Method and apparatus for screening request to establish sip session

An apparatus in an internet protocol network for screening a request to establish a SIP session, comprising:

• a received request counter;
• an input module for receiving a first request to establish a SIP session and in operative communication with the received request counter for incrementing the received request counter to maintain a total request count;
• an elevated priority request counter;
• a priority determining module in operative communication with the input module for determining whether the first request includes a resource priority parameter with a first elevated priority value and, if so, in operative communication with the elevated priority request counter for incrementing the elevated priority request counter to maintain a priority request count;
• a priority request comparator module in operative communication with the received request counter and elevated priority request counter for comparing a priority request ratio to a predetermined priority request threshold, wherein the priority request ratio is indicative of a ratio of the priority request count to the total request count;
• and
• a processor module in operative communication with the priority determining module and priority request comparator module for processing each first request that includes the first elevated priority value using more comprehensive screening after the priority request ratio exceeds the predetermined priority request threshold, allowing processing for each first request that includes the first elevated priority value to continue in accordance with the first elevated priority value after the priority request ratio does not exceed the predetermined priority request threshold, and allowing processing for each first request that does not include the first elevated priority value to continue in accordance with a routine priority.

A method for screening a request to establish a SIP session, comprising:

• a) receiving a plurality of requests to establish a SIP session at a network node of an internet protocol network and incrementing a received request counter for each received request to maintain a total request count;
• b) determining whether the each received request includes a resource priority parameter with a first elevated priority value and, if so, incrementing an elevated priority request counter to maintain a priority request count;
• c) comparing a priority request ratio to a predetermined priority request threshold, wherein the priority request ratio is indicative of a ratio of the priority request count to the total request count;
• and
• d) processing each received request that includes the elevated priority value using more comprehensive screening after the priority request ratio exceeds the predetermined priority request threshold, allowing processing for each received request that includes the first elevated priority value to continue in accordance with the first elevated priority value after the priority request ratio does not exceed the predetermined priority request threshold, and allowing processing for each received request that does not include the first elevated priority value to continue in accordance with a routine priority.