Patent ID: 7620037

Claim:
An adaptive MULTIHOMING SYSTEM for reliable monitoring and reporting UP/DOWN status of a plurality N of ISP-ACCESS CLOUDs connected to said adaptive MULTIHOMING SYSTEM, comprising; a) an ACCESS CLOUD STATE DETECTION apparatus comprising: i) a permanent memory store PM- 1 ; ii) a dynamic memory store DM- 1 ; iii) a computing resource CR- 1 ; comprising: (1) a CPU-& I/O chip set; (2) a Control Program and a plurality of Program_Modules in cooperation with said CPU-& I/O chip set that control the ACCESS CLOUD STATE DETECTION to execute operations, comprising; (a) for each one of said N ISP-A/C's, A continually and continuously read packet data flow information for packets directed to and from each one of said N ISP-A/C's; (b) on a first condition for a packet directed to and from each ISP-A/C-n of said N ISP-A/C's, store said directed packet's flow information in a TCP-Flow-Table; (c) on a second condition for a packet directed to each ISP-ACCESS CLOUD-n of said N ISP-ACCESS CLOUDs, add TCP destination IP address of said packet to, and delete an old TCP destination IP address from, a list of TCP destination IP addresses allocated to a memory portion DYNAMIC SEED LIST in said dynamic memory; (d) on a third condition for packets directed to an ISP-ACCESS CLOUD-n of said N ISP-ACCESS CLOUDs, update a permanent memory portion DEFAULT SEED LIST in said memory store PM- 1 with said list of TCP destination IP addresses stored in Dynamic Memory- 1 ; (e) for each inbound packet from each ISP-ACCESS CLOUD-n of said N ISP-ACCESS CLOUDs, determine the inbound byte count, and add said count to a corresponding ISP-ACCESS CLOUD-n inbound-byte-counter, and on a regular, periodic interval of integer k-seconds, compare its inbound-byte-counter value at time=t, [ISP-n (t)] with its inbound-byte-counter value at time=t+k, [ISP-n (t+k)], and if said values are the same, set a Blackout_Hint variable to YES, and initiate an UP/DOWN status test of said ISP-ACCESS CLOUD-n to determine if said ISP-ACCESS CLOUD-n is UP or DOWN; (f) on a fourth condition for packets directed to a TCP destination IP address, send a set PROBE of packet sequences, to said TCP destination IP address through each one of said N ISP-ACCESS CLOUDs, measure a Round Trip Time value to and from said TCP destination IP address for each one of said N ISP-ACCESS CLOUDs, and store said value for each one of said N ISP-ACCESS CLOUDs and each said destination address in a ROUND TRIP TIME table.