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FAX handling with Lync RRS feed

  • Question

  • Hello all,

    I'm trying to plan migration of our telephony services to Lync using SIP trunks.

    • We have 51 fax machines
    • We dont want to use any analog lines, but only SIP trunks

    I understand that a few SIP trunk providers have started supporting fax over SIP trunks but am trying to understand how this is done. After going through this blog - http://www.sebastian-grewing.de/2011/03/23/fax-t-38-integration-with-lync/  I'm assuming that we'll need a T38 enabled SIP gateway.

    Am I correct ?

    If yes, in that case, do I need 2 SIP trunks, one for audio/video and another one for Fax ? or is it just one sip trunk and we set the gateway to receive / send the fax calls ?

     

    thanks in advance

    • Moved by Sharon.Shen Monday, August 8, 2011 7:49 AM (From:Planning and Deployment)
    Friday, August 5, 2011 10:13 AM

Answers

  •  

    That is going to depend upon the SIP trunk provider.  Generally speaking, it would not be two seperate trunks - but here is the catch.  On the blog you reference there are two methods:

    1- Media Bypass

    2 - Lync Bypass

    The "Lync Bypass" method on the diagram infers that you have a seperate trunk just for FAX.   If you didn't want to do this, you could program your border gateway to divert partcular incomming numbers straight to the fax machine ATAs  That would make the digram look a little different, putting the border gateway in front of the mediation server (use as an "SBC").

    Let me just say, I don't agree with the diagrams on that blog entry.


    Thomas Kisner, MCITP -- http://thelync.net
    • Proposed as answer by Sharon.Shen Monday, August 8, 2011 7:59 AM
    • Marked as answer by Sharon.Shen Thursday, August 25, 2011 2:10 AM
    Friday, August 5, 2011 10:52 PM

All replies

  •  

    That is going to depend upon the SIP trunk provider.  Generally speaking, it would not be two seperate trunks - but here is the catch.  On the blog you reference there are two methods:

    1- Media Bypass

    2 - Lync Bypass

    The "Lync Bypass" method on the diagram infers that you have a seperate trunk just for FAX.   If you didn't want to do this, you could program your border gateway to divert partcular incomming numbers straight to the fax machine ATAs  That would make the digram look a little different, putting the border gateway in front of the mediation server (use as an "SBC").

    Let me just say, I don't agree with the diagrams on that blog entry.


    Thomas Kisner, MCITP -- http://thelync.net
    • Proposed as answer by Sharon.Shen Monday, August 8, 2011 7:59 AM
    • Marked as answer by Sharon.Shen Thursday, August 25, 2011 2:10 AM
    Friday, August 5, 2011 10:52 PM
  • Many thanks for the response.

    Very general question then - how can inbound and outbound faxing be acheived then in an environment with lync, exchange and sharepoint 2010 (bascially a microsoft house) ?

     

    Tx

    Monday, August 8, 2011 11:05 AM
  • That's a very complicated question.  You need to narrow it down, I think.

    We are using "Lync Bypass" - the PSTN gateway sends FAX traffic directly to the fax machine ATAs, and vice-versa, completely bypassing the Lync servers.

    This bit from MS says "Fax devices must be connected to a gateway with PSTN connectivity for inbound and outbound calls" ( http://64.4.11.252/en-us/library/gg398314.aspx ), but I am not sure exactly what that means.  I infer that it works best when the fax machines are wired into the PSTN gateway itself, rather that a separate ATA box.

    Tuesday, August 9, 2011 6:21 PM
  • Thanks John.

    Hmm... PSTN gateway.... One of my objectives is to remove dependency on 'copper' completely. Hence since I read about FoIP, Faxing through SIP Trunks etc, I was thinking of going down that route. Hence the question.

    Wednesday, August 10, 2011 2:49 PM
  • Good luck with that.

    Copper is reliable.  VoIP, not so much.

    Thursday, August 11, 2011 5:56 PM
  • Hello, please feel free to join the premier linkedin group on Fax with industry leaders from telcos, and fax providers to also find answers. Post up accordingly. 

    the group is named Fax over IP http://www.linkedin.com/groups/Fax-over-IP-1775302?goback=%2Egde_1775302_member_102589654


    Scott Salisbury

    Wednesday, March 21, 2012 2:46 PM
  • UCHub

    I am interested how this turned out for you. It seems easier to just get a fax server that can use SIP trunks and use a SIP provider that is "Fax Friendly". (supports T.38 well)

    http://www.tmcnet.com/webinar/onetouch/evolving-legacy-2-16-12.html

    Wednesday, April 4, 2012 8:33 PM