Patent Publication Number: US-8971185-B1

Title: Tiered subscriber service with advanced header compression methods in a VOIP system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/126,090, filed May 23, 2008, entitled “Tiered Subscriber Service With Advanced Header Compression Methods In A VOIP System.” 
    
    
     SUMMARY 
     The present invention is defined by the claims below. Embodiments of the present invention provide a system and method for providing a dynamic tiered subscriber service in a mobile telephone network using a voice over IP “VOIP” system (e.g. 3/4G system). A dynamic, tiered-subscriber service allows the bandwidth allotted to users subscribing to different levels of service to be adjusted between communication sessions to accommodate changing network conditions. Embodiments of the present invention have several practical applications in the technical arts including allowing header compression and a dynamic tiered subscriber functionality to operate concurrently while providing VOIP wireless communications. 
     In a first illustrative aspect, one or more computer-readable media with computer-executable instructions embodied thereon that when executed performs a method of setting up a wireless telephone call utilizing VOIP technology with dynamically adjustable bandwidth allocation based on tiered subscriber service is provided. The method includes, during setup of the wireless telephone call including a mobile-communication device as at least one endpoint of the wireless telephone call, installing, on a gateway, a header compression policy governing a flow of voice packets between the mobile-communication device and a radio access network. The header compression policy including a first attribute-value pair that defines header compression parameters for the voice packets and a second attribute-value pair that instructs the gateway to allocate bandwidth for the wireless telephone call according to a subscriber service level associated with the mobile-communication device. 
     In another illustrative aspect, a communication system for enabling a wireless VOIP phone call that utilizes header compression of voice packets and allocates bandwidth for the phone call based on a subscriber service level associated with a mobile-communication device that is an endpoint for the phone call is provided. The system including a radio access network for transmitting data between the mobile-communication device and a gateway, wherein the radio access network is communicatively coupled to the gateway. The gateway establishes a data flow between the radio access network and another end point of the phone call. The system also includes a policy implementation component for pushing a header compression policy to the gateway that is communicatively coupled to the gateway, wherein the header compression policy instructs the gateway to compress a voice packet header, and allocate bandwidth to the phone call based on a subscriber class associated with the mobile-communication device. 
     In a final illustrative aspect, one or more computer-readable media with computer-executable instructions embodied thereon that when executed performs a method of setting up a wireless telephone call utilizing VOIP technology with dynamically adjustable bandwidth allocation based on tiered subscriber service is provided. The method includes establishing a main connection between a mobile-communication device and a gateway. The method also includes installing a static policy on the gateway that governs signaling during set up of the wireless telephone call. The method further includes establishing a signaling connection between the mobile-communication device and a call flow component that establishes a communication session. The method also includes installing a signaling policy on the gateway that provides a traffic-flow-template for VOIP signaling traffic. The method also includes establishing a media connection between the mobile-communication device and a different communication device participating in the wireless telephone call, wherein the media connection carries voice traffic as voice packets. The method further includes installing a bearer policy on the gateway that provides a traffic-flow-template for the voice traffic. The bearer policy specifies a bandwidth allocation based on a subscriber class associated with the mobile-communication device. The bearer policy also instructs the gateway to perform header compression on the voice packets. The system further includes installing a header compression policy on the gateway that assigns bandwidth based on the subscriber class associated with the mobile-communication device, and marks flow of the voice packets for header compression, thereby completing a setup of the wireless telephone call. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Illustrative embodiments of the present invention are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein: 
         FIG. 1  depicts an illustrative wireless networking environment suitable for practicing an embodiment of the present invention; 
         FIG. 2  depicts a call flow setup in accordance with an embodiment of the present invention; 
         FIGS. 3-6  depict illustrative call policies loaded on a gateway during the call set up, in accordance with embodiments of the present invention; 
         FIG. 7  is a flow chart that depicts a method of setting up a wireless telephone call utilizing VOIP technology with dynamically adjustable bandwidth allocation based on tiered subscriber service, in accordance with an embodiment of the present invention. 
         FIG. 8  is a flow diagram that depicts a method of setting up a wireless telephone call utilizing VOIP technology with dynamically adjustable bandwidth allocation based on tiered subscriber service, in accordance with embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Throughout the description of the present invention, several acronyms and shorthand notations are used to aid the understanding of certain concepts pertaining to the associated system and services. These acronyms and shorthand notations are solely intended for the purpose of providing an easy methodology of communicating the ideas expressed herein and are in no way meant to limit the scope of the present invention. The following is a list of these acronyms:
         3G Third Generation Communications System   4G Fourth-Generation Communications System   802.11 Wireless Local Area Network Standards   AAA Authentication, Authorization, and Accounting   ASN Access Service Network   ASN-GW Access Service Network Gateway   CDMA Code Division Multiple Access   CD-ROM Compact Disc Read-Only Memory   CoS Class of Service   DVD Digital Versatile Disc   EEPROM Electrically Erasable Programmable Read-Only Memory   GPRS General Packet Radio Service   GSM Global System for Mobile Communications   HA Home Agent   IMS IP Multimedia Subsystem   IP Internet Protocol   PC Personal Computer   PDA Portable Digital Assistant   PDSN Packet Data Serving Node   QoS Quality of Service   RAM Random Access Memory   ROM Read-Only Memory   TDMA Time Division Multiple Access   VOIP Voice over Internet Protocol   WIMAX Worldwide Interoperability for Microwave Access       

     Further, various technical terms are used throughout this description. A definition of such terms can be found in Newton&#39;s Telecom Dictionary by H. Newton, 21 st  Edition (2005). These definitions are intended to provide a clearer understanding of the ideas disclosed herein but are not intended to limit the scope of the present invention. The definitions and terms should be interpreted broadly and liberally to the extent allowed the meaning of the words offered in the above-cited reference. 
     Embodiments of the present invention may be embodied as, among other things: a method, system, or computer-program product. Accordingly, the embodiments may take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware. In one embodiment, the present invention takes the form of a computer-program product that includes computer-useable instructions embodied on one or more computer-readable media. 
     Computer-storage media include both volatile and nonvolatile media, removable and non-removable media, and contemplates media readable by a database, a switch, and various other network devices. Network switches, routers, and related components are conventional in nature, as are means of communicating with the same. Computer-storage media, or machine-readable media, include media implemented in any method or technology for storing information. Examples of stored information include computer-useable instructions, data structures, program modules, and other data representations. Computer-storage media include, but are not limited to RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile discs (DVD), holographic media or other optical disc storage, magnetic cassettes, magnetic tape, magnetic disk storage, and other magnetic storage devices. These memory components can store data momentarily, temporarily, or permanently. 
     Embodiments of the present invention, allow phone calls involving a mobile telephone to be to be conducted using VOIP technology with header compression of the voice packets and dynamically adjustable tiered subscriber service. As described previously, a dynamic, tiered-subscriber service allows the bandwidth allotted to users subscribing to different levels of service to be adjusted between sessions to accommodate changing network conditions. This is in contrast to a static tiered subscriber service, which allocates a designated bandwidth based on subscriber tier without regard for network conditions (e.g. present bandwidth usage in the network). Header compression involves compressing the voice packet header to a reduced number of bites. For the purpose of this application, a voice packet is a data packet containing audio content of a telephone call. Generally, a voice packet includes a header that helps direct the transport of the voice packet and a payload that contains the audio content data. The header may include a RTP header, an UDP header, and an IP header all of which can be compressed into a reduced number of bits. Compressing the header can save significant amounts of bandwidth. In one embodiment, Robust Header Compression (ROHC) is used as the compression standard. Other header compression methods, such as IPHR and LLA-HR (Link-layer assisted header removal) may be used. Previously, it has not been possible to utilize header compression and dynamically tiered-subscriber service with VOIP technology. 
     Embodiments of the present invention enable simultaneous header compression and dynamic tiered-subscriber service through a new call flow set up that includes a new policy. The new policy is given preference over the other installed policies and includes new attribute value pairs that enables both header compression and dynamic bandwidth adjustments. 
     Exemplary Networking Environment 
     Referring to the drawings generally, and initially to  FIG. 1  in particular, an exemplary wireless-networking environment suitable for use in implementing embodiments of the present invention is illustrated and designated generally as reference numeral  100 . Wireless-networking environment  100  is but one example of a suitable wireless-networking environment and is not intended to suggest any limitation as to the scope of use or functionality of the invention. Neither should wireless-networking environment  100  be interpreted as having any dependency or requirement relating to any one or combination of components illustrated. In particular, some terms used to describe components of wireless network  100  are commonly associated with networks utilizing CDMA Rev A protocols, but the invention is not meant to be limited to networks employing CDMA Rev A protocols. In the case where a CDMA Rev A specific term is used, it should be understood that embodiments of the present invention may work equally well utilizing functionally equivalent components in networks employing other protocols, such as, for instance, the next generations of global system for mobile communications (“GSM”), or the next generations of time division multiple access (“TDMA”) protocols. 
     In wireless-networking environment  100 , the mobile-communication device  102  is a wireless terminal that is adapted to receive communications over a wireless network. The mobile-communication device  102  may include a bus (not shown) that directly or indirectly couples the following devices: memory (not shown), one or more processors (not shown), one or more presentation components (not shown), input/output (I/O) ports (not shown), I/O components (not shown), and a power supply such as a battery. The mobile-communication device  102  may use next generation standard air interface protocols, such as code division multiple access Rev A, HSDPA, or WiMax as well as others, to communicate with the radio access network  108 . Other network communication interface arrangements are also possible. 
     The wireless-communication device  102  may take any of a variety of forms. By way of example, the mobile-communication device  102  may be a mobile telephone, a computer, a personal digital assistant (“PDA”) or any combination of these or other devices. The mobile-communication device  102  may be configured to receive and/or convey information such as voice and data (e.g., fax, e-mail and other text messages) and/or other media (e.g., audio, video and graphics). Further, the mobile-communication device  102  may include input and output facilities such as a touch-pad, a keyboard, a camera, a display, a microphone and/or a speaker. The mobile-communication device  102  may be equipped with web browsing software to allow subscribers to communicate with web servers over an Internet Protocol (IP) network (i.e., the Internet). The mobile-communication device  102  may be configured to receive, by way of example and not limitation, telephone calls, emails, text messages, pages, pictures, video, TV shows, radio, music, calendar reminders, and other files with communicative properties. For the sake of illustration, throughout this disclosure the mobile-communication device  102  is the device with which embodiments of the present invention are practiced. 
     Communications device  106  is capable of placing voice calls using the IMS  118  core, including Quality of Service (QoS) technologies. Communications device  106  could be a wireless or landline communications device. 
     The radio access network  108  communicates over a wireless air interface utilizing a wireless access network, such as 3G, 4G, CDMA, GPRS, GSM, TDMA, WIMAX, and the like. In one embodiment, the wireless access network might be a mobile wireless broadband access network. In embodiments, radio access network  108  provides gateway header data to packets such that packets received by radio access network  108  may be communicated to gateway  112 . As used herein, a packet refers to a formatted block of data. A packet can include any data, such as, for example, text, numerals, symbols, characters, audio (e.g., voice), video, images, and the like. Only one radio access network is shown, and without its many components, for the sake of clarity. 
     The radio access network  108  communicates with an access gateway  112 . Access gateway  112  provides a boundary between radio communication functions embodied in one or more radio access systems that form the access-facing portion of wireless-networking environment  100  and the standard internet protocol (IP) communication functions (including Mobile IP) embodied in the public-network facing portion (e.g., network  122 ) of wireless-networking environment  100 . In one embodiment, access gateway  112  performs protocol conversion. That is, access gateway  112  may convert signals from a first protocol to a second protocol. Access gateway  112  might be, for example, an ASN-GW, a PDSN, a SGSN/GGSN, and the like. In embodiments, access gateway  112  can be coupled with a foreign agent (FA). In one embodiment, access gateway  112  provides home agent (HA) header data to packets such that packets received by access gateway  112  may be communicated to a HA. Packets might be tunneled to and from an HA over unencrypted IP-in-IP tunneling. 
     Wireless-networking environment  100  includes a communication network  122 . The communication network  122  may include one or more mobile networks, one or more packet based networks, including the Internet, and the public switched telephone network (PSTN). The various components within the communication network  122  may be owned, and/or operated by, multiple entities, commercial or otherwise. The communication network  122  is configured to transmit a variety of communication formats. The communication network  122  is adapted to carry these communication formats between a variety of communication devices including, phones, computers, mobile phones, PDA&#39;s, pagers, server computers, client computers, and fax machines. The lists of communication devices and communication formats is not exhaustive and other devices and communication formats could be compatible with, or carried on, the communication network  122  and be compatible with embodiments of the present invention. 
     As stated, the communication network  122  may include one or more wireless networks that may be operated by one or more wireless service providers. The wireless network allows mobile-communication device  102  to communicate with other mobile-communication devices and with other communication devices connected to the communication network  122 , such as communication device  106 . 
     Policy changing resource function (PCRF)  124  is a device that is used to authorize various bandwidth allocations for flows to a mobile device, such as mobile-communication device  102 . A flow is a communication link established by a mobile device for transmitting and receiving data packets between the same two endpoints. In an embodiment, the flow can include common characteristics such as a destination IP address, a port range, and a type of protocol being used (User Datagram Protocol (UDP) or Transmission Control Protocol (TCP) for example). Some examples of different types of flows are a signaling flow, a bearer flow, and a best effort flow. In an embodiment, the PCRF  124  is utilized to pre-authorize a flow before data traffic is transmitted on the flow. PCRF  124  may also be used to upgrade or downgrade a flow that has been authorized. In an embodiment, upgrading a flow can include increasing the bandwidth allocation of the flow, while downgrading a flow can include decreasing the bandwidth allocation of the flow or terminating the flow. 
     Call service control function (CSCF)  126  is a device that is configured to receive session initiation protocol (SIP) signals from a mobile device that relate to a mobile device establishing or terminating a communication session with one or more other devices. In an embodiment, the CSCF  126  is part of an IP multimedia subsystem (IMS)  118 . The CSCF receives a SIP invite message from the mobile device to establish a communication session. The CSCF  126  then generates an authorization request message (AAR) to send to the PCRF  124  so the PCRF  124  can authorize the flow. 
       FIG. 2  is a ping-pong diagram of an exemplary method  200  of call flow creation used to create a flow that allows both header compression and dynamically adjusted levels of service, according to an embodiment of the invention.  FIG. 2  shows communications that occur between components to set up a wireless telephone call between mobile-communication device  102  and communication device  106  that uses Voice over Internet Protocol (VOIP). The intermediary components include radio access network  108 , gateway  112 , PCRF  124 , CSCF  126 , and communication device  106 . These components have been described previously with reference to  FIG. 1 . 
     The primary purpose of  FIG. 2  is to illustrate the sequence in which policies  260 ,  262 ,  264 ,  266  are installed on the gateway  112  during a call set up, in accordance with an embodiment of the present invention. The actual policies will be described in detail with reference to  FIGS. 3-6 . Initially, the main A10 connection  224  is established between the mobile-communications device  102  and the gateway  112  using best effort traffic. The static policy  260  may be installed on the gateway  112  at this time. In one embodiment, the static policy  260  is present on the gateway  112  at the time the A10 connection  224  is established. The gateway  112  chooses the static policy to install based on the type of A10 connection  224  that is established. 
     Next, the SIP signaling connection  226  is established between the wireless-communication device  102  and the CSCF  126 . The SIP signaling connection  226  carries the call set up traffic. At this time, the signaling traffic-flow-template policy  262  is installed on the gateway. In one embodiment, the signaling traffic-flow-template policy  262  is pushed from the PCRF  124  to the gateway  112  as part of the credit control request (CCR) message  242 . In response to the CCR message  242 , the gateway  112  may transmit a credit control answer (CCA) message  244  to the PCRF  124 . 
     Next, the media connection  228  between the mobile-communication device  102  and the communication device  106  is established. The media connection carries the voice traffic once the call is set up. In conjunction with the media connection, the bearer traffic-flow-template policy  264  is installed. In one embodiment, the bearer traffic-flow-template policy  264  is pushed from the PCRF  124  to the gateway  112  as part of the CCR message. Finally, the header compression policy  266  is installed. In one embodiment, the header compression policy is pushed from the PCRF  124  to the gateway  112  as part of the re-authorization request (RAR) message  230 . In response to the RAR message, the gateway sends a re-authorization answer RAA message to the PCRF  124 . 
     After the bye message  234 , the various connections are torn down in reverse order and the policies are uninstalled. First, the header compression policy  266  is uninstalled. Next, the media connection is torn down  236  and the bearer traffic-flow-template policy  264  is uninstalled. Next, user IMS deregistration occurs and the signaling traffic-flow-template policy  262  is uninstalled. Finally, the A10 connection is torn down  240  and the static policy  260  is uninstalled. At this point, the communication session used to complete the call is over. 
     Turing now to  FIGS. 3-6 , characteristics of polices  260 ,  262 ,  264 , and  266  are shown, in accordance with embodiments of the present invention. The policy attributes shown on the policies are not meant to be comprehensive. Depending on the implementation details, other policies attributes may be included in the policy. The policy descriptions in  FIGS. 3-6  use language consistent with the Rev A standard and the Diameter communications protocol. It is important to note that embodiments of the present invention could be implemented within other standards and protocols and is not intended to be limited to the Rev A standard and the Diameter communications protocol. The gateway  112  handles data packets associated with the call based on the content of policies described in  FIGS. 3-6 . 
       FIG. 3  shows characteristics of static policy  260 . Static policy  260  governs the signaling flow during the call set-up. As described previously, the static policy may be installed on the gateway  112  at the time the initial A10 connection  224  is set up. Static policy  260  consists of two sub-policies; VOIP media policy  310  and VOIP signaling policy  330 . The VOIP media policy  310  includes instructions for VOIP media flows in the forward and reverse directions. The title  312  is (FL &amp; RL) for VOIP media. Precedence  314  is equal to one. The gateway  112  uses the precedence associated with various policies to determine which installed policy to follow. As will be seen, all of the other installed policies have a precedence value higher than 1, thus the static policy  260  will not be preferred by the gateway  112  after the other polices are installed. 
     The ROHC attribute  318  is set to mark flows for compression. This setting instructs the gateway to mark voice packet headers for compression. ROHC refers to robust header compression and is one form of compression that may be used with embodiments of the present invention. ROHC is particularly well suited for header compression of packets transferred over a wireless network. As stated previously, other header compression methods could be used. 
     The Differentiated Services Code Point (DSCP) policy  320  is set to copy from user datagram. The user datagram contains information about a user associated with a mobile-communication device. The DSCP policy is used by the gateway to classify packets and determine the preference given to data packets associated with the policy. The flow ID  322  is set at none. At this point in the call set up, the media flow has not yet been set up so a flow ID is not available. The filter rules  324  represent default filter rules that are very general. 
     VOIP signaling policy  330  governs the flow of VOIP signaling to and from the gateway  112 . The title  332  is (FL &amp; RL) for VOIP signaling. The type attribute  336 , the ROHC attribute  338 , the DSCP policy attribute  340 , the flow ID attribute  342 , and the filter rules  344  are identical to those described with reference to the VOIP media policy  310 . The precedence attribute  344  is set to two. As described previously, the policy associated with the highest precedence will be selected by the gateway  112  to govern the associated data flow. In this case, it is not important that the precedence is set specifically to two but that the precedence is greater than the precedence associated with the VOIP media policy  310  and less than the precedence associated with the other polices that are yet to be described. 
     Turning now to  FIG. 4 , the signaling traffic-flow-template policy  262  is described in accordance with an embodiments of the present invention. The signaling traffic-flow-template policy  262  includes a forward policy  410  and a reverse policy  430 . The forward policy  410  governs signaling flow from the gateway  112  to the mobile-communication device  102 . The reverse policy  430  governs flow of data from the mobile-communication device  102  to the gateway  112 . The signaling traffic-flow-template policy  262  may govern the signaling flow during the telephone call. 
     Forward policy  410  is titled  412  “FL policy for VOIP signaling”. The precedence  414  is set to three. As described previously, setting the precedence to three indicates that the forward signaling policy  410  is preferred over policies with a lower precedence. The specific precedence value of three is not important, other than for the fact it is higher than the precedence values associated with previously described policies. The type attribute  416  is set at “TY.” TY is the interface between the gateway  112  and the PCRF  124 . Other types of interfaces may be specified depending on the access network. The ROHC  418  is undefined. The DSCP policy  420  is set to “AF31.” AF stands for assured forwarding. The assured forwarding guarantees a certain amount of bandwidth and allows access to more bandwidth if it is available. As described previously, the DSCP policy governs the priority given to data flows associated with the present policy. Flow ID  422  is set at zero. The flow ID  422  identifies data packets belonging to a specific flow by adding the flow ID to the data packet. Zero is an exemplary flow ID value and any value associated with a particular flow could be included. The policy would then govern flows with the associated flow ID. Traffic policing  424  is set to “assign minimal bandwidth based on customer network.” The traffic policing setup allows the network to allocate bandwidth for signaling based on network usage. The filter rule  426  is again a standard protocol. If an actual phone call were being setup, the “IMS signaling port range” would include the numbers of actual ports. 
     Reverse policy  430  is titled RL Policy for VOIP signaling. The precedence attribute  434 , the type attribute  436 , the ROHC attribute  438 , the DSCP policy attribute  440 , the flow ID  442 , and the traffic policing  444  contain the same attribute values as described above with reference to the forward policy for VOIP signaling  410 . Filter rule  446  is essentially the same as filter rule  426  except that it specifies an IMS signaling port range that includes the destination ports. 
     Turning now to  FIG. 5 , the bearer traffic-flow-template policy  264  is described in accordance with embodiments of the present invention. The bearer traffic-flow-template policy  264  includes a forward policy  510  and the reverse policy  530 . The forward policy  510  governs the flow of voice packets from the gateway  112  to the mobile-communication device  102 . The precedence attribute  514  is four. This gives forward policy  510  precedence over the previously described policies. As described previously, the policy with the highest precedence level will be implemented by the gateway  112  to govern the associated data flow. The type attribute  516  is set at TY. The ROHC attribute  518  is set as mark flows for compression using new AVP (attribute value pair). Two new attribute value pairs are used to mark the flows for compression. The first AVP enables or disables header compression. The second AVP describes the mode of header compression to be used in compressing the header associated with voice packets. Various methods of compressing a voice packet header are known in the art and may be designated as the compression mode. 
     The DSCP policy  520  is set at EF (“express forwarding”). The EF policy has a higher priority than the AF31 designated by previously described policy. This means that data packets associated with forward policy  510  would be given priority over other data packets associated with a DSCP set to AF31. The flow ID  522  is set to one. The traffic policing  524  is set to “assign minimal bandwidth based on customer network.” The filter rule  526  is a generic filter rule that designates a range of ports that can be used by the ROHC compressed bearer traffic. 
     The reverse policy  530  has a title  531  of RP policy for ROHC traffic. The reverse policy governs the media flow received by the gateway  112 . The reverse policy  530  includes a precedence  532  of four, the type  534  is “TY,” the ROHC is set to marking flows for compression using the AVPs previously described, a DSCP policy  538  is set to EF and a flow ID  540  is set to one. The traffic policing  542  is also set to “assign minimal bandwidth based on customer network.” The filter rule  544  is the same as filter rule  526  except that it designates port ranges to which data packets are sent rather than ports from which data packets leave the gateway  112 . 
     Turning now to  FIG. 6 , the header compression policy  266  is described in accordance with an embodiment of the present invention. The header compression policy  266  includes a VOIP signaling policy  610  and a VOIP media policy  630 . The VOIP signaling policy governs signaling flow while the phone call is active. The VOIP media policy  630  governs the voice packets. 
     The title of VOIP signaling policy  610  is policy for VOIP signaling. The precedence attribute  614  is set to 5. The precedence of five ensures that this policy will be given precedence over all other policies previously described. Thus, policy  610  will be the policy governing signaling once the call is fully set up. The type  616  is set to TY. The ROHC  618  is set to mark flows for compression using the new AVPs. The new AVPs have been described previously to include an AVP that activates the compression and an AVP that designates the mode of header compression. The DSCP policy  620  is set to EF. The flow ID  622  is set to none. In this case, the session ID (not shown) would be used to match the flow with the policy. 
     The traffic policing  624  is set to assign bandwidth based on subscriber class. This attribute allows the policy to accommodate a tiered subscriber class. For example, a gold member could be given more bandwidth than a silver member. The filter rules  626  specifies a particular source IP address and a destination IP address that represent the end points of the telephone conversation. One of the end points would be the mobile-communication device  102 . The filter rule will also designate a specific ROHC RTCP (Real-time Transport Control Protocol) port by number. The ROHC rtcp port that is designated would be one of the ports within the range designated in filter rule  526  in policy  510 . 
     The VOIP media policy  630  has a title attribute  632  of Policy for VOIP Media. The precedence value  634  is five. This indicates that the VOIP media policy  630  will govern flow of VOIP media associated with the policy. The type  636  is set to TY. The ROHC attribute  638  is set to mark flows for compression using the new AVPs, which have been described previously. The DSCP policy  640  is set to EF. The flow ID  642  is set to none for reasons described previously with reference to VOIP signaling policy  610 . The traffic policing  644  is set to assign bandwidth based on subscriber class as described previously. The filter rule  646  is the same as the one described previously with reference to filter rule  626 . 
     Turning now to  FIG. 7 , a method of setting up a wireless telephone call utilizing VOIP technology with dynamically adjustable bandwidth allocation based on tiered subscriber service is shown, in accordance with an embodiment of the present invention. At step  710 , a static policy is installed on a gateway. As described previously, the static policy may be installed in conjunction with setting up the main connection between a mobile communication device and a gateway. 
     At step  720 , a signaling policy is installed on the gateway. The signaling policy may be pushed to the gateway from a PCRF. A signaling policy contains instructions for handling signaling traffic during the wireless telephone call. The gateway will follow the instructions on the signaling policy as long as the signaling policy is installed on the gateway and has a higher precedence than other policies governing signaling. At step  730 , a bearer policy is installed on the gateway. The bearer policy includes instructions on how to handle voice packets as part of the wireless telephone call. The bearer policy may be installed after a media connection or in conjunction with a media connection being made. At step  740 , a header compression policy is installed on the gateway. The header compression policy may include a first attribute value pair that defines header compression parameters for the voice packets governed by the header compression policy. A second attribute value pair may instruct the gateway to allocate bandwidth for the wireless telephone call according to a subscriber service level associated with the mobile communication device participating in the wireless telephone call. This combination of attributes allows a wireless telephone call using VOIP technology to be set up such that header compression is possible along with the dynamic allocation of bandwidth based on subscriber class. In one embodiment, the header compression parameters include the specification of a header compression mode. The header compression parameters may also include an activation status that may activate or deactivate header compression. In one embodiment, each policy is associated with a precedence. The header compression policy may have the highest precedence, the bearer policy the second highest precedence, the signaling policy the third highest precedence, and the static policy the lowest precedence. Policies with a higher precedence will be preferred by the gateway in determining how to handle associated media and signaling data. 
     Once a call has been terminated, the header compression policy may be uninstalled first. Subsequently, the media connection may be terminated. After the media connection has been terminated, the bearer policy may be uninstalled. After the bearer policy is uninstalled the signaling connection may be terminated. After the signaling connection is terminated, the signaling policy may be uninstalled. Finally, the main connection is terminated and the static policy may be uninstalled. 
     Turning now to  FIG. 8 , a method of setting up a wireless telephone call utilizing VOIP technology with dynamically adjustable bandwidth allocation based on tiered subscriber service is shown and designated generally with numeral  800 . At step  810 , a main connection between a mobile communication device and a gateway is established. At step  820 , a static policy is installed on the gateway that governs the signaling during setup of the wireless telephone call. At step  830 , a signaling connection between the mobile communication device and a call flow component that establishes a communication session is established. In one embodiment, the call flow component is a CSCF. At step  840 , a signaling policy is installed on the gateway to provide a traffic flow template for VOIP signaling traffic. At step  850 , a media connection between the mobile communication device and a different communication device participating in the wireless telephone call is established. The media connection carries voice traffic as voice packets. 
     At step  860 , a bearer policy is installed on the gateway to provide a traffic-flow-template for the voice traffic. The bearer policy specifies a bandwidth allocation based on a subscriber class associated with the mobile communication device. The bearer policy may also instruct the gateway to perform header compression on the voice packets. At step  870 , a header compression policy is installed on the gateway. The function of the header compression policy has been described previously. As described previously, once the telephone call is terminated the policies and connections may be terminated or uninstalled in the reverse order. 
     Many different arrangements of the various components depicted, as well as components not shown, are possible without departing from the spirit and scope of the present invention. Embodiments of the present invention have been described with the intent to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. A skilled artisan may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present invention. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need be carried out in the specific order described