FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
[See section 10 and rule 13]
1. TITLE OF THE INVENTION: Method and System for Controlling Qos of Multimedia Session In a Communication Network
APPLICANT:
(a) NAME: Renovau Telecom Pvt Ltd
(b) NATIONALITY: Indian
(c) ADDRESS: #101, Chitrarth Complex,
CG Road, Ahmedabad 380009, Gujarat, India
The following specification particularly describes the invention and the manner in which it is to be performed.
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METHOD AND SYSTEM FOR CONTROLLING QoS OF MULTIMEDIA SESSION IN A COMMUNICATION NETWORK
FIELD OF THE INVENTION
[0001] The present invention generally relates to Quality of Service (QoS) in a communication network. More specifically, the present invention relates to controlling QoS of multimedia session in a communication network.
BACKGROUND OF THE INVENTION
[0002] In the present scenario, a typical approach for delivering multimedia data to terminal equipments over a communication network is by employing a client-server architecture. A terminal equipment can be for example, but is not limited to, a personal computer, a telephone, a cell phone and a Personal Digital Assistant (PDA). In client-server architecture, a multimedia session between one or more terminal equipments is facilitated by a central server. When one or more terminal equipments are involved in a multimedia session, multimedia data such as Audio/Video data may be transmitted from the central server to one or more terminal equipments. Accordingly, when the central server receives requests for multimedia sessions from an increasing number of terminal equipments, the communication network may experience congestion.
[0003] Another approach of delivering multimedia data over the communication network is by employing a peer-to-peer architecture. For example, in a peer-to-peer architecture, one or more terminal equipments involved in a multimedia session communicates the actual multimedia data and quality control packets among the one or more terminal equipments. The quality control packets provide QoS information pertaining to the multimedia session. A central server can control the multimedia session between the one or more terminal equipments through a control signaling protocol. However, since the central server is devoid of the QoS information pertaining to one or more terminal
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equipments, the central server may be unable to control the quality of the multimedia session.
BRIEF DESCRIPTION OF THE FIGURES
[0004] The accompanying figures where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages all in accordance with the present invention.
[0005] FIG. 1 is a block diagram of an environment in which various embodiment of the present invention may function.
[0006] FIG. 2 illustrates a flow diagram of a method for controlling QoS of multimedia session in a communication network in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0007] Before describing in detail embodiments that are in accordance with the present invention, it should be observed that the embodiments reside primarily in combinations of method steps and apparatus components related to method and system for controlling QoS of multimedia session in a communication network. Accordingly, the apparatus components and method steps have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.
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[0008] In this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises ...a" does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.
[0009] It will be appreciated that embodiments of the present invention described herein may be comprised of one or more conventional transaction-clients and unique stored program instructions that control the one or more transaction-clients to implement, in conjunction with certain non-transaction-client circuits, some, most, or all of the functions of a method for controlling QoS of multimedia session in a communication network. The non-transaction-client circuits may include, but are not limited to, a radio receiver, a radio transmitter, signal drivers, clock circuits, power source circuits, and user input devices. As such, these functions may be interpreted as steps of methods for controlling QoS of multimedia session in a communication network. Alternatively, some or all functions could be implemented by a state machine that has no stored program instructions, or in one or more application specific integrated circuits (ASICs), in which each function or some combinations of certain of the functions are implemented as custom logic. Of course, a combination of the two approaches could be used. Thus, methods and means for these functions have been described herein. Further, it is expected that one of ordinary skill, notwithstanding possibly significant effort and many design choices motivated by, for example, available time, current technology, and economic considerations, when guided by the concepts and principles disclosed herein will be readily capable of generating such software instructions and programs and ICs with minimal experimentation.
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[0010] Various embodiments of the present invention provide methods and system for controlling QoS of multimedia session in a communication network. Quality control packets stream and multimedia session control signals are analyzed and one or more actions are performed based on one or more QoS criteria to control the QoS of a multimedia session.
[0011] Referring to the drawings and in particular to FIG. 1, a block diagram of an environment 100 in which various embodiment of the present invention may function is shown. A multimedia server 102 communicates with one or more of a terminal equipment 104-1 and a terminal equipment 104-2 through a communication network 106. For simplicity, the one or more terminal equipment 104-1 and terminal equipment 104-2 will be henceforth referred to as terminal equipments 104-n.
[0012] Multimedia server 102 can be a Voice over Internet Protocol (VoIP) server that can facilitate both interactive and non-interactive multimedia sessions over communication network 106. Further, in an embodiment of the present invention, multimedia server 102 can include a call session control module 108 and a quality management module 110. Communication network 106 can be an Internet Protocol (IP) based broadband communication network that can handle multimedia data. For example, interactive multimedia sessions can be Audio/Video conversations between terminal equipments 104-n. Non-interactive multimedia sessions can be for example streaming of audio or video data from multimedia server 102 to terminal equipments 104-n. Terminal equipments 104-n can be a Personal Computer (PC), a Telephone, a Cell Phone or a Personal Digital Assistant (PDA). Those skilled in the art will recognize that there can be any number of multimedia servers and terminal equipments that can reside in different locations.
[0013] Turning now to FIG. 2, a flow diagram of a method for controlling QoS of a multimedia session in communication network 106 in accordance with an embodiment of the present invention is illustrated. At step 202, quality control packets stream and a multimedia session control signals related to a multimedia session are received at
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multimedia server 102. In an embodiment of the present invention, the quality control packets stream is received at quality management module 110 and the multimedia session control signals are received at call session control module 108. The quality control packets stream provides information regarding QoS of the multimedia session that can serve as control information for multimedia data such as audio/video streams pertaining to the multimedia session. In an embodiment, the multimedia session control signal can be a Session Initiation Protocol (SIP) control signal. The quality control packets stream can be a Real time Transport Protocol (RTCP) stream. Further, the multimedia data can be embedded in a Real Time Protocol (RTP) payload. The quality control packets stream and the multimedia session control signals are received at multimedia server 102 from two different ports pertaining to terminal equipments 104-n.
[0014] In an embodiment, terminal equipments 104-n can be involved in a video session through multimedia server 102. The quality control packets stream for example, the RTCP stream pertaining to audio data of the video session can be received at multimedia server 102 from port 54500 of terminal equipments 104-n. Also, the multimedia data, for example, an RTP payload containing the audio data of the video session may flow through port 54344 between terminal equipments 104-n. Similarly, the quality control packets stream for example, the RTCP stream pertaining to video data of the video session can be received at multimedia server 102 from port 54501 of terminal equipments 104-n. Also, the multimedia data, for example, an RTP payload containing the video data of the video session may flow through port 54346 between terminal equipments 104-n. Hereinafter, quality control packets, multimedia data and multimedia session control signals are referred as RTCP stream, RTP payload and SIP respectively for explaining the working of the invention. However, it would be apparent to a person skilled in the art that any equivalent technologies may be used and are within the scope of the present invention.
[0015] On receiving the RTCP stream and the SIP control signal, the RTCP stream is analyzed by quality management module 110 at step 204, based on one or more QoS criteria. The one or more QoS criteria can be for example, but not limited to, bandwidth
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availability, low packet loss and less network congestion. Subsequently, upon analyzing the RTCP stream, one or more actions are performed at step 206 based on the one or more QoS criteria. The one or more actions can be, for example, but not limited to, sending a request to terminal equipments 104-n to change a codec used for the multimedia session, sending a request to terminal equipments 104-n to decrease the bandwidth and a frame rate used for the multimedia session and changing the current network path used for the multimedia session to another less congested network path using one or more proxy servers.
[0016] In an embodiment, when upon analyzing the RTCP stream, if the available bandwidth for the multimedia session is determined to be less than a bandwidth required by terminal equipments 104-n, steps 202 and 204 are repeated. Alternatively, if the available bandwidth for the multimedia session is determined to be greater than the bandwidth required by terminal equipments 104-n, a request for changing the codec used for the multimedia session is sent from multimedia server 102 to terminal equipments 104-n.
[0017] In another embodiment, upon analyzing the RTCP stream, information regarding actual bandwidth used by terminal equipments 104-n and multimedia data quality information of the multimedia session are obtained at multimedia server 102. The multimedia data can be for example, video data related to the multimedia session. From analyzing the RTCP stream, the packet loss related to the multimedia session may be determined to be less than a predefined packet loss threshold value. In such situations, subsequent RTCP streams received at multimedia server 102 are analyzed by quality management module 110. On the contrary, it can be determined from analyzing the RTCP stream that the packet loss related to the multimedia session is more than the predefined packet loss threshold value. Accordingly, a request is sent to terminal equipments 104-n from multimedia server 102 to decrease the bandwidth and a frame rate of the video data pertaining to the multimedia session.
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[0018] In yet another embodiment, on analyzing the RTCP stream, the actual bandwidth used by terminal equipments 104-n for the multimedia session can be obtained. The packet loss related to the multimedia session due to network path congestion may be determined to be less than the predefined packet loss threshold from analyzing the RTCP stream. In such situations, subsequent RTCP streams received at multimedia server 102 are analyzed by quality management module 110. Alternatively, it may be determined that the packet loss related to the multimedia session due to network path congestion is more than the predefined packet loss threshold. Accordingly, a request can be sent to terminal equipments 104-n to change a current network path to another less congested network path using one or more proxy multimedia servers for facilitating the multimedia session.
[0019] Various embodiments of the present invention provide method and system for controlling QoS of multimedia session in a communication network. Less bandwidth is required for a multimedia server for facilitating a multimedia session between terminal equipments, since the multimedia data pertaining to the multimedia session does not flow through the multimedia server. As a result, the multimedia server can handle an increased number of multimedia sessions that may occur due to an increase in number of terminal equipments. Further, the multimedia server has a better knowledge about the quality of multimedia sessions upon analyzing quality control packets streams that can be influenced by factors such as bandwidth availability, packet loss and network congestion. Moreover, bottlenecks that may arise during multimedia sessions over a communication network can be efficiently controlled by the multimedia server. Accordingly, the multimedia server can control the QoS of multimedia sessions thereby facilitating terminal equipments to have enhanced quality multimedia sessions.
[0020] Those skilled in the art will realize that the above recognized advantages and other advantages described herein are merely exemplary and are not meant to be a complete rendering of all of the advantages of the various embodiments of the present invention.
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[0021] In the foregoing specification, specific embodiments of the present invention have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present invention. The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims. The present invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued.

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METHOD AND SYSTEM FOR CONTROLLING QoS OF MULTIMEDIA SESSION IN A COMMUNICATION NETWORK
ABSTRACT
The present invention provides method and system for controlling QoS of multimedia sessions in a communication network. The method includes receiving a quality control packets stream and a multimedia session control signal pertaining to the multimedia session. Thereafter the method analyzes the quality control packets stream based on one or more QoS criteria and performs at least one action based on the one or more QoS criteria.
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