Abstract: A technique for use in a client, wherein the client supports a state-based signaling protocol (e.g., Session Initiation Protocol or SIP), includes initiating a given session state between the client and a server that also supports the state-based signaling protocol, and refreshing the given session state in a randomized manner. Further, a technique for use in a server, wherein the server supports a state-based signaling protocol (again, e.g., SIP), includes randomly assigning an expiration time duration for a given session state between the server and a client that also supports the state-based signaling protocol, and reporting the randomly assigned expiration time for the given session state to the client. By randomizing various behaviors of the client, the server, or both, bursty traffic in the communication network is reduced or eliminated.

Abstract: The number of CPU cycles required to reclaim object memory space in a memory management process is reduced by using a two phase approach. A data structure exists for each object that is to be loaded into object memory space. One part of the data structure is the object definition. The other part is a MM (Memory Management) immunity annotation or value that controls the frequency with which the object must actually be examined to determine if it is suitable for reclamation. On each iteration of the memory management process, the object's MM immunity value is tested to determine whether it is greater than a predetermined threshold. If greater than the threshold, the value is decremented, but the object is not actually examined for its suitability for removal. If the value equals the threshold, the object itself is examined.

Abstract: A technique for use in a client, wherein the client supports a state-based signaling protocol (e.g., Session Initiation Protocol or SIP), includes initiating a given session state between the client and a server that also supports the state-based signaling protocol, and refreshing the given session state in a randomized manner. Further, a technique for use in a server, wherein the server supports a state-based signaling protocol (again, e.g., SIP), includes randomly assigning an expiration time duration for a given session state between the server and a client that also supports the state-based signaling protocol, and reporting the randomly assigned expiration time for the given session state to the client. By randomizing various behaviors of the client, the server, or both, bursty traffic in the communication network is reduced or eliminated.

Abstract: A method, system and computer program product for limiting extreme loads and reducing fluctuations in load at session servers. An admission rate controller of a SIP router calculates the “deflator ratio” equal to the average number of in-dialog messages received over a first fixed interval of time divided by the average number of out-of-dialog messages received over a second fixed interval of time. Further, the admission rate controller calculates the “dampening ratio” equal to the maximum number of messages allowed over a period of time divided by the number of messages admitted over a previous time interval. When an overload condition has been detected, the admission rate controller calculates the maximum number of out-of-dialog messages to be sent to its associated SIP server based on the deflator and dampening ratios. In this manner, a smoother transition from the overload condition to the non-overload condition may occur.

Abstract: A technique for use in a client, wherein the client supports a state-based signaling protocol (e.g., Session Initiation Protocol or SIP), includes initiating a given session state between the client and a server that also supports the state-based signaling protocol, and refreshing the given session state in a randomized manner. Further, a technique for use in a server, wherein the server supports a state-based signaling protocol (again, e.g., SIP), includes randomly assigning an expiration time duration for a given session state between the server and a client that also supports the state-based signaling protocol, and reporting the randomly assigned expiration time for the given session state to the client. By randomizing various behaviors of the client, the server, or both, bursty traffic in the communication network is reduced or eliminated.

Abstract: A method, system and computer program product for managing bursts of traffic. A counter, referred to herein as a “frequency counter,” is incremented during those time intervals an overload condition is detected and is decremented during those time intervals an overload condition is not detected. An overload condition may refer to when the number of out-of-dialog messages exceeds a threshold value corresponding to the maximum number of out-of-dialog messages that should be accepted and forwarded to an associated session server. If the count of the frequency counter exceeds some pre-configured value, then traffic that exceeds the threshold for the overload condition is stopped from being sent to the associated session server. Otherwise, traffic that exceeds the threshold for the overload condition is permitted to be sent to the associated session server. By managing bursts of traffic in such a manner, the effective utilization of session servers is improved.

Abstract: A technique for use in a client, wherein the client supports a state-based signaling protocol (e.g., Session Initiation Protocol or SIP), includes initiating a given session state between the client and a server that also supports the state-based signaling protocol, and refreshing the given session state in a randomized manner. Further, a technique for use in a server, wherein the server supports a state-based signaling protocol (again, e.g., SIP), includes randomly assigning an expiration time duration for a given session state between the server and a client that also supports the state-based signaling protocol, and reporting the randomly assigned expiration time for the given session state to the client. By randomizing various behaviors of the client, the server, or both, bursty traffic in the communication network is reduced or eliminated.

Abstract: A method, system and computer program product for managing bursts of traffic. A counter, referred to herein as a “frequency counter,” is incremented during those time intervals an overload condition is detected and is decremented during those time intervals an overload condition is not detected. An overload condition may refer to when the number of out-of-dialog messages exceeds a threshold value corresponding to the maximum number of out-of-dialog messages that should be accepted and forwarded to an associated session server. If the count of the frequency counter exceeds some pre-configured value, then traffic that exceeds the threshold for the overload condition is stopped from being sent to the associated session server. Otherwise, traffic that exceeds the threshold for the overload condition is permitted to be sent to the associated session server. By managing bursts of traffic in such a manner, the effective utilization of session servers is improved.

Abstract: A method, system and computer program product for limiting extreme loads and reducing fluctuations in load at session servers. An admission rate controller of a SIP router calculates the “deflator ratio” equal to the average number of in-dialog messages received over a first fixed interval of time divided by the average number of out-of-dialog messages received over a second fixed interval of time. Further, the admission rate controller calculates the “dampening ratio” equal to the maximum number of messages allowed over a period of time divided by the number of messages admitted over a previous time interval. When an overload condition has been detected, the admission rate controller calculates the maximum number of out-of-dialog messages to be sent to its associated SIP server based on the deflator and dampening ratios. In this manner, a smoother transition from the overload condition to the non-overload condition may occur.

Abstract: The number of CPU cycles required to reclaim object memory space in a memory management process is reduced by using a two phase approach. A data structure exists for each object that is to be loaded into object memory space. One part of the data structure is the object definition. The other part is a MM (Memory Management) immunity annotation or value that controls the frequency with which the object must actually be examined to determine if it is suitable for reclamation. On each iteration of the memory management process, the object's MM immunity value is tested to determine whether it is greater than a predetermined threshold. If greater than the threshold, the value is decremented, but the object is not actually examined for its suitability for removal. If the value equals the threshold, the object itself is examined.