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Feature request: Set CoS (PCP) and DSCP
Posted: Mon Dec 11, 2017 4:52 pm
by mike99
Hi was thinking it was possible to set a PCP value on a VLAN with the QoS feature but seem like not.
It would be great to had the possibility to set the PCP value on a VLAN, maybe on the QoS tab or be able to set a default PCP value for the VLAN in the "by VLAN" config where we set the IP address or enable the IGMP querier.
Since the queue is only local to the switch, setting PCP would be helpfull, it would let devices slower than gigabit, like radios, know which data as the highest priority in a layer 2 network, so what to drop.
Thanks
Re: Set CoS (PCP)
Posted: Fri Mar 30, 2018 10:04 am
by mike99
bump
Re: Set CoS (PCP)
Posted: Fri Mar 30, 2018 10:32 am
by sirhc
Hi Mike99
Eric is on a long Easter weekend, will return Monday, so Bump this on Monday
Re: Set CoS (PCP)
Posted: Mon Apr 02, 2018 11:29 am
by Eric Stern
Our switches only utilized already existing QoS values, it does not set them.
Re: Set CoS (PCP)
Posted: Mon Apr 02, 2018 12:59 pm
by mike99
When adding TCI field, that include the VID, to a header, the switch must also add a priotity value (call 802.1p, CoS or PCP) with 0 value by default.
I would be surprise that it can't be change by a vitesse core. I will look at other switch doc that also use vitesse.
Re: Set CoS (PCP)
Posted: Mon Apr 02, 2018 8:02 pm
by mike99
I looked at this and even lightly managed chipset from the SparX-III familly can do DSCP remarking (layer 3 priority value) and vlan editing (probably mean change 802.1p value).
VSC7427 product brief indicate TCAM based remarking and TCAM based VLAN remarking.
Setting 802.1p value is really basic and the switch should be at leat able to do it while adding TCI field to the paquets, field that include 802.1p value and VID value.
Re: Set CoS (PCP)
Posted: Sat Apr 07, 2018 11:34 am
by mike99
Hi Eric, have you check it back ? Like said, I would be surprise you couldn't at less change the 802.1p value while tagging the vlan. Those the feature need a other licence from microchip that bough microsemi ?
I could understand a licence for DSCP remarking but like said, the switch already write a 802.1p field with 0 value every time it add the VID to a paquet. Those option would be great for ISP and even entreprise that use wireless link, the possibility to tag an other vlan for voice with higher 802.1p value.
Thanks
Re: Set CoS (PCP)
Posted: Mon Apr 09, 2018 9:56 am
by Eric Stern
Oh, the switch core and software are quite able to do it, we just have not implemented the functionality in the UI.
Re: Set CoS (PCP)
Posted: Mon Apr 09, 2018 12:22 pm
by mike99
Could the 802.1p value by VLAN ID be add to the roadmap ?
Thanks
Re: Set CoS (PCP)
Posted: Wed Feb 05, 2020 5:08 pm
by mike99
Bump.
Stephen, be able to set CoS and DSCP would be an awesome added feature for WISP.
Please see section 4.6.3 of following document
http://ww1.microchip.com/downloads/en/D ... 427-02.pdf