polycom video conf jitter problem

[fnbt]

am having a video jitter problem with my video conferencing system. I am new to video conferencing and prioritizing traffic so bear with me here. I am conferencing between 2 sites over a T1 link. The main site has a polycom mp viewstation connected to a 3548 catalyst switch hard coded 10MB half-duplex on the ethernet port, connected to a 7206 router going out over an OC3 split out to a T1 connection to the remote site, that goes into a 2600 series router, into a 3548 catalyst swith hard coded 10/half and out to a polycom viewstation. I experience high collisions/deferred counters on both of the switch ports with the polycom units attached. After some research I have come to the supposition that this is due to a traffic prioritization or queue issue and that I don't have my prioritization set up correctly. I have tried negotiation settings, hubs, and various other ethernet troubleshooting steps to clear my collisions to no avail. I now believe that I just have no idea how to correctly setup queuing for video on my routers. I do have voice already up and working. If anyone has any suggestions or could help me in any way, it would be greatly appreciated.

[al_pruitt]

What type of queuing are you doing? You may have 2 problems here one is the collisions on the switch ports and the second is the queueing set your switches to auto and see if they will sync with the Polycom units I ssume you have swaped the patch cables and moved the Polycom to a different port on the switch. When you get the Polycom's connected to the switche minus the collisions you should look at putting some type of QoS on the WAN link to guarantee bandwidth for Video between sites. Somthing like the config below is easy between just a cople of sites

class-map match-all video

match access-group 102

!

policy-map circpt

class video

priority 480

class class-default

fair-queue 64

access-list 102 permit tcp any any range 3230 3231

access-list 102 permit udp any any range 3230 3235

[juan-santamaria]

You can to verify the aplication of the commands

service-policy out video-police

in your router , because in some aplication with F.R if you don´t apply to the correct dlci definition for a subinterface, the router discard all packet and the polycom present problem of jitter and packet lost.

[chokeah]

We had the same problem with video jitter. We run video over IP. After knocking our heads for two weeks, someone mentioned that they had a similar issue. They suggested that we place capacitors on the Cisco router/switch and BAM. (It cleared up.)

[dthompson]

We are having a the same problem and I may seem confused but what is a capacitor ?