OCS 2007 R2 silence at the beginning of incoming calls only RRS feed

  • Question

  • We have Enterprise voice user's who are experiencing silence at the beginning of incoming calls. This is not every call but about 30%. When the users answers the call, they get silence for about 2  - 4 secs at the beginning of the call.

    The users are running the lastest OC 2007 R2 client on the workstation and a catalina phone
    Friday, October 9, 2009 3:14 AM

All replies

  • Sounds like a signaling issue. Are you running any of the servers on VMs??
    Thursday, October 15, 2009 5:55 AM
  • All machine are physical and above specification

    Quad core  3Ghz
    8Gb RAM

    I should clarify that it is only an issue with incoming calls from the PSTN and there are no firewalls or port blocking between the devices.

    Thursday, October 15, 2009 6:54 AM
  • Can you tell us more about your deployment environment?
    1) Are gateway/mediation servers on the same network
    2) Are the users all on the same pool, users distance to pool/gateways?
    3) Are you using any desktop firewall client or virus scanning software?
    4) Does the QoE metrics for the delayed calls show tremendous amount of packet loss or jitter?
    5) Are all the slow calls on a particular frontend (or is this a SE environment)?
    6) Could the windows firewall be turned on on the FE's?
    7) Packet schedule turned off on FE? (needs to be)
    8) Does your environment use IPSec?
    9) Did the problem just start, what changes in environment have been made?
    10) Does it happen consistently to specific users and not others?

    I've had situations were the jitter between MS and Gateway has caused the call answer time to be delayed, additionally IPSec can cause this as well.  I'd see if something like ISA client is running, shut off and see if the problem repros.
    Saturday, October 17, 2009 8:29 PM