Patent ID: 8301744
Filing Date: 2012-10-30
Classification: H04L

Abstract:
1. A system executed by a computer for transparently assuring quality of service (QoS) for Session Initiation Protocol (SIP) users and applications in a SIP session between a source user network and a destination user network communicating via a Differentiated Services (DiffServ) core network, each user network having a source and destination SIP user agent respectively, the system comprising: a Bandwidth Manager to provision pipes in the core network between source user networks and destination user networks, wherein each pipe is configured to transport a plurality of traffic flows of a plurality of DiffServ classes that are communicated via SIP sessions between a source user network and a destination user network; a QoS Agent for accepting and/or rejecting a SIP session by checking for availability of bandwidth in the pipe for each incoming traffic flow of the SIP session first for the default DiffServ class for the traffic flow and if that bandwidth is not available then checking for bandwidth availability for the degraded class for the traffic flow as specified by the Session QoS Degradation policy, admitting the flow only if bandwidth is available either for its default DiffServ class or for its degraded DiffServ class, and reconfiguring the marking policies for an admitted flow in the ingress Session Border Controller if the flow is admitted in its degraded DiffServ class; where the QoS Agent determines the session bandwidth requirement from a header in an incoming SIP Invite message, increases or decreases the bandwidth of the pipe based on a plurality of predetermined policies on high and low thresholds on pipe bandwidth allocated to SIP sessions, pipe bandwidth increments and pipe bandwidth decrements; a Session Border Controller between each user network and the core network to police an incoming packet and mark said incoming packet with Differentiated Services (DiffServ) code points based on policies configured by the QoS Agent; and a SIP proxy server between the source SIP user agent and destination SIP user agent, wherein the SIP proxy server is configured to forward all incoming SIP requests to the QoS Agent.