Gu Yingjie (guyingjie@huawei.com)Bob Sultan (bsultan@huawei.com)Li Yizhou (liyizhou@huawei.com)Ben Mack-Crane (tmackcrane@huawei.com)

PCP in VDP Reply

2

Review of Physical Machine

• End-station could send C-tagged traffic or untagged traffic on port; We assume traffic as untagged;

• Tagging performed per Port by Bridge– Priority value maybe tagged by Bridge

Server A

server Bridge

DA, SA, CTAG[PCP=5, CFI=0, VID] T/L, PayloadDA, SA, T/L, Payload

Port X

3

Model in EVB

bridge

VM AVSI x

• VM is aware of VSI as a port;– VM could send C-tagged traffic on port but we assume traffic is

untagged;

• Tagging performed per VSI by ‘tagging entity’ under control of hypervisor;– could be Customer Edge Port of Edge Relay device;– PCP may also be tagged in traffic

DA, SA, T/L, Payload

DA, SA, T/L, PayloadVM BVSI y

server

taggingentity

DA, SA, CTAG[PCP=5, VID] T/L, Payload

DA, SA, CTAG[PCP=3, VID] T/L, Payload

4

Hypervisor knowledge of PCPbridge

VM AVSI x

• Hypervisor might maintain relationship between each VSI and corresponding value of PCP; or

• PCP could be supplied by network, based on information in VSI-type;

• PCP value supplied on VDP rsp;

DA, SA, T/L, Payload

DA, SA, T/L, PayloadVM BVSI y

server

DA, SA, CTAG[5, 96] T/L, Payload

DA, SA, CTAG[3, 114] T/L, Payload

VDP req (VSI x TLV [PCP=null, VID=96])

VDP rsp (VSI x TLV [PCP=5, VID=96])

VDP req (VSI y TLV [PCP=null, VID=114])

VDP rsp (VSI y TLV [PCP=3, VID=114])

hypervisor

5

Proposal

• VDP reserves 2 octets for VID which occupies only 12bits;

• PCP proposal requires no additional field, it could be carried in the rest 4bits in VID field;

6

Proposal

• Communicate 3-bit of PCP value on VDP rsp to aid;– 1-bit PCP Significant (PS) distinguishes PCP = 0 from PCP not specified;– Use high-order bits already reserved in VID field of VDP TLVs;

• If more than one Filter Info Entry then– PCP specified by first (or last) entry with PS = true; or– PCP specified distinctly for each VID with PS = true;

• no preference on this• Applicable to all four currently defined VDP TLV formats (only one

illustrated above);• Current ‘VID’ field of VDP TLV changed to PV (PCP/VID);

– did not want to choose TCI since the information contained is not identical to TCI.

PCP VIDPS

0 1 4bit:

P/V(2 octets)