Board of Directors SIP Forum
PSTN Mobile: +1 703.593.2683
<mailto:richard(at)shockey.us>
skype: rshockey101 
LinkedIn : http://www.linkedin.com/in/rshockey101
http//www.sipforum.org

>  From: Dean Willis [mailto:[email-masked]]
>  Cc: 'Richard Shockey'; [email-masked]

---

From: Paul Kyzivat <[email-masked]>
Date: Thu, 24 Dec 2009 15:33:32 -0500

I know this is a bit off topic, and doesn't alleviate the problem, but 
has anybody ever proposed that an INVITE with offer for fax be responded 
  to with a 3xx containing a mailto: URI? Or that ENUM for a fax device 
yield a mailto uri?

	Thanks,
	Paul

Richard Shockey wrote:
> dispatch mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/dispatch
>

---

From: "Paul E. Jones" <[email-masked]>
Date: Thu, 24 Dec 2009 16:26:57 -0500

Paul,

That could certainly be done and T.37 could be used on gateways to make that
work.

But, as you said, it does not fix the problem with T.38.  Perhaps equally
important, I think there are many, many businesses that will not be moving
to email anytime soon.  I wish they would -- that would solve this problem
:-)
 
Paul

> Behalf Of Paul Kyzivat
> Sent: Thursday, December 24, 2009 3:34 PM
> To: Richard Shockey
> Cc: 'Paul E. Jones'; [email-masked]; [email-masked]
> Subject: Re: [sipcore] [dispatch] FW: I-D Action:draft-jones-sip-forum-
> fax-problem-statement-00.txt
> 
> >>  > I didn't see any comments regarding this draft.  What is the
> opinion
> >>  about
> >>  pulication route for LS available that might be a better
> alternative
> >>  if
> >>  that's the case.
> >>
> >>  If, however, you're leading towards another fax effort in IETF,
> then
> >>  it

---

From: "Richard Shockey" <[email-masked]>
Date: Sat, 26 Dec 2009 12:22:47 -0500

Paul its certainly not off topic and a reasonable idea, but not practical
for a number of reasons. What you describe is a classic T.37 mode for fax
that the old IETF Fax WG documented in RFC 3965. The problem is "non
repudiation". Fax has a certain legal standing and there is the requirement
that there be actual documentation that a fax was sent by foo at such and
such a time to bar and that the service provider or appropriate intermediary
can provide the appropriate documentation of such a transaction.

The problem is becoming more acute due to a variety of regulations, HIPPA
and USA SOX, real estate etal which require the transmission of a signature
as part of a legal filing and no, digital signatures have not proven to be
successful even though they have legal standing in most countries now.
Health care records cannot be sent by email for privacy reasons especially
test results.

Fax is pretty simple and it works for these class of transactions. As a
result my contacts in the fax industry have noted a minor resurgence in fax
machine and fax port sales. 

Some of us years ago thought using a variant of the Internet Print Protocol,
based on HTTP for real time document transmission would have been a better
idea but that went nowhere as well.

The issue is there something in SIP signaling that can alert the first hop
what this session really is such as ;USER=FAX that can help. I don't know,
that is what needs to be investigated.

>  From: Paul Kyzivat [mailto:[email-masked]]
>  Cc: 'Dean Willis'; 'Paul E. Jones'; [email-masked];
>  [email-masked]
>  Subject: Re: [dispatch] [sipcore] FW: I-D Action:draft-jones-sip-
>  forum-fax-problem-statement-00.txt
>

---

From: "Paul E. Jones" <[email-masked]>
Date: Sat, 26 Dec 2009 15:47:16 -0500

Richard,

All of your points are correct, though I think the biggest reason why fax is
important is that fax is simple and works.  (Well, except that it does not
work well on SIP networks, thus the reason we're discussing this.)

The statement about legal standing of faxes is something I've often heard,
but I've been curious about it.  How could a fax document have any legal
standing when I can so easily (and legally) forge the phone number I use to
place the call?  If "legal reasons" are the primary reason for using fax, I
believe we could find a more modern solution to the need to transmit paper
documents.

I think it's important to solve the fax issues, because that's the
technology people have in their hands right now.  That said, I'll also tell
you that I really, really like those new "scan / PDF / email" machines we
have in our office.  I can't say enough good words about those machines and
I now use those (or just a simple scanner) when I need to sign and transmit
legal documents.  I've not used a fax machine in years.  While there is a
non-repudiation issue, that bothers me very little since I know someone
could easily take my signature and insert it into a document and fax it.  At
the end of the day, issues can only be resolved by having a person swear
under oath that he/she did or did not produce/sign/transmit some document.

I think our society sometimes goes overboard with their perception of
"security".  People do not fully understand that most security measures are
not "secure" but just assurance levels.  As evidence to this misguided
thought, I went to the bank one day this year to withdraw money.  The teller
did not like my signature because it did not match the one she had on file
from 10 years ago. "Forget about the signature: it's not that important", I
told her.  She could not believe I would utter such a thing.  As far as she
was concerned, that signature meant everything in the world in terms of
security.  For me, though, my identification and me standing right before
you has more weight.  The lady who works by the front door of the bank has
been there since I started banking there and she knows me by name, so I told
the teller to ask her to come over and verify my identity.  She refused.
She put more trust in that signature than she would in my face, my
identification card, and the word of an employee who knew me as decade-long
customer.  But, I bet she was just following some misguided directions in
the name of "security".

The point is that the tools we put into place only help to provide some
level of assurances, and fax is relatively weak in that regard.  It's even
worse than my signature, since so many aspects of that document can be
forged.  (Heck, a pair of alligator clips are the only tools one needs to
intercept PSTN calls, and it takes little more than that to alter the
transmitted fax data.)

So, I that we really have two issues:
1) We need to resolve the fax transmission issues in SIP networks, because
fax is being used by many, many businesses and might even be the primary
business tool for some businesses.  How long will this be the norm?
2) We need to explore alternatives that can provide whatever reasonable
assurances we can.  It seems the market is setting the direction here
(emailed PDF documents), as I am seeing this capability in relatively
low-end machines at Office Depot now.  Perhaps this is sufficient, as we now
have tools like DKIM, S/MIME, etc. to assist with the assurance aspects.

What Paul K. was suggesting, I guess, was to start migrating from (1) to (2)
through the use of NAPTR records.  I think it's a reasonable thing to
consider, as I believe the world is moving to (2), anyway.  I just doubt the
world will move entirely to email or any other transmission system for a few
years, so I don't want us to be distracted from the immediate problem at
hand, else we'll be fighting this another 10 years.

Paul

> From: Richard Shockey [mailto:[email-masked]]
> Sent: Saturday, December 26, 2009 12:23 PM
> To: 'Paul Kyzivat'
> Cc: 'Dean Willis'; 'Paul E. Jones'; [email-masked]; [email-masked]
> Subject: RE: [dispatch] [sipcore] FW: I-D Action:draft-jones-sip-forum-
> >  > community (the i3forum ) who are reporting similar problems with
> fax
> >  in
> >  > Let us not forget that fax is a essential communications service
> in
> >  the PSTN
> >  > be taken to fix the problems. If it is determined that either SIP
> or
> >  T.38
> >  > protocols needs to be modified in some way then a follow on
> document
> >  ( ID or

---

From: "Richard Shockey" <[email-masked]>
Date: Sun, 27 Dec 2009 15:57:43 -0500

>  Richard,
>  
>  All of your points are correct, though I think the biggest reason why
>  fax is  important is that fax is simple and works.  (Well, except that it
does
>  not  work well on SIP networks, thus the reason we're discussing this.)

Exactly .. its an essential PSTN communications service that SIP networks
must be able to support. Its clean simple and its works ..just like phone
numbers.

>  The statement about legal standing of faxes is something I've often
>  heard,  but I've been curious about it.  How could a fax document have
any
>  legal  standing when I can so easily (and legally) forge the phone number
I
>  use to  place the call?  If "legal reasons" are the primary reason for
using
>  fax, I  believe we could find a more modern solution to the need to
transmit
>  paper documents.

I know .. but it's the 3rd party validation of the transaction through
carrier networks that carries some of the legal weight. Though with some
checking I found out that in the US because of the Uniform Electronic Clear
Transactions Act of 1999, and various legislature passed since then,
contracts are no longer limited to pristine original copies on clean, white
paper. Fax is preferred to email for health care transactions due the
perceived notion that fax is more "secure" a point to point communication
without intermediaries.

In fact, according to the UETA, email and fax contracts are now legally
binding. This means that any agreement you make through any medium -
electronic or otherwise - will hold up in court. As for alternative real
time transport I had this argument 15 years ago in the FAX WG and as I
mentioned HTTP would be much more useful transport for documents but alas
for reasons I don't need to go into that did not happen.

>  technology people have in their hands right now.  That said, I'll also
>  tell  you that I really, really like those new "scan / PDF / email"
machines
>  we  have in our office.  I can't say enough good words about those
>  machines and  I now use those (or just a simple scanner) when I need to
sign and
>  transmit legal documents.  

Yep I worked on one of the originals as a consultant years ago ..HP's
Digital Sender. Great device still have one in my office gathering dust.

>  "security".  People do not fully understand that most security
>  measures are  not "secure" but just assurance levels.  As evidence to
this misguided
>  thought, I went to the bank one day this year to withdraw money.  The
>  teller  did not like my signature because it did not match the one she
had on
>  file  from 10 years ago. "Forget about the signature: it's not that
>  important", I>  told her.  She could not believe I would utter such a
thing.  As far
>  as she  was concerned, that signature meant everything in the world in
terms
>  of  security.  

Yep that the key ..

>  1) We need to resolve the fax transmission issues in SIP networks,
>  because  fax is being used by many, many businesses and might even be the
>  primary  business tool for some businesses.  How long will this be the
norm?

Probably till we're dead. 

>  2) We need to explore alternatives that can provide whatever
>  reasonable>  assurances we can.  It seems the market is setting the
direction here
>  low-end machines at Office Depot now.  Perhaps this is sufficient, as
>  we now  have tools like DKIM, S/MIME, etc. to assist with the assurance
>  aspects.

We're geeks ..we think that is the direction the market is going. The
reality of carrier networks is very different and don't get me started on
DKIM AND S/MIME as solutions. 

>  
>  What Paul K. was suggesting, I guess, was to start migrating from (1)
>  to (2)  through the use of NAPTR records. 

You want a lecture on why RFC 3761 [ENUM] in e164.arpa failed? I regularly
give lectures on that subject. To Paul's point it would be trivial but even
private carrier enum systems have their deployment issues.

 I think it's a reasonable thing to
>  consider, as I believe the world is moving to (2), anyway.  I just
>  doubt the  world will move entirely to email or any other transmission
system for
>  a few years, so I don't want us to be distracted from the immediate
problem
>  at hand, else we'll be fighting this another 10 years.

To your point the problem at hand is that SIP carrier networks still need to
handle T.30 fax and ultimately they are paying a lot of our salaries. I
thing the FAX task group in the SIP Forum has made a excellent start but
they still need input.

>  > for a number of reasons. What you describe is a classic T.37 mode
>  for
>  > fax
>  > that there be actual documentation that a fax was sent by foo at
>  such
>  > and
>  > as part of a legal filing and no, digital signatures have not proven
>  to
>  > be
>  > result my contacts in the fax industry have noted a minor resurgence
>  in
>  > fax
>  > The issue is there something in SIP signaling that can alert the
>  first
>  > hop
>  > >  I know this is a bit off topic, and doesn't alleviate the
>  problem,
>  > but

---

From: Paul Kyzivat <[email-masked]>
Date: Mon, 28 Dec 2009 13:31:41 -0500

I'm not going to pretend that I know the issues here.
Some of them seem to be irrational, but that doesn't make them any less 
real. (Surely nobody considers government and law making rational.)

What I had in mind was using email to transmit the same bits that would 
otherwise be transmitted via T.38. That does involve *different* 
intermediaries, but probably not *more* of them than transmitting via 
sip. It would be another optimization above that to transmit the doc in 
a more symbolic encoding.

I suppose the real issue is *which* intermediaries, and who is in a 
position to vouch for their security. It they are all controlled by same 
service providers it wouldn't really matter, would it?

Suppose we were considering the case of traditional fax machines on both 
ends, connected via traditional telephony infrastructure to gateways 
that then communicate via sip. In such a case, would it really matter if 
the gateways decided to transmit fax using email rather than sip?

	Thanks,
	Paul

---

From: Dean Willis <[email-masked]>
Date: Tue, 29 Dec 2009 01:22:20 -0600

>  to with a 3xx containing a mailto: URI? Or that ENUM for a fax device 

I was going to say "redirect to T.37, since real-time fax over VoIP is 
just a bad idea" but Paul beat me to it.

Seriously: fax over IP really only works when the real-time conversion 
is done close to the edge of the IP network. and the core transit is 
store-and-forward/ The close to the consumer edge, the better. Trying to 
retrofit the timing equirements of fax onto RTP is an exercise in 
futility for those who don't understand the concept of lossy networks.

--
Dean