Hello Jeff,
The SPA500 phones do tagging for ToS/DiffServ:
Default QoS for SPCP Mode
If there is no network policy from CDP or LLDP-MED, the default network policy is
used. CoS is based on a pre-defined value of5. It is applicable only if the manual
VLAN is enabled and manual VLAN ID is not equal to 0, 1, or 4095. ToS is based on
precedence value from the StartMediaTransmission Message from the Unified
Communications 500 Series for the Cisco SPA525G/525G2. However, ToS is
based on the value specified for the specific extension in the web administration
interface for the Cisco SPA50X IP phone.
Source SPA500 admin guide p.148:
http://www.cisco.com/en/US/docs/voice_ip_comm/csbpipp/ip_phones/administration/guide/spa500_admin.pdf
HTH,
Alex
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