Subject: [AVT] comments on RFC2833bisdata-08

From: "Aleksandar Lebl" <[email-masked]>
Date: Mon, 10 Jul 2006 10:00:11 +0200

Hi all,

according to RFC2833bisdata-08, we consider data transmission 

for telephone subscriber informing over local loop, as, for example, 

transmission of caller ID. This transmission is done according to 

ETSI recommendations EN 300 659-1, EN 300 659-2 and 

EN 300 659-3 (former ETS 300 659-1 and ETS 300 659-2), 

using FSK signaling. We think that it can be necessary to send these 

signals accross Internet.

According to EN 300 659-1, there are seven scenarios of data 

transmission in the on-hook state, four of them are data transmission 

associated with ringing and three of them are data transmission not 

associated with ringing. According to EN 300 659-2 there is one 

scenario of data transmission in the off-hook state.

For on-hook scenarios seven possibilities of data transmission are:

1. after first ring pattern (in the gap between first and second ring 

pattern)

2. before the first ring pattern with dual tone allerting signal 

(DT-AS: 2130Hz and 2750Hz) preceding the data transmission

3. before the first ring pattern with ringing pulse allerting signal 

(RP-AS) preceding the data transmission

4. before the first ring pattern with line polarity reversal and 

DT-AS preceding the data transmission

5. not associated with ringing with DT-AS preceding the data 

transmission

6. not associated with ringing with RP-AS preceding the data 

transmission

7. not associated with ringing with line polarity reversal and 

DT-AS preceding the data transmission.

We suggest to introduce seven new event codes for these 

scenarios. Four of them which consider data transmission 

associated with ringing can be in the free space after ring

event 89 and the three of them which deals with data transmission 

not associated with ringing can be placed after the last code 211.

For off-hook scenario(s) the sending procedure is:

a) line equipment (LE) in the exchange stops sending voice signal

b) LE sends DT-AS

c) terminal equipment (TE) sends DTMF digit D

d) LE sends data

e) LE establishes voice path again

We can revive the event code 87 for DT-AS, which is mentioned 

in the first version of RFC2833 for DT-AS, for this situation. Also 

we need to revive codes 64 and 65 for off-hook and on-hook situation.

According to this discussion, we suggest following codes:

90 - data transmission in the first long silent period between two ring 

patterns (point 6.1.1. in EN 300 659-1)

91 - data transmission before the first ring pattern with Dual Tone 

Alerting Signal (DT-AS) (point 6.1.2.a) in EN 300 659-1) 

92 - data transmission before the first ring pattern with Ringing Pulse 

Alerting Signal (RP-AS) (point 6.1.2.b) in EN 300 659-1)

93 - data transmission before the first ring pattern with a line reversal 

followed by a DT-AS (LR-DT-AS) (point 6.1.2.c) in EN 300 659-1) 

212 - data transmission not associated with ringing using DT-AS 

(point 6.2.a) in EN 300 659-1)

213 - data transmission not associated with ringing using RP-AS 

(point 6.2.b) in EN 300 659-1)

214 - data transmission not asspciated with ringing using LR-DT-AS 

(point 6.2.c) in EN 300 659-1)

                                             Zarko Markov and

                                             Aleksandar Lebl

_______________________________________________
Audio/Video Transport Working Group
[email-masked]
https://www1.ietf.org/mailman/listinfo/avt

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From: "Tom-PT Taylor" <[email-masked]>
Date: Mon, 10 Jul 2006 09:29:42 -0400

RFC2833bisdata has now been approved by the IESG and cannot be changed. 
For additional event codes you will need to write a new Internet Draft. 
You may want to think about what other events you need related to line 
signalling, that you might want to include in this draft.

Aleksandar Lebl wrote:
> ------------------------------------------------------------------------
>

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From: [email-masked]
Date: Wed, 12 Jul 2006 18:37:37 +0200

Aleksander,

for "PSTN supplementary service" signalling over RTP could be also
following alternatives of interest:
      V.23-over-VBDoIP (e.g. V.23-over-G.711/RTPoIP) according ITU-T V.152
      in case of V.23 transmission mode, or
      DTMF-over-G.711/RTPoIP in case of DTMF transmission mode
of EN 300 659.
This is a much simpler approach (e.g. because there isn't any detection
process on circuit side, and mapping process of PSTN supplementary service
signalling on RFC2833 events required), and applicable for many IP networks
("the data speed is rather low here, making the transmission significantly
robust for a certain level of IP packet loss ...").

- Albrecht

                      "Tom-PT Taylor"                                                                                             
                      <[email-masked]         To:      Aleksandar Lebl <[email-masked]>                                         
                      om>                      cc:      [email-masked]                                                              
                                               Subject: Re: [AVT] comments on RFC2833bisdata-08                                   
                      10.07.2006 15:29