11 Contract-switching: A Paradigm Shift… Circuit-switching Packet-switching Contract-switching ISP A ISP C ISP B e2e circuits ISP A ISP C ISP B routable datagrams ISP A ISP C ISP B contracts overlaid on routable datagrams
12 Basic Building Block: Intra- domain Dynamic Contracts Network Core accessed only by contracts Customers Edge Router Edge Router Edge Router Edge Router Edge Router Edge Router Stations of the provider computing and advertising local prices for edge-to- edge contracts.
13 Contract Link capability of managing value flows at a finer granularity than point-to- anywhere deals
16 Path-Vector Contract Routing: Micro-level, On-demand, Reactive User X 2 3 5 ISP A ISP C ISP B 14 [5, A-B, 1-2-4, 15- 20Mb/s, 20-30mins, $4] [5, A, 1-2, 15-30Mb/s, 15-30mins, $8] [5, 10-30Mb/s, 15-45mins, $10] [5, A, 1-3, 5-10Mb/s, 15-20mins, $7] Paths to 5 are found and ISP C sends replies to the user with two specific contract- path-vectors. path request [A-B-C, 1-2-4-5, 20Mb/s, 30mins] [A-C, 1-3-5, 10Mb/s, 15mins] Paths to 5 are found and ISP C sends replies to the user with two specific contract- path-vectors. reply
17 Contract Routing over FCT Model Organization A Organization B ISP C ISP D ISP E Organization C ISP A Contracting at tier-1: long time-scale Contract between two tier-2 networks: medium time-scale Contract between two tier-3 networks: short time-scale ISP B Tier 1 Tier 2 Tier 3