One document matched: draft-ietf-megaco-fmtdeterm-00.txt
Internet Engineering Task Force Roy Spitzer(Editor)
INTERNET DRAFT Telogy
<draft-ietf-megaco-fmtdeterm-00.txt> Zacharias Bilalis (Editor)
Category: Standards Track (?) Siemens
Expires: August 1, 2000
Contributions from:
Gunnar Hellstrom Omnitor
James Rafferty Brooktrout Technology
Glenn Parsons Nortel Networks
Fax, Modem, Text Telephone Determination using Megaco/H.248
STATUS OF THIS MEMO
This document is an Internet-Draft and is in full conformance with all
provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering Task
Force (IETF), its areas, and its working groups. Note that other groups
may also distribute working documents as Internet- Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet- Drafts as reference material
or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
ABSTRACT
This document discusses the dynamic determination of
Voice/Modem/FAX/Text Telephone over a single port using Megaco and
refers to the packages described for Megaco. The document aims to become
an Appendix to Megaco and to be the base for the "application guide".
TABLE OF CONTENTS
Spitzer, Bilalis [Page 1]
Internet draft F, M, T Determination February 1, 2000
1. Introduction .. .. .. .. .. .. .. .. .. .. .. .. .. .. 2
2. Relay Ports supporting V.8 .. .. .. .. .. .. .. .. .. .. 2
3. Relay Ports for V.21 .. .. .. .. .. .. .. .. .. .. .. .. 10
4. References .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 10
1. Introduction
This document discusses the dynamic determination of
Voice/Modem/FAX/Text Telephone over a single port using Megaco and
refers to the packages described for Megaco. The document aims to become
an Appendix to Megaco and to be the base for the "application guide".
2 Relay Ports supporting V.8
Spitzer, Bilalis [Page 2]
Internet draft F, M, T Determination February 1, 2000
Termination T1 MGC Termination T2
|<-ctx=NULL,MODify(T1)-------| |
|--Resp--------------------->| |
|<-Audit(capabilities)-------| |
|--Resp(codecs)------------->| |
off- | | |
hook |--Notify(offhook)---------->| |
|<-Resp----------------------| |
Accumulate | |
Digits|--Notify(number)----------->| |
| |--Audit(capabilities)------>|
|<-Resp----------------------| |
| |<--Resp(codecs)-------------|
|<-ADD CTX(T1,selectCODEC)---| |
| |--ADD CTX(T2,select CODEC)->|
|--Resp--------------------->| |
| |<--Resp---------------------|
| |--MOD CTX(T2,Sig=ring)----->|
|<-MOD CTX(T1,Sig=ringback)--| |RING
Ringback |<-Resp----------------------|
Tone |--Resp--------------------->| |off-
| |<-Notify(offhook)-----------|hook
|<-MOD CTX(T1,Mode=sendrecv)-| |
| |--Resp--------------------->|
|--Resp--------------------->| |
+------------------------------------------------------------------+
| Voice may be transferred between T1 and T2 |
+------------------------------------------------------------------+
CNG | | |
|--Notify(dtone=CNG)-------->| |
| |--MOD CTX(T2,Sig=CNG)------>|
|<-Resp----------------------| |CNG
| |<-Resp----------------------|
| | |CED
| |<-Notify(dtone=CED)---------|
|<-MOD CTX(T1,Sig=CED)-------| |
CED | |--Resp--------------------->|
|--Resp--------------------->| |
| |-MOD CTX(T2,selectFAXCODEC)>|
| | |load
| |<-Resp----------------------|CODEC
|<MOD CTX(T1,selectFAXCODEC)-| |
load | | |
CODEC|--Resp--------------------->| |
| | |V.21
| |<-Notify(dtone=V21flag)-----|flags
Spitzer, Bilalis [Page 3]
Internet draft F, M, T Determination February 1, 2000
|<-MOD CTX(T1,Sig=V21flag)---| |
| |--Resp--------------------->|
|--Resp--------------------->| |
| | |V.21
| | |flags
+------------------------------------------------------------------+
| Start FAX Communications |
+------------------------------------------------------------------+
Voice to FAX Call with modem or Text Telephone Call possible
(Termination on Media Gateway) - Switchover based on CED/ANS detection
Figure 1. Switch to FAX based on CNG and CED
If CNG and CED are detected, the MGC should switch to the FAX codec. If
the CNG is not used for switching, a flow similar to Figure 2 can be
used.
Spitzer, Bilalis [Page 4]
Internet draft F, M, T Determination February 1, 2000
Termination T1 MGC Termination T2
|<-ctx=NULL,MODify(T1)-------| |
|--Resp--------------------->| |
|<-Audit(capabilities)-------| |
|--Resp(codecs)------------->| |
off- | | |
hook |--Notify(offhook)---------->| |
|<-Resp----------------------| |
Accumulate | |
Digits|--Notify(number)----------->| |
| |--Audit(capabilities)------>|
|<-Resp----------------------| |
| |<--Resp(codecs)-------------|
|<-ADD CTX(T1,selectCODEC)---| |
| |--ADD CTX(T2,select CODEC)->|
|--Resp--------------------->| |
| |<--Resp---------------------|
| |--MOD CTX(T2,Sig=ring)----->|
|<-MOD CTX(T1,Sig=ringback)--| |RING
Ringback |<-Resp----------------------|
Tone |--Resp--------------------->| |off-
| |<-Notify(offhook)-----------|hook
|<-MOD CTX(T1,Mode=sendrecv)-| |
| |--Resp--------------------->|
|--Resp--------------------->| |
+------------------------------------------------------------------+
| Voice may be transferred between T1 and T2 |
+------------------------------------------------------------------+
CNG not seen or not sent | |
| | |
| | |
| | |
| | |CED/
| |<-Notify(dtone=CED/ANS)-----|ANS
|<-MOD CTX(T1,Sig=CED/ANS)---| |
CED | |--Resp--------------------->|
|--Resp--------------------->| |
| |-MOD CTX(T2,selTextTelCODEC>|
| | |load
| |<-Resp----------------------|CODEC
|<MOD CTX(T1,selTextTelCODEC-| |
load | | |
CODEC|--Resp--------------------->| |
| | |V.21
| |<-Notify(dtone=V21flag)-----|flags
|<-MOD CTX(T1,Sig=V21flag)---| |
Spitzer, Bilalis [Page 5]
Internet draft F, M, T Determination February 1, 2000
| |--Resp--------------------->|
|--Resp--------------------->| |
| |-MOD CTX(T2,selectFAXCODEC)>|
|<-MOD CTX(T1,selFAXCODEC)---| |load
| |<-Resp----------------------|CODEC
load | | |
CODEC|--Resp--------------------->| |
| | |V.21
| |<-Notify(dtone=V21flag)-----|flags
|<-MOD CTX(T1,Sig=V21flag)---| |
| |--Resp--------------------->|
|--Resp--------------------->| |
+------------------------------------------------------------------+
| Start FAX Communications |
+------------------------------------------------------------------+
Voice to FAX Call with modem or Text Telephone Call possible
(Termination on Media Gateway) - Switchover based on CED/ANS detection,
FAX switchover based on V.21 flag detection
Figure 2. Switch to FAX based on V.21 Flags
A CI tone may be sent prior to the CED/ANS tone.
Spitzer, Bilalis [Page 6]
Internet draft F, M, T Determination February 1, 2000
Termination T1 MGC Termination T2
|<-ctx=NULL,MODify(T1)-------| |
|--Resp--------------------->| |
|<-Audit(capabilities)-------| |
|--Resp(codecs)------------->| |
off- | | |
hook |--Notify(offhook)---------->| |
|<-Resp----------------------| |
Accumulate | |
Digits|--Notify(number)----------->| |
| |--Audit(capabilities)------>|
|<-Resp----------------------| |
| |<--Resp(codecs)-------------|
|<-ADD CTX(T1,selectCODEC)---| |
| |--ADD CTX(T2,select CODEC)->|
|--Resp--------------------->| |
| |<--Resp---------------------|
| |--MOD CTX(T2,Sig=ring)----->|
|<-MOD CTX(T1,Sig=ringback)--| |RING
Ringback |<-Resp----------------------|
Tone |--Resp------------------->--| |off-
| |<-Notify(offhook)-----------|hook
|<-MOD CTX(T1,Mode=sendrecv)-| |
| |--Resp--------------------->|
|--Resp--------------------->| |
+------------------------------------------------------------------+
| Voice may be transferred between T1 and T2 |
+------------------------------------------------------------------+
CI | | |
|-Notify(MdmToneEvent=CI)--->| |
| |--MOD CTX(T2, Sig=CI)------>|
|<-Resp----------------------| | CI
| |<-Resp----------------------|
| | |CED/
| |<-Notify(dtone=ANS)---------|ANS
|<-MOD CTX(T1,Sig=ANS)------>|
ANS | |--Resp--------------------->|
|--Resp--------------------->| |
| |-MOD CTX(T1,selTextTelCODEC>|
| | |load
| |<-Resp----------------------|CODEC
|<MOD CTX(T1,selTextTelCODEC-| |
load | | |
CODEC|--Resp--------------------->| |
| | |CM
| |<-Notify(MdmToneEvent=CM)---|
Spitzer, Bilalis [Page 7]
Internet draft F, M, T Determination February 1, 2000
|<-MOD CTX(T1,Sig=CM)--------| |
CM | |--Resp--------------------->|
|--Resp--------------------->| |
| |-MOD CTX(T2,selModemCODEC)->|
|<-MOD CTX(T1,selModemCODEC)-| |load
| |<-Resp----------------------|CODEC
load | | |
CODEC|--Resp--------------------->| |
| | |CM
| |<-Notify(MdmToneEvent=CM)---|
|<-MOD CTX(T1,Sig=CM)--------| |
CM | |--Resp--------------------->|
|--Resp--------------------->| |
+------------------------------------------------------------------+
| Start Modem Communications |
+------------------------------------------------------------------+
Voice to Modem Call with FAX or Text Telephone Call possible
(Termination on Media Gateway) - Switchover based on CED/ANS detection
Figure 3. Modem Determination Based on ANS and CM
Spitzer, Bilalis [Page 8]
Internet draft F, M, T Determination February 1, 2000
Termination T1 MGC Termination T2
|<-ctx=NULL,MODify(T1)-------| |
|--Resp--------------------->| |
|<-Audit(capabilities)-------| |
|--Resp(codecs)------------->| |
off- | | |
hook |--Notify(offhook)---------->| |
|<-Resp----------------------| |
Accumulate | |
Digits|--Notify(number)----------->| |
| |--Audit(capabilities)------>|
|<-Resp----------------------| |
| |<--Resp(codecs)-------------|
|<-ADD CTX(T1,selectCODEC)---| |
| |--ADD CTX(T2,select CODEC)->|
|--Resp--------------------->| |
| |<--Resp---------------------|
| |--MOD CTX(T2,Sig=ring)----->|
|<-MOD CTX(T1,Sig=ringback)--| |RING
Ringback |<-Resp----------------------|
Tone |--Resp------------------->--| |off-
| |<-Notify(offhook)-----------|hook
|<-MOD CTX(T1,Mode=sendrecv)-| |
| |--Resp--------------------->|
|--Resp--------------------->| |
+------------------------------------------------------------------+
| Voice may be transferred between T1 and T2 |
+------------------------------------------------------------------+
CI | | |
|-Notify(TextPhoneSig=CIV18)>| |
| |--MOD CTX(T2, Sig=CIV18)--->|
|<-Resp----------------------| | CI
| |<-Resp----------------------|
| | |ANS
| |<-Notify(dtone=ANS)---------|
|<-MOD CTX(T1,Sig=ANS)------>|
ANS | |--Resp--------------------->|
|--Resp--------------------->| |
| |-MOD CTX(T2,selTextTelCODEC>|
| | |load
| |<-Resp----------------------|CODEC
|<MOD CTX(T1,selTextTelCODEC-| |
load | | |
CODEC|--Resp--------------------->| |
| | |
TXP | | |
Spitzer, Bilalis [Page 9]
Internet draft F, M, T Determination February 1, 2000
|--Notify(TextPhoneSig=TXP)->| |
| |-MOD CTX(T2,Sig=TXP)------->|
| |<-Resp----------------------|
|<-Resp----------------------| |
+------------------------------------------------------------------+
| Start Text Telephone Communications |
+------------------------------------------------------------------+
Voice to Text Telephone Call with FAX or Modem Call possible
(Termination on Media Gateway) - Switchover based on CED/ANS detection
Figure 4. Text Telephone Determination
3 Relay Ports for V.21
TBD
4 References
[1] ITU-T Recommendation T.30 (7/96) Procedures for document facsimile
transmission in the general switched telephone network.
[2] ITU-T Recommendation V.8 Procedures for starting sessions of data
transmission over the public switched telephone network
[3] ITU-T Recommendation V.8 bis Procedures for the identification and
selection of common modes of operation between data circuit-
termination equipment (DCEs).
[4] ITU-T Recommendation V.18 Operational and interworking requirements
for DCES operating in the text telephone mode.
[5] ITU-T Recommendation V.25 Automatic answering equipment and/or
parallel automatic calling equipment on the general switched tele-
phone network.
[6] ITU-T Recommendation V.21 (11/88) - 300 bits per second duplex
modem standardized for use in the general switched telephone net-
work
tbl *.txt | nroff -ms | col -bx | f.pl > out
Spitzer, Bilalis [Page 10]
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