Patent ID: 8082580
Filing Date: 2011-12-20
Classification: H04L

Abstract:
1. A method implemented by a network security device that secures a private network from attack by a public network, the method comprising: receiving a session initiation protocol (SIP) message with the network security device from a private server located in the private network, the SIP message requesting a SIP session between a private SIP device in the private network and a public SIP device in the public network; in response to the SIP message, dynamically opening a pinhole within the network security device, the pinhole allowing messages for a plurality of calls for the SIP session to concurrently flow through the network security device between the private and public devices; assigning a set of resources included within a resource pool of the network security device to monitor each call of the plurality of calls occurring over the SIP session, wherein the resource pool stores resources available for use by the network security device; determining whether each of the calls has completed based on a session layer characteristic of a subsequent SIP message associated with each of the calls; and based on the determination, returning the set of resources assigned to monitor each completed call to the resource pool for future use by the network security device.