802.1q COS Auto settings on IP Phones

[ckunkle]

I wanted to setup COS on my Adtran 1224 Layer 2 switch. On the 5621 phones, they are setup for 802.1q=auto by default. But what does that mean? It is on? Is it marking the audio for COS 6?

Does anyone have any insight about the "auto" setting? I don't care about VLANs in this particular situation, more about COS.

TIA

 

[tanderson3733]

The idea of 802.1Q assumes VLANS, meaning the IP Phone is tagging its packets with 802.1Q VLAN tagging. This allows the switch to recognize the Phone's traffic as the voice VLAN, and if there's a PC plugged into the phone that untagged traffic is from the PC and belongs in the Data VLAN. 802.1P is the next step in that, recognizing the tagged packets and prioritizing them over data packets using COS.

The "Auto" setting in the phone lets the phone decide whether it should tag the packets or not.