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[rob.dyck at telus.net]

If RBS means robbed bit signalling then it is transmitted in the media bit
stream but as the name implies it is not used for media. If I remember
correctly the LSB from every sixth frame is robbed leaving 7 bits and 1 faked
which would probably be correct about 50% of the time. RBS introduces a small
amount of distortion. The channel bank will use the state of the signalling
bit to set the M lead (on or offhook ) of the appropriate channel. The E lead
sets the signalling bit for the other direction. Think Ear and Mouth.

MF of course is encoded into the bit stream the same as any other audio
source. To avoid RBS, on/offhook can be transmitted using SF ( 2600 HZ ) in
band. You would want to disable RBS in that case. Compatible equipment is
required obviously.

On Thursday 21 August 2008, Brian West wrote:

[msc at freeswitch.org]

BTW,

I happen to have both a line side and a trunk side T1 card for my NEC
2400 PBX. I've done this sort of thing with asterisk and it worked
pretty well. Please let me know when you are ready for someone to do
some testing.

-MC

Sent from my iPhone

On Aug 21, 2008, at 8:08 PM, Robert Dyck <rob.dyck@telus.net> wrote:

[hockd at dteenergy.com]

Rob I believe you have the grasp of RBS. It has nothing to do with MF or the type of signaling per se but rather the encoding of the signaling as you have described it here.

Dennis Hock

-----freeswitch-users-bounces@lists.freeswitch.org wrote: -----

[rob.dyck at telus.net]

I messed up. The E lead receives signalling whereas the M lead is used to send
to the far end.

On Friday 22 August 2008, Dennis D Hock wrote:

[hockd at dteenergy.com]

I reread your post and you are correct. been a long time for me working with E&M guess I am getting old as I didn't recognize what you had said until I reread it.

Easy enough to Google it or if a person has access to almost any copy of the "Notes on the Networks". A good description is included in any version of that documenrt as well as other places.

Take care,

Dennis Hock

-----Robert Dyck <rob.dyck@telus.net> wrote: -----

[mcollins at fcnetwork.com]

FYI,

I have a copy of Matthew Gast’s T1 – A Survival Guide and it goes over all this stuff pretty well.
-MC


From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Dennis D Hock
Sent: Friday, August 22, 2008 8:50 AM
To: Robert Dyck
Cc: freeswitch-users@lists.freeswitch.org
Subject: Re: [Freeswitch-users] T1 RBS Support Revisited


I reread your post and you are correct. been a long time for me working with E&M guess I am getting old as I didn't recognize what you had said until I reread it.



Easy enough to Google it or if a person has access to almost any copy of the "Notes on the Networks". A good description is included in any version of that documenrt as well as other places.



Take care,


Dennis Hock

-----Robert Dyck <rob.dyck@telus.net> wrote: -----
To: freeswitch-users@lists.freeswitch.org
From: Robert Dyck <rob.dyck@telus.net>
Date: 08/22/2008 11:40AM
cc: Dennis D Hock <hockd@dteenergy.com>
Subject: Re: [Freeswitch-users] T1 RBS Support Revisited

I messed up. The E lead receives signalling whereas the M lead is used to send
to the far end.

On Friday 22 August 2008, Dennis D Hock wrote: