[Ecrit] Re: Ecrit Digest, Vol 13, Issue 20
"Hansen, Jenny <Contractor>" <Jenny.Hansen@nhtsa.dot.gov> Thu, 16 February 2006 02:23 UTC
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From: "Hansen, Jenny <Contractor>" <Jenny.Hansen@nhtsa.dot.gov>
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Subject: [Ecrit] Re: Ecrit Digest, Vol 13, Issue 20
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I agree w/Henning. From an operational standpoint, old salt dispatcher that I am, have the call (all of them) routed to the Primary PSAP. Jenny Hansen NG9-1-1 -------------------------- Sent from my BlackBerry Wireless Handheld -----Original Message----- From: ecrit-bounces@ietf.org <ecrit-bounces@ietf.org> To: ecrit@ietf.org <ecrit@ietf.org> Sent: Wed Feb 15 21:20:21 2006 Subject: Ecrit Digest, Vol 13, Issue 20 Send Ecrit mailing list submissions to ecrit@ietf.org To subscribe or unsubscribe via the World Wide Web, visit https://www1.ietf.org/mailman/listinfo/ecrit or, via email, send a message with subject or body 'help' to ecrit-request@ietf.org You can reach the person managing the list at ecrit-owner@ietf.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Ecrit digest..." Today's Topics: 1. Re: ECRIT support for TTY/TDD calls (Henning Schulzrinne) 2. RE: ECRIT support for TTY/TDD calls (Brian Rosen) 3. Re: ECRIT support for TTY/TDD calls (Rockford9@aol.com) ---------------------------------------------------------------------- Message: 1 Date: Wed, 15 Feb 2006 20:05:46 -0500 From: Henning Schulzrinne <hgs@cs.columbia.edu> Subject: Re: [Ecrit] ECRIT support for TTY/TDD calls To: "Gunnar Hellstrom" <gunnar.hellstrom@omnitor.se> Cc: 'Gregg Vanderheiden' <gv@trace.wisc.edu>, "'Aquil, Kamran'" <kamran.aquil@mitretek.org>, ecrit@ietf.org Message-ID: <232E09D4-6327-4A28-9A1D-D469E4CEA48D@cs.columbia.edu> Content-Type: text/plain; charset=WINDOWS-1252; delsp=yes; format=flowed I don't think we want a service label for each media type. While *today* there are PSAPs that only answer TTY calls, is this likely to make sense in an all-IP PSAP environment where the media would terminate on the same PC that's used for IM, video and so on? Why would you do this? Rather than trying to put SDP in a URN, maybe the better solution is to route to one PSAP for the emergency service and have that PSAP then redirect the call based on the full SDP information, if this becomes necessary. That way, you can deal with situations where the caller can handle a variety of means of communications, albeit with different ease, and the PSAP has access to the full media information. Since this could be added on later if necessary, once we know whether anybody actually needs this, maybe it's better to avoid gratuitous complexity, both in terms of protocol operation, testing (yet another thing a mapping protocol has to test) and user agents. Henning On Feb 15, 2006, at 6:52 PM, Gunnar Hellstrom wrote: > What would sos.police.tty do and how would it be invoked? > > If it could lead to a text capable IP terminal, it should be called > sos.police.real-time-text or so. > > If it helps to find a PSTN based PSAP with text capabilities, it > could be called sos.police.txp > > tty is a US term. > > Gunnar > > ---------------------------------------------------------------------- > ------- > Gunnar Hellström, Omnitor > gunnar.hellstrom@omnitor.se > Mob: +46 708 204 288 > Phone: +46 8 556 002 03 > www.omnitor.se > -----Original Message----- > From: Brian Rosen [mailto:br@brianrosen.net] > Sent: Thursday, February 16, 2006 12:17 AM > To: 'Gunnar Hellstrom'; ecrit@ietf.org; 'Aquil, Kamran'; 'François > D. Ménard' > Cc: 'Gregg Vanderheiden' > Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls > > All I get out of this for ecrit is that we need entries for > sos.police.tty in the service registry > > > > Brian > > > > From: Gunnar Hellstrom [mailto:gunnar.hellstrom@omnitor.se] > Sent: Wednesday, February 15, 2006 5:47 PM > To: ecrit@ietf.org; 'Aquil, Kamran'; br@brianrosen.net; François D. > Ménard > Cc: Gregg Vanderheiden > Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls > > > > It is quite widely accepted now that real-time text transmitted > with its own text coded RTP payload RFC 4103 is used to carry text > that may be gatewayed to/from TTY/TDD/textphones in PSTN. > > > > It is discussed in http://www.ietf.org/internet-drafts/draft-ietf- > sipping-toip-03.txt > > > > And it is documented in http://www.ietf.org/internet-drafts/draft- > sinnreich-sipdev-req-08.txt > > > > Also other standardisation bodies have picked up the real-time text > concept in IP networks, and pointed at RFC 4103 (or its compatible > predecessor RFC2793 ). E.g. 3GPP and ETSI. > > A couple of years ago we had an intensive discussion in the SIMPLE > mail list about the possibility to use MSRP to carry the real-time > text medium, but we concluded that it would cause too much overhead > or too much delay for the users, so that RTP was recommended > instead. The most common use of MSRP is to not transmit until end > of sentence, while for real time text, transmission is required > with at most 500 ms interval as long as there is anything to > transmit in order to maintain the real-time feeling of being in > touch in a conversation through this medium. > > > > Quite commonly you will connect a text RTP stream and an audio RTP > stream and possibly a video RTP stream in the same call, so that > you will get an enhanced multimedia phone call with all supported > media > > > > The ecrit requirements also mentions this correspondence > > in www.ietf.org/internet-drafts/draft-ietf-ecrit-requirements-03.txt > > > Re4. Multiple Modes: Multiple communication modes, such as audio, > video and text messaging MUST be supported. > > Motivation: In PSTN, voice and text telephony (often called > TTY or > textphone in North America) are the only commonly supported > media. > Emergency calling must support a variety of media. Such media > should include voice, conversational text (RFC 4103 [9]), > instant > messaging and video. > > > > I am working in a European group where one of the goals is to agree > on handling text users' requirements on emergency calling in IP > networks. Of course we want to agree on global solutions if possible. > > > > Address mapping is one important and tricky question for text > users. It is true that different countries have different > approaches on emergency calling with PSTN Text telephones (TTYs). > Some have the same number as voice users, while others have > specific numbers. On the SIP side it would be good to have the same > URL and make any required routing based on declared media, mode and > language capabilities and preferences. > > > > Text capable gateways are not at all as common as VoIP gateways, so > if the PSAP is still in PSTN, there is a need to have a good > mechanism for routing emergency calls from SIP into PSTN through a > text capable gateway. I cannot say that the mechanisms for finding > the right gateway and make the proper address mapping to a PSTN > number is solved yet for the text calls, and it would be excellent > if we could have that topic in mind in the discussions and get > proper methods documented. > > > > I have drafted, but not yet submitted a registration of a SIP URL > and an ENUM subservice for real-time text. It might be helpful for > finding text gateways and mapping addresses and (text) numbers, but > I would like to see some scenarios thoroughly discussed before > adding SIP URL and another ENUM subservice. > > > > Would there be any benefit of being allowed to enter TXP:112 or > having ENUM to find an appropriate address if I call 112 from a > SIP multimedia phone declaring text capabilities with m=text in sdp? > > > > > > Gunnar > > ---------------------------------------------------------------------- > ------- > > Gunnar Hellström, Omnitor > > gunnar.hellstrom@omnitor.se > > -----Original Message----- > From: ecrit-bounces@ietf.org [mailto:ecrit-bounces@ietf.org]On > Behalf Of François D. Ménard > Sent: Wednesday, February 15, 2006 5:14 PM > To: br@brianrosen.net; 'Aquil, Kamran'; ecrit@ietf.org > Subject: Re: [Ecrit] ECRIT support for TTY/TDD calls > > > I made a contribution to CISC NTWG on use of SIP for transporting > TDD traffic: > > http://www.crtc.gc.ca/cisc/COMMITTE/N-docs/NTCO0338.doc > > I think it may be relevant to ECRIT. > > -=Francois=- > > > On 2/15/06 10:51 AM, "Brian Rosen" <br@brianrosen.net> wrote: > > Within the scope of our work, I don't see how TDD services are > impacted until we get to the architecture effort, which probably > has to have some sections on that subject. > With respect to the mapping protocol, I do not believe there is any > impact at all. > With respect to the sos service urn, I do not believe there is any > impact at all > > Ecrit doesn't have scope to talk about any kind of gateways or > codec support. > > Ah! My BCP on phones and proxies may need some mention, although > this is the IETF, and I don't think the ploy of forcing the entire > PSTN to support TDD just so 9-1-1 TDD will work. That effort would > have to be in the general SIP arena. > > Brian > > > From: ecrit-bounces@ietf.org [mailto:ecrit-bounces@ietf.org] On > Behalf Of Aquil, Kamran > Sent: Wednesday, February 15, 2006 10:31 AM > To: ecrit@ietf.org > Subject: [Ecrit] ECRIT support for TTY/TDD calls > > > Folks, > > > > Like to know if there are specific ECRIT requirements recognizing > support for Telecommunications Device for the Deaf (TDD) services > for the hearing impaired. If not is this left for VOIP/SIP gateways > to perform this requirement of translating the TDD calls to Text > and Speech encoding. Wanted to make sure how ECRIT meet requirement > for TDD services. > > > > Regards, > Kamran Aquil > Intelligent Transportation Systems- Division > Mitretek Systems. > > > > > > _______________________________________________ > Ecrit mailing list > Ecrit@ietf.org > https://www1.ietf.org/mailman/listinfo/ecrit > > > > -- > Francois D. Menard > fmenard@xittelecom.com > > > _______________________________________________ > Ecrit mailing list > Ecrit@ietf.org > https://www1.ietf.org/mailman/listinfo/ecrit ------------------------------ Message: 2 Date: Wed, 15 Feb 2006 21:17:15 -0500 From: "Brian Rosen" <br@brianrosen.net> Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls To: "'Henning Schulzrinne'" <hgs@cs.columbia.edu>, "'Gunnar Hellstrom'" <gunnar.hellstrom@omnitor.se> Cc: "'Aquil, Kamran'" <kamran.aquil@mitretek.org>, ecrit@ietf.org, 'Gregg Vanderheiden' <gv@trace.wisc.edu> Message-ID: <070c01c6329f$1d36b030$640fa8c0@cis.neustar.com> Content-Type: text/plain; charset="iso-8859-1" If a country has a dialstring that is the text-to-police dialstring, then we must map it into a unique urn unless we know that in every instance we can differentiate the text calls from voice calls. I suspect that's hard. With a SIP URI, you know you can use media negotiation to get the text codec, and if the PSAP accepts the text call, then the mapper will have the same result for sos.police.txt as sos.police. If you have to map instead to some older technology, you have to differentiate (that is, the mapping will be different). It may be that we make an assumption that the mapping function does not yield a URI if the PSAP doesn't accept a call with a negotiated text codec, which would mean we don't need to have sos.police.txt. That would force backwards compatibility to existing systems when mapping fails. That's not terrible, but I thought it made more sense to let mapping yield a URI that resolved to the older technology. Brian -----Original Message----- From: Henning Schulzrinne [mailto:hgs@cs.columbia.edu] Sent: Wednesday, February 15, 2006 8:06 PM To: Gunnar Hellstrom Cc: br@brianrosen.net; ecrit@ietf.org; 'Aquil, Kamran'; 'François D. Ménard' ; 'Gregg Vanderheiden' Subject: Re: [Ecrit] ECRIT support for TTY/TDD calls I don't think we want a service label for each media type. While *today* there are PSAPs that only answer TTY calls, is this likely to make sense in an all-IP PSAP environment where the media would terminate on the same PC that's used for IM, video and so on? Why would you do this? Rather than trying to put SDP in a URN, maybe the better solution is to route to one PSAP for the emergency service and have that PSAP then redirect the call based on the full SDP information, if this becomes necessary. That way, you can deal with situations where the caller can handle a variety of means of communications, albeit with different ease, and the PSAP has access to the full media information. Since this could be added on later if necessary, once we know whether anybody actually needs this, maybe it's better to avoid gratuitous complexity, both in terms of protocol operation, testing (yet another thing a mapping protocol has to test) and user agents. Henning On Feb 15, 2006, at 6:52 PM, Gunnar Hellstrom wrote: > What would sos.police.tty do and how would it be invoked? > > If it could lead to a text capable IP terminal, it should be called > sos.police.real-time-text or so. > > If it helps to find a PSTN based PSAP with text capabilities, it > could be called sos.police.txp > > tty is a US term. > > Gunnar > > ---------------------------------------------------------------------- > ------- > Gunnar Hellström, Omnitor > gunnar.hellstrom@omnitor.se > Mob: +46 708 204 288 > Phone: +46 8 556 002 03 > www.omnitor.se > -----Original Message----- > From: Brian Rosen [mailto:br@brianrosen.net] > Sent: Thursday, February 16, 2006 12:17 AM > To: 'Gunnar Hellstrom'; ecrit@ietf.org; 'Aquil, Kamran'; 'François > D. Ménard' > Cc: 'Gregg Vanderheiden' > Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls > > All I get out of this for ecrit is that we need entries for > sos.police.tty in the service registry > > > > Brian > > > > From: Gunnar Hellstrom [mailto:gunnar.hellstrom@omnitor.se] > Sent: Wednesday, February 15, 2006 5:47 PM > To: ecrit@ietf.org; 'Aquil, Kamran'; br@brianrosen.net; François D. > Ménard > Cc: Gregg Vanderheiden > Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls > > > > It is quite widely accepted now that real-time text transmitted > with its own text coded RTP payload RFC 4103 is used to carry text > that may be gatewayed to/from TTY/TDD/textphones in PSTN. > > > > It is discussed in http://www.ietf.org/internet-drafts/draft-ietf- > sipping-toip-03.txt > > > > And it is documented in http://www.ietf.org/internet-drafts/draft- > sinnreich-sipdev-req-08.txt > > > > Also other standardisation bodies have picked up the real-time text > concept in IP networks, and pointed at RFC 4103 (or its compatible > predecessor RFC2793 ). E.g. 3GPP and ETSI. > > A couple of years ago we had an intensive discussion in the SIMPLE > mail list about the possibility to use MSRP to carry the real-time > text medium, but we concluded that it would cause too much overhead > or too much delay for the users, so that RTP was recommended > instead. The most common use of MSRP is to not transmit until end > of sentence, while for real time text, transmission is required > with at most 500 ms interval as long as there is anything to > transmit in order to maintain the real-time feeling of being in > touch in a conversation through this medium. > > > > Quite commonly you will connect a text RTP stream and an audio RTP > stream and possibly a video RTP stream in the same call, so that > you will get an enhanced multimedia phone call with all supported > media > > > > The ecrit requirements also mentions this correspondence > > in www.ietf.org/internet-drafts/draft-ietf-ecrit-requirements-03.txt > > > Re4. Multiple Modes: Multiple communication modes, such as audio, > video and text messaging MUST be supported. > > Motivation: In PSTN, voice and text telephony (often called > TTY or > textphone in North America) are the only commonly supported > media. > Emergency calling must support a variety of media. Such media > should include voice, conversational text (RFC 4103 [9]), > instant > messaging and video. > > > > I am working in a European group where one of the goals is to agree > on handling text users' requirements on emergency calling in IP > networks. Of course we want to agree on global solutions if possible. > > > > Address mapping is one important and tricky question for text > users. It is true that different countries have different > approaches on emergency calling with PSTN Text telephones (TTYs). > Some have the same number as voice users, while others have > specific numbers. On the SIP side it would be good to have the same > URL and make any required routing based on declared media, mode and > language capabilities and preferences. > > > > Text capable gateways are not at all as common as VoIP gateways, so > if the PSAP is still in PSTN, there is a need to have a good > mechanism for routing emergency calls from SIP into PSTN through a > text capable gateway. I cannot say that the mechanisms for finding > the right gateway and make the proper address mapping to a PSTN > number is solved yet for the text calls, and it would be excellent > if we could have that topic in mind in the discussions and get > proper methods documented. > > > > I have drafted, but not yet submitted a registration of a SIP URL > and an ENUM subservice for real-time text. It might be helpful for > finding text gateways and mapping addresses and (text) numbers, but > I would like to see some scenarios thoroughly discussed before > adding SIP URL and another ENUM subservice. > > > > Would there be any benefit of being allowed to enter TXP:112 or > having ENUM to find an appropriate address if I call 112 from a > SIP multimedia phone declaring text capabilities with m=text in sdp? > > > > > > Gunnar > > ---------------------------------------------------------------------- > ------- > > Gunnar Hellström, Omnitor > > gunnar.hellstrom@omnitor.se > > -----Original Message----- > From: ecrit-bounces@ietf.org [mailto:ecrit-bounces@ietf.org]On > Behalf Of François D. Ménard > Sent: Wednesday, February 15, 2006 5:14 PM > To: br@brianrosen.net; 'Aquil, Kamran'; ecrit@ietf.org > Subject: Re: [Ecrit] ECRIT support for TTY/TDD calls > > > I made a contribution to CISC NTWG on use of SIP for transporting > TDD traffic: > > http://www.crtc.gc.ca/cisc/COMMITTE/N-docs/NTCO0338.doc > > I think it may be relevant to ECRIT. > > -=Francois=- > > > On 2/15/06 10:51 AM, "Brian Rosen" <br@brianrosen.net> wrote: > > Within the scope of our work, I don't see how TDD services are > impacted until we get to the architecture effort, which probably > has to have some sections on that subject. > With respect to the mapping protocol, I do not believe there is any > impact at all. > With respect to the sos service urn, I do not believe there is any > impact at all > > Ecrit doesn't have scope to talk about any kind of gateways or > codec support. > > Ah! My BCP on phones and proxies may need some mention, although > this is the IETF, and I don't think the ploy of forcing the entire > PSTN to support TDD just so 9-1-1 TDD will work. That effort would > have to be in the general SIP arena. > > Brian > > > From: ecrit-bounces@ietf.org [mailto:ecrit-bounces@ietf.org] On > Behalf Of Aquil, Kamran > Sent: Wednesday, February 15, 2006 10:31 AM > To: ecrit@ietf.org > Subject: [Ecrit] ECRIT support for TTY/TDD calls > > > Folks, > > > > Like to know if there are specific ECRIT requirements recognizing > support for Telecommunications Device for the Deaf (TDD) services > for the hearing impaired. If not is this left for VOIP/SIP gateways > to perform this requirement of translating the TDD calls to Text > and Speech encoding. Wanted to make sure how ECRIT meet requirement > for TDD services. > > > > Regards, > Kamran Aquil > Intelligent Transportation Systems- Division > Mitretek Systems. > > > > > > _______________________________________________ > Ecrit mailing list > Ecrit@ietf.org > https://www1.ietf.org/mailman/listinfo/ecrit > > > > -- > Francois D. Menard > fmenard@xittelecom.com > > > _______________________________________________ > Ecrit mailing list > Ecrit@ietf.org > https://www1.ietf.org/mailman/listinfo/ecrit ------------------------------ Message: 3 Date: Wed, 15 Feb 2006 21:18:03 EST From: Rockford9@aol.com Subject: Re: [Ecrit] ECRIT support for TTY/TDD calls To: mlinsner@cisco.com, br@brianrosen.net, gunnar.hellstrom@omnitor.se, ecrit@ietf.org, kamran.aquil@mitretek.org, fmenard@xittelecom.com Cc: gv@trace.wisc.edu Message-ID: <75.55537d35.31253adb@aol.com> Content-Type: text/plain; charset="utf-8" I have a question on what is being discussed. Are you only discussing TTY/TDD devices used via PSTN specifically by deaf to access emergency services? Wanting to clarify that you are not discussing any text user access beyond that, since that could be used by anyone to access emergency services and so should have no special TTY/TDD type handling. Thanks for assistance. Rick Jones In a message dated 2/15/2006 7:47:33 PM Eastern Standard Time, mlinsner@cisco.com writes: So the UA must know this? Not the proxy...? -Marc- ____________________________________ From: ecrit-bounces@ietf.org [mailto:ecrit-bounces@ietf.org] On Behalf Of Brian Rosen Sent: Wednesday, February 15, 2006 6:17 PM To: 'Gunnar Hellstrom'; ecrit@ietf.org; 'Aquil, Kamran'; 'François D. Ménard' Cc: 'Gregg Vanderheiden' Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls All I get out of this for ecrit is that we need entries for sos.police.tty in the service registry Brian ____________________________________ From: Gunnar Hellstrom [mailto:gunnar.hellstrom@omnitor.se] Sent: Wednesday, February 15, 2006 5:47 PM To: ecrit@ietf.org; 'Aquil, Kamran'; br@brianrosen.net; François D. Ménard Cc: Gregg Vanderheiden Subject: RE: [Ecrit] ECRIT support for TTY/TDD calls It is quite widely accepted now that real-time text transmitted with its own text coded RTP payload RFC 4103 is used to carry text that may be gatewayed to/from TTY/TDD/textphones in PSTN. It is discussed in _http://www.ietf.org/internet-drafts/draft-ietf-sipping-toip-03.txt_ (http://www.ietf.org/internet-drafts/draft-ietf-sipping-toip-03.txt) And it is documented in _http://www.ietf.org/internet-drafts/draft-sinnreich-sipdev-req-08.txt_ (http://www.ietf.org/internet-drafts/draft-sinnreich-sipdev-req-08.txt) Also other standardisation bodies have picked up the real-time text concept in IP networks, and pointed at RFC 4103 (or its compatible predecessor RFC2793 ). E.g. 3GPP and ETSI. A couple of years ago we had an intensive discussion in the SIMPLE mail list about the possibility to use MSRP to carry the real-time text medium, but we concluded that it would cause too much overhead or too much delay for the users, so that RTP was recommended instead. The most common use of MSRP is to not transmit until end of sentence, while for real time text, transmission is required with at most 500 ms interval as long as there is anything to transmit in order to maintain the real-time feeling of being in touch in a conversation through this medium. Quite commonly you will connect a text RTP stream and an audio RTP stream and possibly a video RTP stream in the same call, so that you will get an enhanced multimedia phone call with all supported media The ecrit requirements also mentions this correspondence in _www.ietf.org/internet-drafts/draft-ietf-ecrit-requirements-03.txt_ (http://www.ietf.org/internet-drafts/draft-ietf-ecrit-requirements-03.txt) Re4. Multiple Modes: Multiple communication modes, such as audio, video and text messaging MUST be supported. Motivation: In PSTN, voice and text telephony (often called TTY or textphone in North America) are the only commonly supported media. Emergency calling must support a variety of media. Such media should include voice, conversational text (RFC 4103 [9]), instant messaging and video. I am working in a European group where one of the goals is to agree on handling text users' requirements on emergency calling in IP networks. Of course we want to agree on global solutions if possible. Address mapping is one important and tricky question for text users. It is true that different countries have different approaches on emergency calling with PSTN Text telephones (TTYs). Some have the same number as voice users, while others have specific numbers. On the SIP side it would be good to have the same URL and make any required routing based on declared media, mode and language capabilities and preferences. Text capable gateways are not at all as common as VoIP gateways, so if the PSAP is still in PSTN, there is a need to have a good mechanism for routing emergency calls from SIP into PSTN through a text capable gateway. I cannot say that the mechanisms for finding the right gateway and make the proper address mapping to a PSTN number is solved yet for the text calls, and it would be excellent if we could have that topic in mind in the discussions and get proper methods documented. I have drafted, but not yet submitted a registration of a SIP URL and an ENUM subservice for real-time text. It might be helpful for finding text gateways and mapping addresses and (text) numbers, but I would like to see some scenarios thoroughly discussed before adding SIP URL and another ENUM subservice. Would there be any benefit of being allowed to enter TXP:112 or having ENUM to find an appropriate address if I call 112 from a SIP multimedia phone declaring text capabilities with m=text in sdp? Gunnar ----------------------------------------------------------------------------- Gunnar Hellström, Omnitor _gunnar.hellstrom@omnitor.se_ (mailto:gunnar.hellstrom@omnitor.se) -----Original Message----- From: ecrit-bounces@ietf.org [mailto:ecrit-bounces@ietf.org]On Behalf Of François D. Ménard Sent: Wednesday, February 15, 2006 5:14 PM To: br@brianrosen.net; 'Aquil, Kamran'; ecrit@ietf.org Subject: Re: [Ecrit] ECRIT support for TTY/TDD calls I made a contribution to CISC NTWG on use of SIP for transporting TDD traffic: _http://www.crtc.gc.ca/cisc/COMMITTE/N-docs/NTCO0338.doc_ (http://www.crtc.gc.ca/cisc/COMMITTE/N-docs/NTCO0338.doc) I think it may be relevant to ECRIT. -=Francois=- On 2/15/06 10:51 AM, "Brian Rosen" <br@brianrosen.net> wrote: Within the scope of our work, I donâEUR(tm)t see how TDD services are impacted until we get to the architecture effort, which probably has to have some sections on that subject. With respect to the mapping protocol, I do not believe there is any impact at all. With respect to the sos service urn, I do not believe there is any impact at all Ecrit doesnâEUR(tm)t have scope to talk about any kind of gateways or codec support. Ah! My BCP on phones and proxies may need some mention, although this is the IETF, and I donâEUR(tm)t think the ploy of forcing the entire PSTN to support TDD just so 9-1-1 TDD will work. That effort would have to be in the general SIP arena. Brian ____________________________________ From: ecrit-bounces@ietf.org [_mailto:ecrit-bounces@ietf.org]_ (mailto:ecrit-bounces@ietf.org]) On Behalf Of Aquil, Kamran Sent: Wednesday, February 15, 2006 10:31 AM To: ecrit@ietf.org Subject: [Ecrit] ECRIT support for TTY/TDD calls Folks, Like to know if there are specific ECRIT requirements recognizing support for Telecommunications Device for the Deaf (TDD) services for the hearing impaired. If not is this left for VOIP/SIP gateways to perform this requirement of translating the TDD calls to Text and Speech encoding. Wanted to make sure how ECRIT meet requirement for TDD services. Regards, Kamran Aquil Intelligent Transportation Systems- Division Mitretek Systems. ____________________________________ _______________________________________________ Ecrit mailing list Ecrit@ietf.org https://www1.ietf.org/mailman/listinfo/ecrit -- Francois D. Menard fmenard@xittelecom.com _______________________________________________ Ecrit mailing list Ecrit@ietf.org https://www1.ietf.org/mailman/listinfo/ecrit -------------- next part -------------- An HTML attachment was scrubbed... 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- [Ecrit] Re: Ecrit Digest, Vol 13, Issue 20 Hansen, Jenny <Contractor>