voip communication problem between site connected over frame relay.

Posted on 2006-03-29
Last Modified: 2012-08-14
hello I have a point-to-point frame-relay environment where sites connect to a 3mbit frame relay pipe on my main site (with a 1751 router) and then this 1751 router connects to a catalyst 4604 router which provides voip functionality.

all sites can call the main site without problems EXCEPT for one of the sites. when this site calls any ip phone on the main site, the remote site can hear the main site talking, but the main site cannot hear the remote site talking.

there are also errors like this on both sites:

SP error stats
*Feb  7 14:31:43.471: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1175, event 6: DSP ID=0x2: DSP error stats
*Feb  7 14:31:52.731: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1220, event 6: DSP ID=0x7: DSP error stats
*Feb  7 14:32:32.671: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1179, event 6: DSP ID=0x1: DSP error stats
*Feb  7 14:32:39.175: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1232, event 6: DSP ID=0x7: DSP error stats
*Feb  7 14:34:39.067: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1200, event 6: DSP ID=0x6: DSP error stats
*Feb  7 14:37:01.795: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1258, event 6: DSP ID=0x8: DSP error stats
*Feb  7 14:37:32.683: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1105, event 6: DSP ID=0x3: DSP error stats
*Feb  7 14:38:12.511: %VTSP-3-DSP_TIMEOUT: DSP timeout on channel 3/0:1:1263, event 6: DSP ID=0x8: DSP error stats
Question by:eggster34
    LVL 36

    Expert Comment

    It could be the RTP voice packets are being blocked from the remote site to the main site. Do you have any filtering or firewalling in place?
    LVL 3

    Accepted Solution

    It is probably related to the first answer, but you can do a show dsp and ensure that the DSP are not being chewed up somewhere else.

    Author Comment

    we changed the codec and fixed it.. thanks alot.

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