Upload
alexa-maher
View
229
Download
7
Embed Size (px)
Citation preview
Regional VPLS
Vach Kompella
Joe Regan
Ron Haberman
Alcatel-Lucent
draft-vkompella-l2vpn-rvpls-00 2
Problem: Scaling a VPLS
• Flat architecture• Too many end-to-end sessions• Too much replication• Few labels
draft-vkompella-l2vpn-rvpls-00 3
More on Scaling
• Hierarchical VPLS• Reduces end-to-end sessions• Reduces replication• Too many MACs learned at n-PE• More labels
draft-vkompella-l2vpn-rvpls-00 4
More on Scaling
• Use MS-PWs– Reduces number of sessions– Keeps MAC address learning to minimum– Too much replication– Many more labels
draft-vkompella-l2vpn-rvpls-00 5
What Have We Learned
• Four important dimensions of scaling– Sessions– Replication– MAC address learning– Labels
draft-vkompella-l2vpn-rvpls-00 6
Regional VPLS
• Use MS-PW for scaling sessions
• Use hierarchy to scale replication
• Use hierarchy to reduce labels
• Use regional labels to reduce MAC address learning
draft-vkompella-l2vpn-rvpls-00 7
Regional VPLS Model
Half-FIB
Full-FIB
Regional PE
draft-vkompella-l2vpn-rvpls-00 8
New Concepts
• Regional PE: a dual nature PE which behaves like an S-PE to the core and nPE to the region
• Half-FIB: a FIB of local MAC addresses learned from the region
draft-vkompella-l2vpn-rvpls-00 9
R-VPLS Operation - Forward
Learn M1 at PE1Flood M2
Flood M2
Learn M1 is Blue
Blue Green
Red
PE1
M1
PE2
M2
RPE1RPE2
RPE3Flood M2
draft-vkompella-l2vpn-rvpls-00 10
R-VPLS Operation – Optimized Flooding
Learn M1 at PE1Flood M2
Flood M2 using Flood PW
Learn M1 is Blue
Blue Green
Red
PE1
M1
PE2
M2
RPE1RPE2
RPE3Flood M2
draft-vkompella-l2vpn-rvpls-00 11
R-VPLS Operation - Reverse
Forward M1 to PE1
Learn M2 is Green
Blue
Red
PE1
M1
RPE1RPE2
RPE3
Forward M1on Blue PW
GreenPE2
M2Learn M2 at PE2
draft-vkompella-l2vpn-rvpls-00 12
RVPLS Operation - Unicast
Forward on Green PW
Forward to M2on Green PW
Blue Green
Red
PE1
M1
PE2
M2
RPE1RPE2
RPE3 Forward M2 to PE2
draft-vkompella-l2vpn-rvpls-00 13
Advantages of R-VPLS
• Optimized flooding
• Fewer pseudowires
• Fewer sessions
• Small number of labels
• Limited MAC learning at nPEs
draft-vkompella-l2vpn-rvpls-00 14
Next Steps
• Auto-discovery
• Dual homing of RPEs
• Cascaded regions
• Quantifying the scaling advantages
• Wait for re-charter to ask for consensus as WG draft