Set DSCP tagging values in SPA phones

[coryjsanders]

Can someone tell me how to set the DSCP values in a SPA504 or SPA942?  Or are they already set to some default value?  I don't find a way to set them in the phone's GUI.

This Cisco document lists the DSCP values to use:

http://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus1000/sw/4_0/qos/configuration/guide/nexus1000v_qos/qos_6dscp_val.pdf

I want to assign values for the RTP and SIP signaling traffic and use QoS in a router.  46 for the RTP voice traffic and 24 or 26 for SIP signaling (Cisco recommends 24, Polycom seems to recommend 26 for SIP signaling)

Thanks,

Cory

[Dan Lukes]

You can set SIP|RTP TOS/DiffServ value. DSCP is related to DiffServ.

For detailed information read DiffServ -- The Scalable End-to-End QoS Model (start with figure 2 & 3). Ask your LAN administrator for help it you will be still in doubt. He should understand the QoS principles as well as TOS/DiffServ/DSCP relationship.

Note the SPA504G defaults are 0x68 for SIP (e.g. Flash/Minimize delay in TOS world and 26=AF31 in DSCP world) and 0xB8 for RTP (e.g. CRITIC/Minimize_delay+Maximize_troughput in TOS world and 46=EF in DSCP world).

So it seems the phone's configured according your wishes already.