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A further use of VID-learning March 2011. Bob Sultan (bsultan@huawei.com). VDP-Learning (currently in Draft). Benefit: A unicast frame received by an EVB Bridge will not be flooded if the frame is destined for a <MAC, VID> ‘registered’ by the adjacent EVB Station. Assoc <A, m>. Assoc <A, m>.
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A further use of VID-learningMarch 2011 Bob Sultan (bsultan@huawei.com)
VDP-Learning (currently in Draft) • Benefit: A unicast frame received by an EVB Bridge will not be flooded if the frame is destined for a <MAC, VID> ‘registered’ by the adjacent EVB Station.
Assoc <A, m> Assoc <A, m> Data <A, m> Data <A, m> Data <A, m> Data <A, m> Data <A, m> Data <A, m> Without VDP Learning Bridge 4 Bridge 5 EVB Station 1 EVB Station 2 EVB Bridge 3 With VDP Learning Bridge 4 Bridge 5 EVB Station 1 EVB Station 2 EVB Bridge 3
A modest benefit • Flooding avoided at an EVB Bridge only for frames destined to <A, m> associated with an adjacent EVB Station; • In general, if the data center contains 100 EVB Bridges, the saving will represent a 1% improvement in flooding;
Assoc <B, n> Assoc <A, m> LLDP EVB TLV NOF = TRUE Data <C, p> Data <C, p> Data <A, m> Data <A, m> Data <C, p> NO FLOOD ZONE A larger benefit is possible Bridge 4 Bridge 5 EVB Station 1 EVB Station 2 EVB Bridge 3 I promise that I will ‘register’ (via VDP Associate) all <MAC, VID> pairs associated with this URP. No flooding when <A, m> has been registered is business as usual for VDP-learning Some <C, p> that is not associated with an EVB Station attached to Bridge 3 <C, p> is unknown, so it is flooded but not flooded on the ‘No Flood’ port to EVB Station 2 as <C, p> cannot be there
The ‘No Flood’ Option • If the EVB Station commits to always register <MAC, VID> pairs on the URP; • then the EVB Bridge will never flood unknown unicast on the corresponding SBP; • if the <MAC, VID> is not found in the FDB of the EVB Bridge, then it cannot lie on the attached EVB Station as it would have been registered;
Update to Draft • Identify NOF bit in existing capabilities field of the EVB TLV; • This is in addition to the existing bit that indicates whether VDP-learning is supported; • [The VDP-learning bit is described in the text, but it appears to be omitted from the figure; should fix;] • FDB contains entry for ‘no more specific MAC or VID’ in which case port map is set to forward on all ports; • when EVB Bridge is informed by EVB TLV that SBP is set to NOF, it sets the corresponding entry of the port-map to ‘filter’; • I can provide text and figures to add to current draft (a small change) if consensus;