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Mapping/tunneling part
BGP keeps routes to major POPs only
1000 – 2000 of these
One prefix per POP
Separate mapping table binds customer prefixes to POPs (ETR address in POP)
Forwarding is two-step:
Map address to ETR
Tunnel packet to ETR address
Not a new idea
Deering’s Map-N-Encap, Kim Claffy et. al.
PPT Version