Hi there,
I was doing some testing related to classification encoding on the CMs. I was wondering if there is any way to relate a VLAN tagged packet incoming to the CM with a specific service flow on the upstream. I tried something like this:
...
Upstream Service Flow Encodings
Service Flow Reference:1
Quality of Service Parameter Set:provisioned admitted active
Upstream Maximum Sustained Traffic Rate:512000
Upstream Packet Classification Encoding
Classifier Reference:1
Service Flow Reference:1
IEEE 802.1P/Q Packet Classification Encodings
IEEE 802.1P User_Priority:low 0 high 0
IEEE 802.1Q VLAN_ID:0014
...
It doesn't seem to work. Anyone knows if there is a relation with this line at "show cable modem XXXX verbose":
Optional Filtering Support : {802.1P=N, 802.1Q=N, DUT=Y}
Thanks in advance guys!
your right. The optional filter support showing by the CMTS will let you know the capability of the CM. It's a message by the CM to the CMTS during the registration. There are less CM out there which support Q and P filtering. I used a special Firmware for a Cisco EPC3212 as I've played with BSoD.
Thanks a lot wittman!
So, there is no option? Will I be needing specific firmware to get the VLAN filter up? It doesn't make any sense for me, because the L2VPN capability is actually available, but the VLAN filter doesn't.
Any suggestion?
Hi, yes this is my experience during some tests with BSoD. Only if the P/Q filtering is supported the cable modem will honor the packet classifier for e.g. VLAN. There is also a description in the BSoD spec. Additional to the P/Q Filter capability the cable modem MUST be capable to forward Ethernet frames with a length of 1518 byte (4 byte additional for VLAN) instead of 1514 byte.
Unfortunately BSoD is optional so the default firmware of the cable modem will not support the P/Q filtering.
In your case you have to ask your dealer if he can provide a image with the capability you want.
Best regards,
wittmann
Thanks Wittmann! I'm gonna look for help on my CM's provider!