1. P4P Implementation Yale LANS

2. P4P Portal Services Location Portal Service pDistance Portal Service Two services because  Different functionalities  Different update time-scales location large but more stable

3. Location Portal Service Allows an ISP to aggregate the Internet address space to define its own “my- Internet” view  Highly preferred by ISPs during our field tests The “my-Internet” view of an ISP consists of a set of PIDs (partition IDs)

4. PID A PID denotes a set of network locations  A generalization of network aggregation concepts such as autonomous system (AS) or intradomain routing area  Can denote aggregation such as a subnet, a point of presence (PoP), a type of customers (dsl vs fiber), an AS, or a set of ASes  May define hierarchical PIDs, but focus on one level so far

5. “My-Internet” View of isp1: an Example pid1.intra.isp1 pid2.intra.isp1 pid3.intra.isp1 pid4.intra.isp1 pid5.exter.isp1pid6.exter.isp1pid7.exter.isp1

6. Implementation: Interfaces Defined in the Location Portal Service GetPID (MUST)  IP address → PID  A list of IP addresses → their corresponding PIDs GetPIDMap (SHOULD)  PID → list of IP prefixes/ASNs belonging to the PID  A list of PIDs → their corresponding PID Maps  Null → PID Maps for all PIDs

7. pDistance Portal Service The pDistance Portal Service allows an ISP to define the pDistance for any given pair of network locations  network location: IP address/PID If input is a pair of IP addresses, the ISP may either return more precise metric, or internally map IP addresses to PIDs and then return metric  pDistance: path metric distance, provider distance

8. pDistance Semantics of pDistance depends on  Ordinal or numerical (default) pDistance  Type of pDistance, e.g., Routing Hop-Count pDistance Routing Air-Mile pDistance Routing Cost pDistance (default if not indicated)

9. Example: Routing Cost pDistance of isp1 pid1 pid2 pid3 pid4 pid5 pid6 pid7 OSPF path cost; TE dual variables f(BGP local pref., AS_PATH, …) Multihoming cost opt. dual

10. Implementation: Interface Defined in the pDistance Portal Service GetpDistance (MUST)  [a pair of network locations, and optionally type of pDistance] → pDistance value  [A set of pairs of network locations and optionally type of pDistance] → pDistance values

11. How May a P2P Application Use these P4P Portal Services? This depends on the applications It is a place for application innovation

12. Example: Tracker-Based The tracker resolves the PIDs of clients  By using PID Maps The tracker uses a peering weight matrix to select initial peers for a new client Peering weight matrix computed according to channel state and pDistance matrix

13. Tracker ISP Data Structures ISP 1ISP M ISPPIDMap PIDMap PIDMapPortalAPI ISPPDistanceMap PDistanceMap PDistanceMapPortalAPI

14. Per Channel Data Structures A list of ISPs maintained for the channel An ISPView for each maintained ISP  An ISP view partitions the peers in the channel according into peer groups  A PeeringGuidance matrix guides how to select peers from the peer groups, e.g., for a peer in peer group 1, how many peers to select from group 1, from group 2, …

15. Per Channel Data Structures isp1ispK Peer Group1 Peer Group2 Peer Group 3 Peer Group 4

16. Per Channel Data Structures: Peer Group by PID pid1 pid7 list of clients in pid1 list of clients in pid7 total intra ISP pid 1 pid 2 pid 3 pid 4 pid 5 pid 6 pid 7 pid1 pid2 pid3 pid4 peering weight matrix