Path reconstruction and interconnection modeling (PRIM)
Internet data such as Border Gateway Protocol routing information and traceroute measurements are processed to create realistic predictive models of the paths IP traffic is likely to take between any two points on the Internet, even when direct measurements of the paths is not feasible. The prediction includes three categories: topology (what paths may exist), weighting (which paths are more or less likely to be taken under varying operational circumstances), and performance (latency, loss, jitter, etc. across the predicted paths).
1. A method of estimating intra-mode paths, the method comprising the steps of:
receiving in memory at least a partial likely autonomous system (AS)-level path comprising a first AS and a second AS, the at least partial likely AS-level path corresponding to a mode of communication between a first endpoint and a second endpoint;
monitoring and analyzing by a processor border control gateway protocol (BGP) data received from at least one BGP observer;
inferring based on, at least in part, the analyzed BGP data, by the processor, at least one of: (i) a routing policy of the first AS and (ii) a routing policy of the second AS;
selecting by the processor a first hand off pair comprising an exit point from the first AS and an entry point into the second AS, the exit point being in communication with the entry point, the selection being based on, at least in part, at least one of: (i) the inferred routing policy of the first AS, (ii) the inferred routing policy of the second AS, and (iii) a statistical property of traffic associated with at least one of a proxy to the first endpoint and a proxy to the second endpoint, the traffic passing via the first AS; and
identifying by the processor a set of router-level paths within the first AS, from a first entry point into the first AS to the exit point from the first AS within the first hand off pair.
2. The method of claim 1 , wherein the property of the first AS comprises at least one of: (i) a number of router-level hop counts within the first AS on a path from the first entry point into the first AS to the exit point from the first AS within the first hand off pair, (ii) a geographic distance between the first entry point into the first AS and the exit point from the first AS within the first hand off pair, and (iii) a number of points of presence associated with both the first AS and the second AS.
3. The method of claim 1 , wherein the selection step comprises maximizing a first distance within the first AS, the distance comprising at least one of: (i) a number of hop counts on a path to the exit point from the first AS within the first hand off pair, and (ii) a geographic distance between the first entry point into the first AS and the exit point from the first AS within the first hand off pair.
4. The method of claim 3 , further comprising minimizing a second distance from the exit point from the first AS within the first hand off pair to the proxy to the second endpoint, the second distance comprising at least one of: (i) a number of hop counts on a path from the exit point from the first AS within the first hand off pair to the proxy to the second endpoint, and (ii) a geographic distance between the exit point from the first AS within the first hand off pair and the proxy to the second endpoint.
5. The method of claim 1 , wherein the selection of the first hand off pair comprises:
selecting a candidate exit point from the first AS;
selecting a candidate entry point into the second AS such that a frequency of traversal of traffic between the candidate exit point and the candidate entry point is greater than a selected threshold; and
designating: (i) the selected candidate exit point as the exit point within the first hand off pair, and (ii) the selected candidate entry point as the entry point within the first hand off pair.
6. The method of claim 5 , wherein the frequency of traversal of traffic comprises a frequency of traffic directed to at least one of the proxy to the first endpoint and the proxy to the second endpoint.
7. The method of claim 1 , further comprising selecting a router-level path from the identified set of router-level paths such that a path metric corresponding to the selected router-level path satisfies a specified threshold.
8. The method of claim 7 , wherein the path metric comprises at least one of a frequency of traversal of traffic via the selected router-level path, delay, jitter, reliability, and availability.
9. The method of claim 7 , wherein at least one router-level path in the identified set comprises an intermediate router node, and the path metric comprises a frequency of traversal of traffic via an intermediate router node.
10. The method of claim 9 , wherein the frequency of traversal of traffic via the intermediate router node comprises a frequency of traffic directed to at least one of the proxy to the first endpoint and the proxy to the second endpoint.
11. The method of claim 1 , further comprising:
selecting a second hand off pair comprising an exit point from the first AS and an entry point into the second AS, the exit point being in communication with the entry point, the selection being based on, at least in part, at least one of: (i) a property of the first AS, (ii) a property of the second AS, and (iii) a statistical property of traffic associated with at least one of the proxy to the first endpoint and the proxy to the second endpoint, the traffic passing via the first AS; and
identifying a set of router-level paths within the first AS, from a second entry point into the first AS to the exit point from the first AS within the second hand off pair.
12. The method of claim 11 , wherein the second entry point into the first AS is the first entry point into the first AS.
13. A system for estimating intra-mode paths, the system comprising:
a memory; and
a processor configured to:
receive at least a partial likely autonomous system (AS)-level path comprising a first AS and a second AS, the at least partial likely AS-level path corresponding to a mode of communication between a first endpoint and a second endpoint;
monitor and analyze border control gateway protocol (BGP) data received from at least one BGP observer;
infer based on, at least in part, the analyzed BGP data, at least one of: (i) a routing policy of the first AS and (ii) a routing policy of the second AS;
select a first hand off pair comprising an exit point from the first AS and an entry point into the second AS, the exit point being in communication with the entry point, the selection being based on, at least in part, at least one of: (i) the inferred routing policy of the first AS, (ii) the inferred routing policy of the second AS, and (iii) a statistical property of traffic associated with at least one of a proxy to the first endpoint and a proxy to the second endpoint, the traffic passing via the first AS; and
identify a set of router-level paths within the first AS, from a first entry point into the first AS to the exit point from the first AS within the first hand off pair.
14. The system of claim 13 , wherein to select the first hand off pair, the processor is further configured to maximize a first distance within the first AS, the distance comprising at least one of: (i) a number of hop counts on a path to the exit point from the first AS within the first hand off pair, and (ii) a geographic distance between the first entry point into the first AS and the exit point from the first AS within the first hand off pair.
15. The system of claim 14 , wherein the processor is further configured to minimize a second distance from the exit point from the first AS within the first hand off pair to the proxy to the second endpoint, the second distance comprising at least one of: (i) a number of hop counts on a path from the exit point from the first AS within the first hand off pair to the proxy to the second endpoint, and (ii) a geographic distance between the exit point from the first AS within the first hand off pair and the proxy to the second endpoint.
16. The system of claim 13 , wherein to select of the first hand off pair the processor is configured to:
select a candidate exit point from the first AS;
select a candidate entry point into the second AS such that a frequency of traversal of traffic between the candidate exit point and the candidate entry point is greater than a selected threshold; and
designate: (i) the selected candidate exit point as the exit point within the first hand off pair, and (ii) the selected candidate entry point as the entry point within the first hand off pair.
17. The system of claim 13 , wherein the processor is further configured to select a router-level path from the identified set of router-level paths such that a path metric corresponding to the selected router-level path satisfies a specified threshold.
18. The system of claim 13 , wherein the processor is further configured to:
select a second hand off pair comprising an exit point from the first AS and an entry point into the second AS, the exit point being in communication with the entry point, the selection being based on, at least in part, at least one of: (i) the inferred routing policy of the first AS, (ii) the inferred routing policy of the second AS, and (iii) a statistical property of traffic associated with at least one of the proxy to the first endpoint and the proxy to the second endpoint, the traffic passing via the first AS; and
identify a set of router-level paths within the first AS, from a second entry point into the first AS to the exit point from the first AS within the second hand off pair.
19. An article of manufacture, comprising a non-transitory machine-readable medium storing instructions that, when executed by a machine configure the machine, for estimating intra-mode paths, to:
receive at least a partial likely autonomous system (AS)-level path comprising a first AS and a second AS, the at least partial likely AS-level path corresponding to a mode of communication between a first endpoint and a second endpoint;
monitor and analyze border control gateway protocol (BGP) data received from at least one BGP observer;
infer based on, at least in part, the analyzed BGP data, at least one of: (i) a routing policy of the first AS and (ii) a routing policy of the second AS;
select a first hand off pair comprising an exit point from the first AS and an entry point into the second AS, the exit point being in communication with the entry point, the selection being based on, at least in part, at least one of: (i) the inferred routing policy of the first AS, (ii) the inferred routing policy of the second AS, and (iii) a statistical property of traffic associated with at least one of a proxy to the first endpoint and a proxy to the second endpoint, the traffic passing via the first AS; and
identify a set of router-level paths within the first AS, from a first entry point into the first AS to the exit point from the first AS within the first hand off pair.