NEC VoIP phones

I have several NEC DT700 series ITL-8LD-1 VoIP phones and I have the following questions:
- what is the codec used by this model?
- Do I configure my Cisco switch with "mlqs os trust dscp" or "mls qos trust cos" on the interface?

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Norm DickinsonGuruCommented:
There is a series of discussions about this topic on Cisco's website at that may be of assistance. One of the links listed is a youtube video at which may help as well.

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G.711, G.729A, G.722 (Wideband) are all supported on the DT700
leblancAccountingAuthor Commented:
Does the DT700 phone mark the packet as dscp or cos? Thx
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For our two clients with NEC phones they are using DSCP (46)
leblancAccountingAuthor Commented:
For the G.711, G.729A, G.722,  you just configure on the phone. Correct?

Sorry I'm not a voice guy. Thx
Configured on the NEC server.  The phone codec will adapt to the appropriate setting based on the codec enabled for the session by the server.  By default, everything uses G.711 unless changed in system programming.
Ruel TmeizehOwnerCommented:
Which model switch? If it is a 2950 SI, you may need to use mls qos trust cos pass-through dscp, since that model does not handle the rewriting of CoS to DSCP correctly (or I should say in the standard way).
QoS is a fairly complex subject, so some reading on the subject is probably in order :-)

Don't forget that after setting your switch to trust either DSCP markings, CoS tags, or both, you also need to set the queue settings on the switch to process the higher priority frames/packets first. Merely setting the switch to trust the markings doesn't necessarily do anything on it's own; it is the queue settings that allow the actual processing to prefer the marked packets.
leblancAccountingAuthor Commented:
I am using auto QoS. It generates all the queuing for you. Thx
Ruel TmeizehOwnerCommented:
Ok yes if u do the auto commands then it will setup the queues for you.  Good luck with your setup :-D
leblancAccountingAuthor Commented:
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