Abstract:
A qualification and monitoring function ( 604, 606 ) monitors the line conditions of a last mile access network that is connected with a multi-access broadband network. The qualification and monitoring function ( 604, 606 ) sends data to a Resource Manager ( 602 ) of the access network upon request. The monitoring function collects, stores, and analyzes performance data, media conditions and stability data using interpretation filters to derive performance indicators. The conditions of the network are also automatically provided to the resource manager ( 602 ) for immediate attention if the access network conditions exceed predetermined thresholds.

Description:
BACKGROUND OF THE INVENTION 
     Today&#39;s broadband networks are constructed of an interconnection of different transport technologies used for different parts of the network such as access, aggregation, transport, and feeding. 
     The following is a list of acronyms used in the body of the specification and their definitions, which shall apply throughout the specification unless otherwise noted. 
     Acronyms: 
     ADSL Asymmetric Digital Subscriber Line 
     ATM Asynchronous Transfer Mode 
     B2B Business to Business 
     E2E End to End 
     DSL Digital Subscriber Line 
     FTTx Fiber To The x=Home, Node, Cabinet, Building, Curb 
     GbE Gigabit Ethernet 
     GPON Gigabit-capable Passive Optical Networks 
     GSM Global System for Mobile Communications 
     HDTV High Definition Television 
     IP Internet Protocol 
     IPTV Internet Protocol Television 
     IPDSLAM Internet Protocol Digital Subscriber Line Access Multiplexer 
     LQ&amp;M Loop Qualification and Monitoring 
     MPLS Multi-Protocol Label Switching 
     OAM Operation Administration and Maintenance 
     OPEX Operational Expenditure 
     PoP Point of Presence 
     PVC Permanent Virtual Circuit 
     QoE Quality of Experience 
     QoS Quality of Service 
     RM Resource Manager 
     RPC Remote Procedure Call 
     SLA Service Level Agreement 
     SOAP Simple Object Access Protocol 
     SNMP Simple Network Management Protocol 
     VDSL Very High Speed Digital Subscriber Line 
     VLAN Virtual Local Area Network 
     VoIP Voice over IP 
     WCDMA Wide-band Code Division Multiple Access 
     xDSL DSL variants (ADSL, SDSL, etc.) 
       FIG. 1  depicts a high-level block diagram of a broadband network that is constructed of an interconnection of different transport technologies used for different parts of the network. Network connectivity is supported also by a huge number of different connectivity technologies and network protocols. In order for services to be delivered from an operator point of presence (PoP) to the customer premises with a required quality of service, several technologies, and protocols have to work together end-to-end. 
     In such a scenario, a unified operation, administration and management (OAM) system covering the whole workflow from service subscription and service provisioning to service quality maintenance has to interface with all network-parts, which is mostly non-standardized and therefore hard to implement. For the wire-line sector such a system is not standardized and it is up to the wire-line operators to fix their own OAM system solution. 
     Existing wire-line broadband solutions have limitations in supporting features like QoS, mobility and security because there is no unified standardized architecture such as in the mobile sector with GSM or WCDMA (ETSI, 3GPP). Interface descriptions between different technologies are proprietary and non-standardized. This leads to a very scattered workflow when providing services to users and thus to a rather fixed service provisioning models, which leads to broadband network shortcomings, including: 
     No flexible end to end (e2e) service provisioning 
     Low grade of business to business (b2b) interface implementation 
     Low e2e QoS management and SLA assurance 
     Missing interfaces, protocols for automation 
     Low grade of automation during service provisioning, high OPEX 
     Problematic service offer extension 
     No control and/or feedback from the end user about the QoE (perceived QoS by the end user) 
     U.S. Patent Application Publication No. 2002/0039352 discloses a system and method for managing a service in a communication network. A service management system collects quality and/or performance data from the network and compares the collected data with quality and/or performance requirements obtained from a client. A service may be managed by verifying that the network is providing an expected level of service. The service management system, however, appears to communicate with the network using existing, non-standardized interfaces because the larger problem is not discussed or contemplated. 
     The ETSI Technical Specification, ETSI TS 182 019 v0.3.3 (2006-12) entitled, “Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN); Resource and Admission Control Sub-system (RACS); Functional Architecture; Release 2” discusses matters related to resource and admission control, but also appears not to contemplate the problem caused by non-standard interfaces between the performance monitor in the access network and the resource manager in the core network. 
     It would be advantageous to have a system and method for managing access networks connecting to broadband networks that overcomes the disadvantages of the prior art. The present invention provides such a system and method. 
     BRIEF SUMMARY OF THE INVENTION 
     A monitoring function monitors the line conditions of an access network that is connected with a multi-access broadband network. The monitoring function sends data to a Resource Manager (RM) of the access network upon request or following a predetermined timetable. The monitoring function collects, stores, and analyzes performance data, line conditions and stability data using interpretation filters to derive performance indicators. The conditions of the network are also automatically provided to the resource manager for immediate attention if the access network conditions exceed predetermined thresholds. 
     Quality of Service (QoS) and nomadism are monitored end-to-end by a distributed Resource Management function, a Loop Qualification and Monitoring (LQ&amp;M) function/tool (hereinafter, “tool”). Local resource managers responsible for bounded parts of a network are in place and cooperating in order to establish and implement global (network wide) QoS policies and guarantees. An access network Resource Manager is disclosed, that interfaces an access network specific Loop Qualification and Monitoring tool to get support on access network resource-related questions including line performance and stability in the access network. 
     The invention allows for real-time interaction between access nodes and core network management functions to maintain and guarantee QoS and Quality of Experience (QoE) for services. This interaction is enabled through web service-based interfaces. 
     In order to guarantee QoS for a given service-mix, it is necessary to include access network resource status information into resource management decisions during service subscription and service invocation. During service operation, status information (service quality monitoring) is used to check a Service Level Agreement (SLA), which is a means of service assurance. 
     The LQ&amp;M tool pushes information to an associated RM in case the line quality has changed (line faults, change of noise-environment) so the RM can react (failure diagnoses, failure repair, automatic service reconfiguration). 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       In the following section, the invention will be described with reference to exemplary embodiments illustrated in the figures, in which: 
         FIG. 1  depicts a high-level block diagram of a broadband network that is constructed of an interconnection of different transport technologies used for different parts of the network; 
         FIG. 2  depicts a block diagram of a Multi-Service, Multi-Access Network Structure for future broadband networks; 
         FIG. 3  illustrates an access network reference architecture through which multi-access accounts can be used to deliver services according to an embodiment of the present invention; 
         FIG. 4  depicts a Resource Manager and a Loop Qualification and Monitoring tool in accordance with an embodiment of the present invention; 
         FIG. 5  is an exemplary high-level block diagram that illustrates a communication interface between the access network and the Resource Manager in accordance with an embodiment of the present invention; 
         FIG. 6  depicts a high level block diagram of the resource manager, interface and LQ&amp;M in accordance with an embodiment of the present invention; 
         FIG. 7  depicts a high-level diagram of message flow for Use Case  1  in accordance with an embodiment of the present invention; 
         FIG. 8  illustrates a message flow for Use Case  2  in accordance with an embodiment of the present invention; and 
         FIG. 9  depicts the notification function message flow in the LQ&amp;M tool for Use Case  3  in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present invention. 
     A Digital Subscriber Line (DSL) access network is described in the specification and figures to avoid the possibility of confusion. However, those skilled in the art will recognize that various access network types and interface configurations may be used in place of the example DSL access network to accomplish the same outcome. 
       FIG. 2  depicts a possible Multi-Service, Multi-Access Network Structure  200  for future broadband networks. Future broadband wire-line networks consist of different network parts that will need to work together in order to provide multi-service and multi-access data transport. Multi-service means that different services, such as data services (Internet access, file-sharing), speech services (VoIP, voice messaging, gambling) and video-based services (IPTV, HDTV, video conferencing, gaming applications) are offered to users by different service providers. 
       FIG. 3  illustrates an access network reference architecture  300  through which multi-access accounts can be used to deliver services according to an embodiment of the present invention. Typical access media that are installed and used to connect to the customer premise sides are:
         Digital Subscriber Loop (DSL)  302 , i.e. digital data transmission over the telephone loop via ADSL1/2/2+ or VDSL1/2;   fiber to the node, cabinet, curb, building (FTTx) architectures  304 , building point-to-point or multipoint access structures using fiber connections to the proximity of the customers (BPON, GPON), bridging only the very last mile with existing telephone copper lines (VDSL2);   deep fiber to the home (FTTH) architectures  306  where fiber is used from the network providers facilities (central office) all the way to residential or enterprise networks (Gb Ethernet) and   wireless connections, such as wireless local area network (WLAN) or mini-link transporting data via radio connections.       

     Networks are very general in terms of service-mixes, but several other important features can be supported by the structure, for instance:
         Service Flow Separation—Ethernet or IP flows are used rather than fixed connections providing a maximum amount of flexibility in service and delivery constellations;   Quality of Service (QoS)—End-to-end resource negotiation, reservation and authorization means can be implemented via B2B interfaces between service and access provider and different access media allows for different grades of service, and   Nomadism and Mobility: where nomadism is the ability of the user to change his network access point after moving; the flow: principle gives the possibility to access subscribed services anywhere in the access network by user authentication.       

       FIG. 4  depicts a Resource Manager and a Loop Qualification and Monitoring tool in accordance with an embodiment of the present invention. Although DSL is a robust and cheap technology that has become the most popular first mile technology, it is known that the actual transport performance (rate, delay, frame loss rate) heavily depends on the copper quality (line length, diameter, age) and copper environment (binder sizes, connector quality, electromagnetic noise environment) and therefore varies between lines. DSL currently provides sufficient capacity for data and voice services, new services like video and gaming, etc. may require the system to operate at the limit of feasibility. 
     A Resource Manager (RM)  402  is connected to a DSL-specific Loop Qualification and Monitoring tool (LQ&amp;M)  404  specially designed to classify individual DSL lines. The interface between RM  402  and LQ&amp;M  404  supports the main RM with decisions on service subscription, resource allocation, service invocation, QoS monitoring and DSL fault localization and notification. LQ&amp;M  404 , which is responsible for a plurality of users, monitors each user&#39;s DSL link (in the DSL case) in terms of service quality, and reports that data to RM  402  in the Resource Management system situated at access edge site  406 . The data is then incorporated into service decisions. 
     In a communication, the LQ&amp;M  404  side runs web-services to which the client can connect at the RM side. This structure is used by RM  402  to request status data from the access network. In case LQ&amp;M  404  needs to pro-actively notify RM  402  about a changing status in the access network, a server in the RM  402  is ready to receive connections from the LQ&amp;M  404  client. 
       FIG. 5  is an exemplary high-level block diagram that illustrates a communication interface between the access network and the Resource Manager in accordance with an embodiment of the present invention. In the present invention, Resource Manager  502  and LQ&amp;M  504  act as either a server or a client, each function acting as a server, providing web services to the other. In order to communicate DSL line status (i.e., line ‘health’) towards Resource Manager  502 , a SOAP protocol (in this example) is used for implementing web services. Communication in both directions is required. Resource Manager  502  can always poll the LQ&amp;M  504  for line related status information (e.g., for QoS monitoring or during service provisioning). In this case, LQ&amp;M  504  hosts the server offering web-service to the Resource Manager, which acts as a client; and LQ&amp;M  504  may push urgent information (for example, line drops) to Resource Manager  502  to indicate a change in the access network. Resource Manager  502  acts as a server offering web services to LQ&amp;M  504 , which is acting as a client. 
       FIG. 6  depicts a high-level block diagram of the Resource Manager ( 602 ), web service-based interface ( 608 ), and LQ&amp;M ( 604 ,  606 ) in accordance with an embodiment of the present invention. LQ&amp;M server  604  sends queries via SNMP interface  609  to the actual Access Nodes in the DSL network (not shown) to learn about the current line state (scheduled monitoring). Performance and stability data is fetched from the access node in a scheduled way and stored for statistical analysis in database  610 . Several key performance indicators such as mean line rate, delay and stability-measures, are derived from the fetched source data utilizing an interpretation filter. The LQ&amp;M server interfaces with the DSL Network Management System (NMS) in order to fetch port addressing information along with line and end-user configurations and information. 
     RM  602  requests data from LQ&amp;M tool server  604  to learn about the access network state in case of admission control, policy or resource reservation decisions that have to be made. 
     During service delivery, LQ&amp;M tool server  604  automatically sends notifications to RM  602  about DSL status changes for fault notification, fault diagnoses and fault repair purposes. If LQ&amp;M tool server  604  identifies performance degradations on the DSL, RM  602  is informed so that re-prioritization and re-allocation of resources may be started. The interface  608  between RM  602  and LQ&amp;M tool server  604  can be implemented by any generic Remote Procedure Call (RPC) interface including a SOAP interface. 
     Each entity (RM and LQ&amp;M server) utilizes associated RPCs to handle the different message types listed in Table 1 below. LQ&amp;M tool server  604  contains definitions that allow RM  602  to send request messages, whereas RM  602  holds the means to handle notification messages initiated by LQ&amp;M tool server  604 . 
     Table 1 shows an overview of the types of messages utilized. For “last mile” monitoring and LQ&amp;M tool configuration request/response messages are defined. For last mile status changes, notifications are generated. 
     
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Message Overview 
               
             
          
           
               
                   
                 Response 
                 Flow 
               
               
                   
                   
               
             
          
           
               
                 Request 
                   
                   
               
               
                 Access Node Status Request 
                 Access Node Status Response 
                 RM            LQ&amp;M            RM 
               
               
                 DSL Resource Status Request 
                 DSL Resource Status Response 
                 RM            LQ&amp;M            RM 
               
               
                 ATM Resource Status Request 
                 ATM Resource Status Reply 
                 RM            LQ&amp;M            RM 
               
               
                 Threshold Update Request 
                 Threshold Update Response 
                 RM            LQ&amp;M            RM 
               
               
                 Threshold Retrieve Request 
                 Threshold Retrieve Response 
                 RM            LQ&amp;M            RM 
               
               
                 Notification 
               
               
                 LQ&amp;M Alive 
                 — 
                 LQ&amp;M            RM 
               
               
                 DSL Access Node Notification 
                 — 
                 LQ&amp;M            RM 
               
               
                 DSL Line Notification 
                 — 
                 LQ&amp;M            RM 
               
               
                 DSL Threshold Notification 
                 — 
                 LQ&amp;M            RM 
               
               
                   
               
             
          
         
       
     
     The following use cases outline the possible interaction between different entities during resource negotiation and service delivery, illustrating how the messages listed in Table 1 are used. 
     The first two use cases describe situations where the RM actively requests information about DSL line resources from LQ&amp;M in order to maintain admission control for service subscription and service invocation (request/response type of messages). The third use case shows a situation where LQ&amp;M pushes information about changes in the actual DSL performance of a user towards the resource manager to adapt the admission control scheme (notification type of messages). 
       FIG. 7  depicts a high-level diagram of message flow for Use Case  1  in accordance with an embodiment of the present invention. The first use case describes the circumstances when a user creates a new service subscription through a self-provisioning portal. The user browses to a self-provisioning portal to subscribe for a new service (IPTV). The portal displays the different available services together with their accompanying SLA descriptions. When the user initiates the service subscription procedure, a service request  702  is sent to the service manager at the service provider side to notify of the user subscription request. This initiates a procedure to check if enough resources are available to deliver the service according to the SLA (Resource Validation Request). This request towards RM is translated into a DSL Resource Status Request  704  towards LQ&amp;M that fetches the DSL status information via the SNMP interface. LQ&amp;M will parse this information into a DSL Resource Status Response  706 . 
     The DSL Resource Status Response message contains information of the total resource available on the DSL line. RM will use this information to update the network data model and cross-reference with existing service on the line to verify if the necessary resource are available to fulfill the SLA. The result of which will be return in the Service Subscription Reply to the end user. 
       FIG. 8  illustrates a message flow for Use Case  2  in accordance with an embodiment of the present invention. Use case  2  assumes that a service subscription already exists and that a user (residential, business user, network operator, service provider) wishes to invoice the service through the self-provisioning portal (note that the service invocation is not required to be initiated through the portal). 
     Service invocation  802  is issued to the service manager when the user selects the service to invoke from the portal. This will trigger Resource Validation Request  804  to RM, which in turn probes LQ&amp;M with ATM Resource Status Request  806 . LQ&amp;M will then read the ATM status information from the Internet Protocol Digital Subscriber Line Access Multiplexer (IPDSLAM) through the SNMP interface and send ATM Resource Status Response  808  to RM. 
     RM shall use the information in the response message in combination with the network data model and policy engine to determine availability of the requested resources. The result is sent to SM in the Resource Validation Reply, which then triggers an update of the self-provisioning portal. 
     During the invocation procedure the network resources are reserved; depending on the service type (unicast, multicast) and the user type (fixed, authenticated). 
       FIG. 9  depicts a high-level message flow diagram for Use Case  3  in accordance with an embodiment of the present invention. LQ&amp;M uses pre-configured threshold values to detect performance changes. If the LQ&amp;M function detects a change in line performance due to altered conditions on the line (noise, failures) the function will report (push) a status change (performance change) to the RM. With this information, RM can adapt its admission control scheme used for service invocation, update its network data model, and also notify the service manager about the change. A DSL Line Notification is followed by a DSL Resource Status Request message to retrieve the new line values. This may not have any effect on the current services running, but will influence the availability of new service session invocations. The DSL Line Notification  902  message is used to inform the RM on status change of an access node (access node up/down). The DSL Line Notification message provides line-specific changes (an access node supports several lines) such as a line activating or going down. 
     A DSL Threshold Notification message (not shown) is sent by the access node if a predetermined threshold on a performance parameter is crossed, this message is used to check whether conditions on a line have changed. The RM uses this information to recover the QoS and QoE to fulfill the applicable Service Level Agreement (SLA). 
     A simple example is that the RM (OAM function) is made aware that something is wrong with a line and services are dropped. This function can be used for fast and automatic trouble shooting and fault localization. 
     Available line resources are important to relay to the resource manager during the resource negotiation process of setting up a service. The resource manager may query LQ&amp;M to request the current line status of a particular PVC, port, and DSL access node. This information will be utilized by RM to apply necessary call admission control policies 
     Line values may change due to the nature of DSL, based on outside interference, cross-talk, etc. This may lead to service degradation if certain line values are reached. LQ&amp;M shall send a notification to RM when a specified attribute threshold is broken. The message can include the following information: access node id, port, PVC, VLAN, time, attribute and the new attribute value. 
     RM will apply appropriate policies on additional service that will be requested/activated based on the new line values. A notification from the LQ&amp;M will trigger an update in the network data model used by RM. 
     Once the Resource Manager has committed resources for a specific service flow a notification is sent to the LQ&amp;M function. The notification contains information on how to identify the service (access node identity and port) and parameter thresholds that will need to be monitored (i.e. SNR margins, CRC errors, bit rate, etc). This data will also define when to send line change notifications. 
     Current DSL line values may only be useful for short-term resource commitments. However, when creating a subscription or long-term resource reservations, such as for IPTV and VoIP usage, it may be important to take a historical view of DSL line stability. A line that experiences greater interference may not be suitable to deliver certain services, especially if the service provider wishes to provide service delivery guarantees. RM may contact LQ&amp;M to get historical statistical values on specific user line read from the access node. Since LQ&amp;M tracks performance/stability data from the access nodes and stores it in a database, it is possible to compute statistical performance indicators such as average rate and stability parameters. 
     A unified OAM and Resource Manager as described above provides a step towards a true e2e management system. Advantages include:
         Service Assurance: SLA guarantees and QoS is possible by that solution because the LQ&amp;M tools can monitor the actual service quality and compare with the agreed service layer agreement (SLA);   Dynamic Network View: The LQ&amp;M tool always has a fresh view of the network in terms of topology, line-state and performance. The RM can always learn about the network structure it needs to make a decision;   Monitoring, Notifications, Pro-active Alarms: LQ&amp;M enables automated and effective fault localization, fault diagnoses and fault repair mechanisms for DSL. This reduces OPEX costs due to line problems;   Nomadism on DSL: Since RM can query the LQ&amp;M tools anytime on the resource statues for lines, the proposed solution also enables Nomadism. The RM knows if services that a user subscribed to on his home-line are also working on visited-lines; and   Enables Self-Provisioning: Since the RM knows about the capacity and stability of lines, self-provisioning of services becomes possible (RM can decide if a service should be offered to a customer).       

     As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied over a wide range of applications. Accordingly, the scope of patented subject matter should not be limited to any of the specific exemplary teachings discussed above, but is instead defined by the following claims.