Patent Publication Number: US-2010128662-A1

Title: Dynamic real-time quality management of packetized communications in a network environment

Description:
CROSS REFERENCE TO RELATED PATENTS/PATENT APPLICATIONS 
     Continuation Priority Claim, 35 U.S.C. §120 
     The present U.S. Utility Patent Application claims priority pursuant to 35 U.S.C. §120, as a continuation, to the following U.S. Utility Patent Application which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility Patent Application for all purposes: 
     1. U.S. Utility application Ser. No. 10/779,838, entitled “Dynamic real-time quality management of packetized communications in a network environment,” (Attorney Docket No. BP2970.1), filed 02-17-2004, pending, which claims priority pursuant to 35 U.S.C. §119(e) to the following U.S. Provisional Patent Application which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility Patent Application for all purposes:
         a. U.S. Provisional Application Ser. No. 60/472,647, entitled “Method for handoff of a telephone call between two different wireless networks,” (Attorney Docket No. BP2970.1), filed 05-22-2003, now expired.       

    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     The present invention relates generally to communication networks supporting multimedia packetized communications, and more particularly to a system for managing the quality of service provided by a wireless local area network. 
     2. Description of Related Art 
     Communication technologies that network electronic devices are well known. Examples include wired packet data networks, wireless packet data networks, wired telephone networks, and satellite communication networks, among other networks. These communication networks typically include a network infrastructure that services a plurality of client devices. The Public Switched Telephone Network (PSTN) is probably the best-known communication network and has been in existence for many years. The Internet, another well-known example of a communication network, has also been in existence for a number of years. Communication networks like these enable client devices to communicate with one another on a global basis. 
     Local Area Networks (wired LANs), e.g., Ethernets, support communications between networked computers and other devices within a serviced area. These wired LANs often link serviced devices to Wide Area Networks (e.g., WANs) and the Internet. Each of these networks is generally considered a “wired” network, even though some of these networks, e.g., the PSTN, may include some transmission paths that are serviced by wireless links. 
     Wireless networks have come into existence more recently. Examples include cellular telephone networks, wireless LANs (WLANs), and satellite communication networks. Common forms of WLANs such as IEEE 802.11(a) networks, IEEE 802.11(b) networks, and IEEE 802.11(g) networks are referred to jointly as “IEEE 802.11 networks.” In a typical IEEE 802.11 network, a wired backbone couples to a plurality of wireless Access Points (APs), each of which supports wireless communications with computers and other wireless terminals that include compatible wireless interfaces within a serviced area. The wired backbone couples the APs of the IEEE 802.11 network to other networks, both wired and wireless, and allows serviced wireless terminals to communicate with devices external to the IEEE 802.11 network. Devices that operate consistently with an IEEE 802.11 protocol may also support ad-hoc networking in which wireless terminals communicate directly to one another without the presence of an AP. 
     Currently, Wireless Local Area Networks (WLANs) service a wide variety of data communications, typically relating to non-real-time requirements. As the bandwidth delivered on the wireless links serviced by the WLANs increases, additional data communications may also be delivered, e.g., Voice Over Internet Protocol (VOIP), video conferencing, multi-media streaming, etc. However, when the WLAN supports many data transactions, the communications requiring continual throughput such as voice and multimedia communications may not be sufficiently serviced. The result of this shortcoming is reduced voice and video image quality, disconnection of the serviced communication, etc. 
     The shortcomings of the WLAN may be at the APs that service the wireless links within the WLAN. Each WLAN supports only a maximum throughput, e.g., 11 Mbps (Mega-bits per second) for IEEE 802.11b APs and 54 Mbps for 802.11a and 802.11g APs. When a particular AP cannot service all of its client devices, latency in the communications will increase. Because the AP cannot typically assign priority to its serviced communications, some or all of the serviced communications are adversely affected. 
     The performance of the WLAN may also be affected by the switches, routers, nodes or other elements in the backbone network of the WLAN and/or gateways that couple the WLAN to a WAN, to the Internet, to the Public Switched Telephone Network (PSTN) or to another servicing network. When these devices become overloaded, the WLAN serviced communications are also affected. Additionally, traffic within individual network segments may adversely impact communications. 
     WLANs often serve as terminating networks for voice communications, multimedia communications, etc. In some operations, the WLANs perform adequately but a network that couples the WLANs does not. An example of such an installation is when two offices of a major corporation each have WLAN service and a WAN couples the WLANs. In order to reduce telephony costs, voice traffic is routed across the WAN. When voice quality suffers, the WLAN administrators most likely identify the WLAN components as the problem even though the WAN itself may be the bottleneck. This troubleshooting most often occurs when reported by a user after the fact. By that time, the WAN problem may have been remedied and the system administrator can offer no solution. Such is also the case when the APs or other WLAN components are temporarily overloaded. 
     Thus, a need exists for intelligent systems and components that can identify network or pathway problems in real-time and effect real-time solutions. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to apparatus and methods of operation that are further described in the following Brief Description of the Several Views of the Drawings, the Detailed Description of the Invention, and the claims. Other features and advantages of the present invention will become apparent from the following detailed description of the invention made with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       For a more complete understanding of various aspects of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numerals indicate like features and wherein: 
         FIGS. 1A and 1B  depict communication pathways between wireless terminals and far end terminals; 
         FIG. 2  provides a block diagram that details the functions of the wireless terminal of  FIGS. 1A and 1B ; 
         FIG. 3  depicts an embodiment where an individual wireless terminal selects a communication pathway, selects a wireless link to an access point providing the highest level of service; 
         FIGS. 4A-4E  provide block diagrams depicting the functions of various embodiments of wireless terminals; 
         FIG. 5A  depicts a flow chart detailing the processes associated with selecting the appropriate coding scheme for outgoing user communications; 
         FIG. 5B  depicts the selection of a coding scheme associated with incoming communications at the wireless terminal; 
         FIG. 5C  depicts a process by which incoming and outgoing communications are received and the coding scheme and communication pathway are monitored and evaluated for potential changes which would improve the measured and perceived quality of the serviced communication; 
         FIGS. 6A and 6B  depict an embodiment wherein the decision making process may be executed by a processor within either an access point or a quality monitoring module; 
         FIG. 7A  depicts the internal functions of a wireless AP having the ability to monitor and make quality decisions on the exchange of packetized communications through the wireless AP; 
         FIG. 7B  depicts a quality-monitoring module located within the network. The module is capable of monitoring, evaluating and acting on information contained within the communication signatures of packetized communications passing through the quality monitoring module; 
         FIG. 8A  provides an ideal communication signature of real-time packetized communications; 
         FIG. 8B  provides one example of a non-real-time data communication involving bursts of data; 
         FIGS. 8C and 8D  depict real communication signatures wherein packets of data are dropped; 
         FIGS. 9A and 9B  illustrates the perceived and measured quality level impacts of the dropped packets in  FIGS. 8C and 8D ; 
         FIG. 10  depicts that packets are typically lost in bursts; 
         FIG. 11A  provides an ideal communication signature wherein a real-time communication is received in packet sequence order; 
         FIG. 11B  depicts a real communication signature wherein packetized communications are dropped via the wireless link between the wireless terminal and the access point; 
         FIG. 12A  depicts a real communication signature wherein packetized communications are dropped within the network communication pathway; 
         FIG. 12B  depicts a real communication signature wherein packets are received out of order from the network; and 
         FIGS. 13A and 13B  depict process flows associated with quality monitoring. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred embodiments and aspects of the present invention are illustrated in the figures, like numerals being used to refer to like and corresponding parts of the various drawings. 
       FIG. 1A  provides a diagram illustrating a wireless terminal  10  wirelessly coupled to WLAN  12  through AP  14 .  FIG. 2  further details wireless terminal  10 . Processing unit  16  within wireless terminal  10  couples to and directs the functions of wireless interface  18  that communicatively couples to AP  14 . Additionally, processing unit  16  couples to and directs programmable COder/DECoder (CODEC)  20  to convert user information or communications received at user interface  22  into packetized communications. User interface  22  may take the form of a microphone  25 , camera  26 , or other like device to receive audio and/or visual input from a user. Additionally, the user interface  22  may include a display  28 , speaker  30 , or other like device to present audio and/or visual information to the user. Packetized communications  24  are exchanged between wireless terminal  10  and AP  14 . 
     As shown in  FIG. 1A , AP  14  broadcasts within WLAN  12  and couples to backbone network  15 . As shown, backbone network  15  couples to a wide area network (WAN)  32  that in turn relays the packetized communications to far-end terminal  34 . In this first instance, far-end terminal  34  is serviced by a remote wireless local area backbone network  40  having AP  42 . It should be noted that the far-end terminal  34  need not be limited to a wireless terminal. For example, a wire-based telephone such as that illustrated in  FIG. 1B  may act as the far-end terminal. In this example, backbone network  15  couples to the public switch telephone network (PSTN)  36  via a private box exchange (PBX)  38  and delivers audio communications to a far-end terminal  34 . 
     Returning to wireless terminal  10  of  FIG. 2 , processing unit  16  monitors the packetized communications  24  exchanged between wireless terminal  10  and AP  14  in order to determine a communication quality level delivered by the wireless link that couples wireless terminal  10  to AP  14 . Once the communication quality level delivered by wireless link  40  has been determined, processing unit  16  specifies the coding scheme to be employed by CODEC  20  to convert user communications into packetized communications  24 . Additionally, processing unit  16  may communicate with far-end terminal  34  to determine the overall delivered communication quality level along the entire communication pathway. Then processing unit  16  can select the coding scheme based on the overall delivered communication quality level. 
     Some example coding schemes used in audio or video coding include Huffman encoding, ITU-T G.711, u-law, A-law, CCITT G.721, CCITT G.723, ITU-T G.726, ITU-T G.723.1, ITU-T G.723.1A, ITU-T G.729, ITU-T G.729A, ITU-T G.729AB, ITU-T G.729E, ITU-T G.728, ITU-T G.722, ITU-T G.722.1, ITU-T G.722.2, GSM-EFR, GSM AMR, IMA/DVI ADPCM, Microsoft ADPCM, LPC-10E, CELP GSM 06.10, shorten, Real Audio, MPEG, ACE and MACE, as well as others known to those skilled in the art. Wireless terminal  10  receives packetized communications  24  wirelessly via antenna  52 . Wireless interface  18  exchanges the incoming communications with jitter buffer  54 . Processing unit  16  monitors jitter buffer  54  to determine its latency. This information may be used to determine the communication quality level delivered by wireless link  40 . Based on the measurement of the communication quality level delivered, processing unit  16  may change the selected coding scheme used by CODEC  20  to convert user communications received to and from packetized communications. 
     Processing unit  16  may also monitor various signal pathways in its decision-making process.  FIG. 3  depicts a situation wherein wireless terminal  10  has access to APs  14 A,  14 B and  14 C that each couple to wireless local area backbone network  15 . This allows processing unit  16  to choose its servicing AP based upon the expected service quality level supplied by individual APs  14 A,  14 B and  14 C. In one instance, this process involves monitoring a number of APs by querying each available AP to determine the service quality level delivered by each individual AP. Wireless terminal  10  then chooses a new AP when the service quality level provided by the new servicing AP exceeds the service level provided by the current servicing AP by a predetermined service level. 
       FIGS. 4A-4D  provide block diagrams illustrating the typical components of various wireless terminals.  FIG. 4A  depicts wireless terminal  400  as having only a short-range digital radio WLAN RF unit  404 A that supports Bluetooth® or like wireless communications with the WLAN.  FIG. 4B  includes a cellular RF unit  404 B that supports wireless communications with the cellular network.  FIG. 4C  includes a WLAN RF unit  404 A and satellite RF unit  404 C.  FIG. 4D  includes WLAN RF unit  404 A, cellular RF unit  404 B, and satellite RF unit  404 C. RF units,  404 A,  404 B and  404 C couple to antennae  402 A,  402 B and  402 C respectively. These antennae  402 A,  402 B, and  402 C may be located internal or external to the case of the wireless terminal  400 . Further, in some embodiments, a single RF unit and/or a single antenna may support communications with both the WLAN and the cellular network. Processor  406  may be an Application Specific Integrated Circuit (ASIC) or another type of processor capable of operating the wireless terminal  400  according to this disclosure. Memory  408  includes both static and dynamic components, e.g., DRAM, SRAM, ROM, EEPROM, etc. In some embodiments, the memory  408  may be partially or fully contained within an ASIC that also includes the processor  406 . A user interface  410  includes a display, indicators, a keyboard, a speaker, a microphone, and/or a data interface, and may include other user interface components known to those still in the art. RF interfaces  404 A,  404 B, and  404 C, processor  406 , memory  408 , and user interface  410  couple via one or more communication buses/links  416 . Battery  412  or power port  418  couples to and powers RF interfaces, processor, memory and the user interface. 
       FIG. 5A  provides a flowchart that depicts the servicing of real-time communications through a wireless terminal. At Step  500 , outgoing communications are received at the user interface of the wireless terminal. These user communications may take the form of either audio or visual communications. An initial coding scheme, selected at Step  502 , is utilized to code outgoing communications into packetized communications at step  504 .  FIG. 5B  depicts incoming communications and utilizes the coding scheme to convert the incoming packetized communications to a format more readily used by the user. Outgoing packetized communications are exchanged between the wireless terminal and servicing AP at a given packetized rate in Step  506 . This exchange is monitored in Step  508  to determine the communication quality level supported between the AP and the wireless terminal. By monitoring the exchange of packetized communications between the AP and the wireless terminal, the maximum delivered communication rate between the AP and the wireless terminal may then be used at decision point  510  to determine if the measured or perceived service can be improved by selecting a new coding scheme. If an improvement can be effected, a new CODEC is selected at step  512  and used in step  504  to convert new user communications into packetized communications. Otherwise, the processor continues to monitor the exchange of packetized communications in step  508 . 
       FIG. 5B  provides a flow chart illustrating the processes associated with receiving incoming packetized communications at the wireless terminal via the AP. At step  520 , incoming packetized communications from the network are received at the wireless terminal. The processor identifies the coding scheme associated with these packetized communications in step  522 . These communications are converted into user communications at step  524  and provided to the user through an interface at step  526 . Simultaneously, the device monitors the communication quality level between the wireless terminal and the AP, and potentially the far-end terminal in step  528 . 
     During the monitoring, a continuous evaluation is made as to whether or not the measured or perceived service can be improved with an alternative coding scheme at decision point  530 . If it cannot, monitoring continues at step  528 . Otherwise, a new coding scheme is selected in step  532 , and implemented with the far-end terminal in step  534 . New communications received should then be coded in accordance with the selected coding scheme as the process begins again at step  520 . 
       FIG. 5C  illustrates the receipt of incoming and outgoing communications at a user interface in step  550 . An initial coding scheme, selected at step  552 , is employed in step  554  to translate between user communications and packetized communications. Packetized communications are exchanged between the wireless terminal and the APs at step  556 . As previously stated, the exchange process is monitored to determine the delivered communication quality level between the wireless terminal and APs in step  558 . At decision point  560 , a determination is made as to whether or not a need exists to revise the CODEC. The revised CODEC is selected and implemented in steps  562  and  564  respectively. Otherwise, the processor continues to monitor the exchange of packetized communications. 
     The monitoring process may also evaluate the communication pathways used to exchange packetized communications between the wireless terminal and the far-end terminal in step  566 . Alternatively, communications between both end points may determine the appropriate CODEC or communication pathway. The process answers this question at decision point  568  and implements changes at step  570  or continues to evaluate at step  566 . 
     In this embodiment, the overall communication quality level delivered across the entire communication path maybe evaluated. The decision to revise the selected CODEC at the above decision points now may consider the overall communication quality level and/or network/hardware considerations. Additionally, communications between the wireless terminal and the far-end terminal may identify a CODEC supported by both the far-end terminal and wireless terminal. 
     The process of monitoring packetized communications between end points may include monitoring the latency of packetized communications within the jitter buffer within the wireless terminal or VoIP terminal. As will be discussed later, this process may also be repeated or emulated at the AP or various nodes within the communication pathways that link the wireless terminal to the far-end terminal. 
       FIGS. 6A and 6B  detail embodiments where the processing and decision-making process does not need to occur within wireless terminal  10 . Here, wireless terminal  10  is wirelessly linked to AP  600 . AP  600  services WLAN  12 . One embodiment of AP  600  is further detailed in  FIG. 7A . 
     In  FIG. 7A , a wireless connection links wireless terminal  10  to antenna  618  and wireless interface  620  of AP  600 . Processor  622  monitors and directs wireless interface  620 , jitter buffer  624 , and network interface  628 . Processor  622  identifies and examines the communication signatures of packetized communication from wireless terminal  10  to determine if the communication is a real-time communication or non-real-time communication. A priority based on the communications real-time requirements is assigned for the serviced communication. Additionally, processor  622  evaluates the coding scheme and communication pathways used between wireless terminal  10  and the intended far-end terminal. Processor  622  determines how the communication should be routed and assigns a coding scheme and communication pathway that provides a predetermined level of service for the real-time communication. Furthermore, processor  622  may communicate with wireless terminal  10  in order to direct which coding scheme is to be used by the programmable CODEC, with the terminals. 
     In one example, processor  622  may examine the packetized communications exchanged between wireless terminal  10  and wireless interface  620  to determine the communication quality level delivered by the wireless link. When the wireless link is limiting, processor  622  may employ a coding scheme based on the communication quality level delivered by the wireless link. Additionally, by examining jitter buffer  624 , processor  622  determines the latency associated with these buffers and assigns an appropriate coding scheme based on that latency. Processor  622  also interfaces with network interface  628  to direct the exchange of packetized communications between AP  600  and the backbone network or other network components in the communication pathway between wireless terminal  10  and the destination terminal. 
     These same processing functions may be achieved with a quality-monitoring module  602  further detailed in  FIG. 7B . If the WLAN AP with which the wireless terminal communicates does not have the ability to monitor and evaluate packetized communications, these functions may be supported by quality monitoring module  602 . Additionally, these modules, when located at nodes within the pathway, may supplement the functions of APs having these abilities. 
       FIG. 7B  shows that network communications maybe received at network interface  628 A via port  630 A. As previously stated, the network interface couples to processor  622  and jitter buffer  624 . The communications then pass from network interface  628 B and ports  630 B to the other segments in the network. 
     Returning to  FIG. 6A , it should be further noted that quality-monitoring modules  602  might be located within any network segment or at any network vertices such as those between backbone network  604  and WAN  606 , as well as backbone network  608  and WAN  606 .  FIG. 6A  shows that wireless terminal  10  communicates with far-end terminal  614  along the communication pathway shown. It should be understood that the monitoring modules are optional as AP  600 , as configured in  FIG. 7A , has the ability to process and evaluate the packetized communications exchanged between the network and wireless terminal  10 . 
       FIG. 6B  includes a bypass network such as PSTN, cellular, satellite, or other like network known to those skilled in the art. In this instance, quality-monitoring modules  602  may direct that if the primary communication pathways are unable to support the real-time communications between wireless terminal  10  and far-end terminal  614 , then a bypass network  606 B, such as one or more of those identified above may be used in favor of WAN  606 A. Quality monitoring modules  602 , in addition to evaluating communication quality levels delivered by the network, and the coding schemes employed, may further direct that non-real-time communications receive a lower priority or be temporarily stored in a buffer, or be delayed to support real-time communications. 
     One process accomplished by processor  622  in either AP  600  or quality monitoring module  602  is to determine whether or not the communications received from wireless terminal  10  are above or below a predetermined communication quality level threshold. The determination as to whether or not the communications are real-time communications or non-real-time communications may be determined by the protocols associated with the communications. For example, RTP protocols may identify real-time communications.  FIG. 8A  provides an example of an ideal packetized communication signature associated with a real-time communication from the wireless terminal.  FIG. 8B  depicts one possible signature of data communications that contain large amounts of data in relatively small bursts  804 . Thus, the processor may also evaluate these communication signatures to determine which communications are real-time communications and to assign a predetermined level of service to those real-time communications. This evaluation of the communication signature is important where non-real-time protocols are used to convey real-time communications. 
       FIGS. 8C and 8D  show real-time communications with some data loss. Losses of individual packets of packetized communications impact the quality that the user perceives at the wireless terminal. It is important to maintain a perceived level of quality for the end user. This results in subscriber retention and increased user satisfaction. Ideally, VoIP systems should approach or exceed the quality of traditional telephony systems. 
       FIGS. 9A and 9B  depict the effects of the dropped packets in  FIG. 8C and 8D  on the user&#39;s perceived quality.  FIG. 9A  shows that packet sequence  2  is lost as indicated by the gap L 1 . Gap L 2  indicates the loss of packet sequence  7 . These losses result in a reduced overall quality. Line  650  indicates the measured communication quality while dotted line  652  indicates the user&#39;s perceived communication quality. Line  650  depicts the measured communications quality as varying between a high quality and a low quality. Somewhere in between is a minimum average service to be maintained in order to ensure end user satisfaction.  FIG. 9B  depicts an instance when the same number of packetized communications is lost. However the packets lost are consecutive or form a burst at gap L 1 . This loss has a much more pronounced effect on the user&#39;s perceived quality of the communications than the small non-burst losses seen in  FIG. 9A .  FIG. 9B  depicts a large gap wherein the perceived quality  652  dropped below the minimum service level for the communications. The fact that lost packets typically occur in bursts is indicated by the data represented in  FIG. 10  wherein consecutive lost packets versus packet sequence number are provided. Spikes  660  indicate large losses of data. These typically are large consecutive losses of packetized communications. 
     The time that it takes for the perceived quality of the communications to rise above a minimum acceptable level is a function of the recovery from the loss of data, and the coding scheme used. Some coding schemes may more quickly compensate for recently lost packets.  FIG. 11A  depicts an ideal communication signature between a wireless terminal and an AP wherein a real-time communication having a series of packetized communications  24  are received in the proper packet sequence order and contain approximately the same amount of information. In contrast,  FIG. 11B  depicts one example of a real communication signature between the wireless terminal and the AP wherein some packetized communications  24  are dropped in packet sequence order. 
     Thus, the quality monitor for the signatures depicted in  FIGS. 11A and 11B  may choose different coding schemes.  FIG. 11A  does not require a rapid recovery from dropped packets. However,  FIG. 11B  requires the processors to select the scheme that provides the highest level of perceived quality and minimizes the effect of dropped packets. Additionally, the quality monitor may seek to service a wireless terminal with an alternative AP in order to avoid dropped packetized communications if a second AP is available to provide a higher level of service. 
     Network communications received from the far end terminal by the quality monitor should be received in packet sequence order and in a timely fashion. However,  FIG. 12A  provides the communication signature of packetized communications received from another segment in the network when packets are dropped.  FIG. 12B  depicts a communication signature wherein packets are received out of packet sequence order. Both instances may affect the perceived quality of the communication; the quality monitor may evaluate these communication signatures and direct an appropriate course of action. For example, in  FIG. 12A , where packetized communications  24  that correspond to packet sequence nos.  2  and  7  are dropped in order, the quality monitor may elect a coding scheme better suited to maintain a high level of perceived quality when occasional packetized communications  24  are dropped. Additionally, when packetized communications  24  contain routing information, a determination can be made as to the network segment at which the packetized communications corresponding to the dropped packet sequence numbers. Then, the dropping network segment may be removed if possible from the communication pathway. In an instance where this is not possible, the quality monitor may direct an alternative communication pathway such as that provided by bypass network  606 B of  FIG. 6B . 
       FIG. 12B  indicates that while no packetized communications  24  were dropped, latency problems caused the packetized communications to be received out of sequence. As shown here, the packetized communications corresponding to packet sequence nos.  7 ,  6 ,  5 , and  2  were received out of order. In certain cases, these packets will be discarded. These packetized communications are analyzed to determine the root cause of their delay and the network impediment, which may be removed, if possible, or a coding scheme revised to handle packetized communications received out of order while still allowing the perceived quality of the communication to remain high. Alternatively, a bypass network may be utilized if reconfiguring the communication pathway and revising the coding scheme does not provide the desired level of service. 
       FIG. 13A  provides a process flow by which the quality monitors associated with either the APs or quality-monitoring modules within the network are able to receive outgoing communications at the quality monitor (processor) in step  700 . The quality monitor determines, based on the communication signature associated with the outgoing communications, whether or not the communication is a real-time communication in step  702 . In which case, real-time communications are prioritized at step  704  and non-real-time communications may be delayed dependent upon the bandwidth requirement of current communications. Then, a coding scheme consistent with the communication signature or communication pathway consistent with the communication signature may be selected at step  706 . The process continually repeats for ongoing communications in order to ensure that the highest possible levels of communications are provided to the end user. 
       FIG. 13B  also provides a process flow wherein communications are received by a quality monitor at Step  720 . Communications signatures are analyzed at Step  722  in order to prioritize the communications and send them to their intended destination at steps  724  and  726  respectively. The quality monitor continuously monitors these communications at step  728  and evaluates whether or not service can be improved with either a new communication pathway or coding scheme at step  730 . If service may be improved, the necessary change is implemented at step  732 . Otherwise, the evaluation process continues at step  728 . 
     In summary, this disclosure provides the ability to incorporate quality monitors either into wireless terminals, wireless access points, or other network modules. These quality monitoring functions monitor, in real-time, the measured and perceived quality of real-time communications. In addition to monitoring these levels of quality, communication pathways and coding schemes may be dynamically reconfigured to improve the measured and perceived level of quality. This has particular applications to VOIP and other like streaming multimedia applications. Such applications enable providers to maintain a high level of user satisfaction while minimizing the impact on network resources. Additionally, quality monitors support dynamic mixed usage of network bandwidth such that voice data and other multimedia communications are prioritized based on their immediate need when compared to other data communications. Thus, the quality monitors support dynamic bandwidth sharing amongst the different types of communications. This ability minimizes network-operating costs and provides real-time communications such as VOIP at quality levels that can reach or exceed traditional telephony levels. 
     In some embodiments, a system and method are operable to service real-time audio and/or visual communications in a network environment that are negatively impacted by packet delay or packet losses, such as Voice over Internet Protocol (VoIP) or wireless terminals that transmit and receive communications in a digital form having discrete packets. More specifically, various aspects of the present invention provides a dynamic real-time quality management of packetized communications in a network environment. Various solutions presented herein may involve dynamically altering coding schemes, network pathways or dynamically assigning priorities to network communications. 
     Packetized communications are monitored by and exchanged between wireless Access Points (APs) and wireless terminals or a wired terminal, such as a VoIP telephone, and a servicing network. Alternatively, the packetized communications are relayed by quality monitoring modules located within network segments or at network vertices. The processing unit analyzes the packetized communications to identify communication signatures associated with the packetized communications. The processor then uses these signatures to identify network impediments to the exchange of the packetized communications. These impediments may take the form of coding problems in which case an appropriate coding scheme is selected and implemented. Alternatively, the communication signatures may indicate network (traffic) or hardware problems within specific segments of the communication pathway. In this case, traffic is prioritized or rerouted. 
     One embodiment provides an intelligent Wireless Local Area Network (WLAN) Access Point (AP). A second embodiment provides an intelligent VoIP network interface. While, a third embodiment provides an intelligent quality-monitoring module. In the instance of a WLAN AP or intelligent VoIP network interface, the WLAN AP or intelligent VoIP network interface performs the functions of the quality-monitoring module. A wireless interface exchanges packetized communications with wireless terminals on the WLAN. A processing unit couples to the wireless interface and to the WLAN&#39;s backbone network interface, and monitors the exchange of communications serviced by the WLAN AP. The processing unit identifies the communication signature for the packetized communications. Then the processing unit determines, based upon the corresponding communication signature, when the packetized communications are real-time communications. Communications identified as real-time communications are assigned a predetermined service level. The service level assigned to non-real-time communications may be lower than that of the real-time communications. 
     When the real-time communications cannot be provided the predetermined service level, the processor may direct the real-time communications to be re-routed via another servicing network. Alternatively, the processor may direct that the real-time communications be prioritized over the non-real-time communications. 
     Each packetized communication has a pair of signatures: a receive signature corresponding to communications received from a corresponding wireless terminal via the wireless interface and a transmit signature corresponding to communications received via the WLAN backbone interface and intended for the corresponding wireless terminal. The receive signature is primarily employed to determine whether the packetized communication is a real-time communication. Problems in this signature typically indicate problems with wireless link of AP. 
     The transmit signature usually indicates problems (network impediments) within other portions of the communication path. Such network impediments may result in non-uniformity of receipt of the packetized communications from a near-end wireless terminal. This instance indicates problems in the wireless link. Non-uniformity or non-linearity of receipt of the packetized communications from a far-end terminal indicates problems along the various network pathways between the AP and the far-end terminal. 
     Another embodiment takes the form of a method of servicing real-time communications in a network environment. A WLAN AP receives outgoing user communications from a wireless terminal and incoming user communications for the wireless terminal from a WLAN backbone network interfaced with the AP. These communications are in the form of packetized communications coded according to a coding scheme with a programmable COder/DECoder (CODEC). The programmable CODEC converts incoming user communications from packetized communications and outgoing user communications to packetized communications according to the selected coding scheme. 
     Packetized communications are exchanged between the servicing AP, the WLAN terminal, and the WLAN backbone network, the VoIP terminal, intelligent VoIP network interface and backbone network, or other network elements known to those skilled in the art, at a communication quality level. These communications are monitored to determine the communication quality level delivered between the servicing AP, the WLAN terminal, the WLAN backbone network, and the far-end terminal. The communications quality can be monitored within switches, routers, handsets, nodes, access points or other elements within the network infrastructure known to those skilled in the art. Monitoring the packetized communications from end-to-end supports the management of the coding scheme and routing of the packetized communications. The CODEC or communication pathway may be revised to improve service by selecting one or more new coding schemes based upon the communication quality level delivered or by selecting a new pathway. This communication quality level depends on the jitter experienced by the communications, the number and frequency of lost packets, the arrival or transmission rate of the packetized communications, and other such factors known to those skilled in the art. 
     By monitoring the packetized communications from end-to-end, the method can intelligently manage the selected coding scheme and routing of the packetized communications. For example, in one instance, the processor communicates with a far-end terminal to identify an appropriate coding scheme. These coding schemes may include, but are not limited to audio and/or video coding schemes such as Huffman encoding, ITU-T G.711, u-law, A-law, CCITT G.721, CCITT G.723, ITU-T G.726, ITU-T G.723.1, ITU-T G.723.1A, ITU-T G.729, ITU-T G.729A, ITU-T G.729AB, ITU-T G.729E, ITU-T G.728, ITU-T G.722, ITU-T G.722.1, ITU-T G.722.2, GSM-EFR, GSM AMR, IMA/DVI ADPCM, Microsoft ADPCM, LPC-10E, CELP GSM 06.10, shorten, Real Audio, MPEG, ACE and MACE. 
     In another instance, real or emulated jitter buffers, at any point in the communication pathway, monitor latency. This latency is used to determine the communication quality level between the AP and WLAN terminal, VoIP terminal and intelligent VoIP network interface, or along any network segment. Additionally, the communication quality level delivered between the WLAN terminal and the far-end terminal at any point in the network may also be determined. 
     This information allows the processor to select the route the communications take by choosing which network segments are used to route the communications or which AP is servicing the communication. In the case of the latter, the APs are queried to determine the expected service quality level from each AP. Then, the WLAN terminal registers with a new servicing AP when the expected service quality level to be provided by the new servicing AP exceeds the expected service quality level provided by the servicing AP by a predetermined service quality level. 
     Although the present invention is described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as described by the appended claims.