Internet Draft  AAA Framework for Multicasting  November 
                      2007 
                          
                          
                       
                                                                    Hiroaki Satou, NTT 
                         Internet Draft                              Hiroshi Ohta, NTT 
                         Expires: May 17,          Christian Jacquenet, France Telecom  
                         2008 
                                                                Tsunemasa Hayashi, NTT  
                                                          Haixiang He, Nortel Networks  
                                                                                       
                                                                     November 19, 2007 
                          
                          
                                    AAA Framework for Multicasting  
                             <draft-ietf-mboned-multiaaa-framework-05.txt> 
                          
                          
                      Status of this Memo 
                          
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                       Internet Draft  AAA Framework for Multicasting  November 
                      2007 
                          
                          
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                         This Internet-Draft will expire on May 17, 2008. 
                          
                          
                      Copyright Notice 
                          
                        Copyright (C) The IETF Trust (2007).  This document 
                         is subject to the rights, licenses and restrictions 
                         contained in BCP 78, and except as set forth therein, 
                         the authors retain all their rights. 
                          
                      Abstract 
                         IP multicast-based services, such as TV broadcasting 
                         or videoconferencing raise the issue of making sure 
                         that potential customers are fully entitled to 
                         access the corresponding contents. There is indeed a 
                         need for service and content providers to identify 
                         (if not authenticate, especially within the context 
                         of enforcing electronic payment schemes) and to 
                         invoice such customers in a reliable and efficient 
                         manner. This memo describes the framework for 
                         specifying the Authorization, Authentication and 
                         Accounting (AAA) capabilities that could be 
                         activated within the context of the deployment and 
                         the operation of IP multicast-based services.  This 
                         framework addresses the requirements presented in 
                         draft-ietf-mboned-maccnt-req-04.txt, "Requirements 
                         for Accounting, Authentication and Authorization in 
                         Well Managed IP Multicasting Services". The memo 
                         provides a basic AAA enabled model as well as an 
                         extended fully enabled model with resource and 
                         admission control coordination. 
                                                    
                          
                          
                          
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               STATUS OF THIS MEMO                                            1 
               COPYRIGHT NOTICE                                               2 
               ABSTRACT                                                       2 
               1. INTRODUCTION                                                5 
               1.1 PURPOSE AND BACKGROUND                                     5 
               2. DEFINITIONS AND ABBREVIATIONS                               6 
               2.1 DEFINITIONS                                                6 
               2.2 ABBREVIATIONS                                              7 
               3. COMMON USE MODELS AND NETWORK ARCHITECTURE IMPLICATIONS     7 
               4. FRAMEWORK AND ROLES OF ENTITIES                             8 
               4.1 FRAMEWORK FOR MULTICAST AAA                                8 
               4.1.1 MULTIPLE CPS ARE CONNECTED TO MULTIPLE NSPS              9 
               4.1.2 MULTIPLE CPS ARE CONNECTED TO A SINGLE NSP              10 
               4.1.3 A SINGLE CP IS CONNECTED TO MULTIPLE NSPS               11 
               4.1.4 A SINGLE CP IS CONNECTED TO SINGLE NSP                  11 
               4.2 USER ID                                                   11 
               4.2.1 CP-ASSIGNED USER ID                                     12 
               4.2.2 NSP-ASSIGNED USER ID                                    12 
               4.3 ACCOUNTING                                                12 
                   
                   
                   
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                Internet Draft  AAA Framework for Multicasting  November 2007 
                   
                   
               4.4 ACCESS CONTROL AND CP SELECTION BY NSP                    13 
               4.5 ADMISSION CONTROL INFORMATION BY NSP                      13 
               4.6 ACCESS CONTROL AND DISTINGUISHING OF USERS BY CP          14 
               4.7 AAA PROXY IN NSP                                          14 
               5.1 BASIC CONNECTION MODEL                                    14 
               5.2 CONSTITUENT LOGICAL FUNCTIONAL COMPONENTS OF THE FULLY 
               ENABLED AAA FRAMEWORK                                         15 
               5.3 MODULARITY OF THE FRAMEWORK                               19 
               6. IANA CONSIDERATIONS                                        19 
               7. SECURITY CONSIDERATIONS                                    19 
               8. CONCLUSION                                                 19 
               NORMATIVE REFERENCES                                          19 
               AUTHORS' ADDRESSES                                            20 
               COMMENTS                                                      20 
               FULL COPYRIGHT STATEMENT                                      21 
               COPYRIGHT (C) THE IETF TRUST (2007).                          21 
               INTELLECTUAL PROPERTY                                         21 
               EXPIRATION                                                    21 
               ACKNOWLEDGEMENT                                               22 
                   
                   
                   
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                Internet Draft  AAA Framework for Multicasting  November 2007 
                   
                   
                 
                1. Introduction 
                                                         
                1.1 Purpose and Background 
                  IP multicasting is designed to serve cases of group 
                  communication schemes of any kind, such as 1-to-n (case of 
                  TV broadcasting services for example) or n-to-p (case of 
                  videoconferencing services, for example).   
                     In these environments, IP multicast provides a better 
                  resource optimization than using a unicast transmission 
                  scheme, where data need to be replicated as many times as 
                  there are receivers. Activation of IP multicast 
                  capabilities in networks yields the establishment and the 
                  maintenance of multicast distribution trees that are 
                  receiver-initiated by nature: multicast-formatted data are 
                  forwarded to receivers who explicitly request them.  
                   
                       IP multicast-based services, such as TV broadcasting 
                  or videoconferencing raise the issue of making sure that 
                  potential customers are fully entitled to access the 
                  corresponding contents. 
                  There is indeed a need for service and content providers to 
                  identify (if not authenticate, especially within the 
                  context of enforcing electronic payment schemes) and to 
                  invoice such customers in a reliable and efficient manner.  
                  Solutions should consider a wide range of possible content 
                  delivery applications: content delivered over the multicast 
                  network may include video, audio, images, games, software 
                  and information such as financial data, etc. 
                   
                   
                        This memo describes a framework for specifying the 
                  Authorization, Authentication and Accounting (AAA) 
                  capabilities that could be activated within the context of 
                  the deployment and the operation of IP multicast-based 
                  services. This memo also describes a framework to realize 
                  high-quality multicast transport using a Resource and 
                  Admission Control System (RACS) with multicast 
                  Authorization. 
                  Specifically, this framework addresses the requirements 
                  presented in draft-ietf-mboned-maccnt-req-05.txt, 
                  "Requirements for Multicast AAA coordinated between Content 
                  Provider(s) and Network Service Provider(s)" MACCNT-REQ-
                  draft describes the requirements in CDN services using IP 
                  multicast[1]. The requirements are derived from: 
                       - need for user tracking and billing capabilities 
                       - need for network access control to satisfy the 
                  requirements of the Network Service Provider (NSP) and/or 
                  content access control to satisfy the requirements of the 
                  Content Provider (CP) 
                   
                   
                   
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                       - methods for sharing information between the network 
                  service provider and content provider to make it possible 
                  to fulfill the above two requirements. 
                   
                  Detailed requirements are presented in MACCNT-REQ-draft.   
                  These requirements include mechanisms for recording end-
                  user requests and provider responses for content-delivery, 
                  sharing user information (possibly anonymously depending on 
                  the trust model) between content provider and network 
                  service provider, and protecting resources through the 
                  prevention of network and content access by unauthorized 
                  users, as well as other AAA related requirements. 
                    
                  The purpose of this memo is to provide a generalized 
                  framework for  
                  specifying multicast-inferred AAA capabilities that can 
                  meet these requirements. This framework is to provide a 
                  basis for future work of investigating the applicability of 
                  existing AAA protocols to provide these AAA capabilities in 
                  IP multicast specific context and/or if deemed necessary, 
                  the refining or defining of protocols to provide these 
                  capabilities.   
                   
                   
                   
                2. Definitions and Abbreviations 
                   
                2.1 Definitions 
                   
                  For the purpose of this memo the following definitions 
                  apply: 
                   
                  Accounting: The set of capabilities that allow the 
                  retrieval of a set of statistical data that can be defined 
                  on a per customer and/or a per service basis, within the 
                  context of the deployment of multicast-based services. Such 
                  data are retrieved for billing purposes, and can be 
                  retrieved on a regular basis or upon unsolicited requests. 
                  Such data include (but are not necessarily limited to) the 
                  volume of multicast-formatted data that have been forwarded 
                  to the receiver over a given period of time, the volume of 
                  multicast-formatted data that have been exchanged between a 
                  receiver (or set of) and a given source over a given period 
                  of time (e.g. the duration of a multicast session), etc.  
                   
                  Authentication: action for identifying a user as a genuine 
                  one. 
                
                  Authorization: The set of capabilities that need to be 
                  activated to make sure a given requesting customer is (1) 
                   
                   
                   
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                  what he claims to be (identification purposes), and (2) is 
                  fully entitled to access a set of services (authentication 
                  purposes). 
                   
                  Receiver: an end-host or end-client which receives content.  
                  A receiver may be identified by a network ID such as MAC 
                  address or IP address.   
                   
                  User: a human with a user account.  A user may possibly use 
                  multiple reception devices.  Multiple users may use the 
                  same reception device. 
                   
                  Note: The definition of a receiver (device) and a user 
                  (human) should not be confused. 
                
                   
                2.2 Abbreviations 
                 
                  For the purpose of this draft the following abbreviations 
                  apply: 
                   
                  ACL: Access Control List 
                   
                  AN: Access Node  
                   
                  CAPCF: Conditional Access Policy Control Function 
                   
                  CDN: Content Delivery Network 
                   
                  CDS: Content Delivery Services 
                   
                  CP: Content Provider 
                   
                  CPE: Customer Premise Equipment 
                   
                  MACF: Multicast Admission Control Function  
                   
                  NSP: Network Service Provider 
                   
                  TS: Transport System 
                   
                3. Common use models and network architecture implications 
                   
                  In some cases a single entity may design and be responsible 
                  for a system that covers the various common high-level 
                  requirements of a multicasting system such as 1) content 
                  serving, 2) the infrastructure to multicast it, 3) network 
                  and content access control mechanisms. In many cases 
                  however the content provision and network provision roles 
                  are divided between separate entities.  The MACCNT-REQ-
                   
                   
                   
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                  draft provides more detail of the multiple versus single 
                  entity CDS network models. 
                
                  As such it should not be assumed that the entity 
                  responsible for the multicasting structure and the entity 
                  responsible for content serving are the same.  Indeed 
                  because the infrastructure for multicasting is expensive 
                  and many content holders are not likely to be competent at 
                  building and maintaining complicated infrastructures 
                  necessary for multicasting, many content holders would 
                  prefer to purchase transport and management services from a 
                  network service provider and thus share the infrastructure 
                  costs with other content holders.   
                   
                  Similarly network service providers in many cases do not 
                  specialize in providing content and are unlikely to build 
                  and maintain such a resource-intensive system without a 
                  certain level of demand from content holders.   
                   
                  The use model of a single NSP providing multicasting 
                  services to multiple CPs the following general requirements 
                  from MACCNT-REQ-draft apply: 
                   
                       -Need for user tracking and billing capabilities 
                       -Need for QoS control such as resource management and 
                  admission control 
                       -Need for conditional content access control 
                  satisfactory to the requirements of the CP 
                       -Methods for sharing information between the NSP and 
                  CP to make the above two possible 
                        
                    
                  When the NSP and CP are the same single entity the general 
                  requirements are as follows. 
                   
                       -Need for user tracking and user-billing capabilities 
                       -Need for access control and/or content protection at 
                  level the entity deems appropriate 
                        
                   
                 
                4. Framework and Roles of Entities4.1 Framework for multicast 
                   AAA  
                
                  A general high-level framework can be represented as 
                  follows.  
                            
                           +------------------------------+ 
                           |    user                      | 
                           |                              | 
                   
                   
                   
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                           +------------------------------+ 
                               | Access       ^ Response 
                               | Request      |  
                               V              | 
                           +------------------------------+ 
                           |    NSP                       | 
                           |                              | 
                           +------------------------------+ 
                               | Access         ^ Response 
                               | Request        | (Success) 
                               v                | 
                           +------------------------------+ 
                           |    CP                        | 
                           |                              | 
                           +------------------------------+ 
                                       Figure 1 
                
                
                  For the sake of simplicity, the above diagram portrays a 
                  case where there is a single NSP entity and a single CP 
                  entity, but multiple CPs can be connected to a single NSP 
                  (e.g. NSP may provide connections to multiple CPs to 
                  provide a wide selection of content categories.) It is also 
                  possible for a single CP to be connected to multiple NSP 
                  networks (e.g. network selection). Furthermore it is 
                  possible that the NSP and CP could be the same entity. A 
                  NSP and CP authenticate and authorize each other when they 
                  establish connectivity. Below the general case of multiple 
                  NSPs with multiple CPs is explained.  Then, the various 
                  combinations of single and multiple CPs and NSPs are 
                  described in relation to the general case. 
                   
                4.1.1 Multiple CPs are connected to multiple NSPs 
                   
                  The user subscribes to multiple NSPs and multiple CPs in 
                  this usage case.  The user selects a CP and a NSP when the 
                  user requests content. The NSP may be automatically 
                  selected by a user terminal: e.g. a fixed line NSP by a set 
                  top box or a mobile NSP by a mobile phone.  In some usage 
                  cases it is possible that the NSP used by a certain user 
                  will not always be the same.  For example a user may have 
                  contracted with more than one NSP: one for fixed line 
                  access and another for mobile roaming access.  
                   
                  The content may be associated with (or managed by) a 
                  specific CP. In this case, when the user selects content, 
                  the CP is automatically selected.  
                   
                  The user should send an Access-Request to the selected NSP 
                  with enough information not only for authentication by the 
                   
                   
                   
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                  CP but also for CP selection and admission control by the 
                  NSP. 
                   
                  When an NSP receives an Access-Request from a user, the NSP 
                  selects the appropriate CP for the received Access-Request 
                  and relays the content request. As the NSP is responsible 
                  for managing its network resources, the NSP may perform 
                  admission control.The NSP will allow access to the network 
                  and contents conditional to both the CP's content 
                  authorization result and the NSPs network availability.  
                  That is, the NSP starts multicast flow only when it has 
                  both 1) received an ‘‘accept’’ response from the CP and 2) 
                  determined that the network resources (e.g. bandwidth) are 
                  sufficient to serve the multicast channel. When neither of 
                  these conditions are met, the NSP does not start the 
                  requested multicast channel. When the NSP already knows 
                  that network resources are insufficient or there is a 
                  network failure, the NSP may choose to not relay the 
                  Access-Request to the CP. The NSP is also responsible for 
                  relaying the Response message from the CP to the user 
                  whether the user is eligible to receive content (in 
                  response to the corresponding Access-Request from the user 
                  to the CP.) In cases that the NSP does not start multicast 
                  because of its own network issues (e.g. lack of network 
                  resources or network failure), the NSP notifies the user 
                  with a reason for rejecting the request. 
                   
                  A CP receives an Access-Request relayed by the NSP. The CP 
                  authenticates the NSP’s identity and makes an authorization 
                  decision regarding the NSP’s eligibility to provide users 
                  access to its contents.  The CP is responsible for 
                  Authentication and Authorization of users' access to 
                  content that the CP manages. The CP hopes to collect 
                  accounting information related to the access of their 
                  content. The CP responds to the NSP regarding the relayed 
                  Access-Request.  When the CP cannot (e.g. error or 
                  resource issues) or decides not (e.g. policy issues) to 
                  deliver content, the CP is responsible for notifying the 
                  NSP of the reason.  It is up to the NSP how to relay or 
                  translate the reasons for rejection to the user. 
                
                4.1.2 Multiple CPs are connected to a single NSP 
                   
                  The user subscribes to a single NSP which provides 
                  multicasting of channels from multiple CPs in this usage 
                  case. In this case the user does not select an NSP.  The 
                  user selects a CP when the user requests content. The 
                  content may be associated with (or managed by) the specific 
                  CP, when the user selects content, the CP is automatically 
                  selected.  
                   
                   
                   
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                  The user should send an Access-Request to the specific NSP 
                  with enough information not only for authentication by the 
                  CP but also for CP selection and admission control by the 
                  NSP. 
                   
                  The role of the NSP is the same as that described in 4.1.1. 
                   
                  The role of a CP is the same as that described in 4.1.1. 
                   
                4.1.3 A single CP is connected to multiple NSPs 
                   
                   A user subscribes to multiple NSPs but a single CP in this 
                  usage case.  A user selects the NSP when the user requests 
                  content but the CP is fixed.  The user should send an 
                  Access-Request to the selected NSP with enough information 
                  not only for authentication by the CP but also for 
                  admission control by the NSP. 
                   
                  The role of the NSP is similar to the description in 4.1.1, 
                  with the exception that when a NSP receives an Access-
                  Request from a user, NSP relays it to the CP without CP 
                  selection. 
                   
                  The role of the CP is the same as that described in 4.1.1.  
                      
                 4.1.4 A single CP is connected to single NSP 
                   
                      In this case, a user subscribes to only one NSP and one 
                  CP. The user does not select NSP and CP in this scenario. 
                  The user should send an Access-Request to the NSP with 
                  enough information not only for authentication by the CP 
                  but also for admission control by the NSP. 
                       
                      The role for the NSP is the same as 4.1.3 
                  The role of the CP is the same as the description in 4.1.1.  
                   
                  The NSP and CP could be the same entity. In this case, the 
                  roles of the NSP and CP may be combined. 
                   
                
                4.2 User ID 
                   
                  Users may hold multiple user IDs: IDs which have been 
                  separately assigned for each subscription they may have for 
                  various NSPs and CPs.  The NSPs and CPs manage the user IDs 
                  for their respective domains. A CP identifies a user by a 
                  user ID assigned by CP itself. A NSP identifies a user by a 
                  user ID assigned by NSP itself. The user IDs are only 
                  meaningful in the context of each domain. Users may hold 
                  multiple user IDs which have been separately assigned for 
                   
                   
                   
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                  each subscription they may have for various NSPs and CPs. 
                   
                4.2.1 CP-assigned user ID 
                   
                  CPs assign user IDs to their users. The user may have more 
                  than one CP-assigned user ID per a specific CP.  A user 
                  sends an Access-Request to a NSP, the CP-assigned user ID 
                  should be indicated so that the CP can identify the user 
                  requesting content access.  A NSP should relay the CP-
                  assigned user ID from the user to the CP. A NSP should not 
                  send a CP-assigned user ID to any CP except the one which 
                  assigned it and should not relay it all if there is no 
                  appropriate CP that assigned the user ID. 
                
                4.2.2 NSP-assigned user ID 
                   
                  NSPs assign user IDs to their users. A user may have more 
                  than one NSP-assigned user ID per a specific NSP.  A user 
                  sends an Access-Request to a NSP, the NSP-assigned user ID 
                  may be indicated in it so that the NSP can identify the 
                  user. The NSP should not relay the NSP-assigned user ID to 
                  the CP for security reasons. The NSP may identify the 
                  multicast-access user by other methods than the NSP-
                  assigned userID, e.g. by the access port. 
                   
                  The actual mapping rules for NSP-assigned user IDs with CP-
                  user assigned IDs in account logs is a matter for the 
                  providers and out of the scope of this framework.  
                   
                4.3 Accounting 
                   
                  There are some specific accounting issues for multicasting.  
                  A (S,G) should be recorded as a channel identifier. The 
                  last hop devices, such as a IGMP or MLD router and a IGMP 
                  or MLD proxy, notify a (S,G) to AAA function in the NSP. 
                  The (S,G) information should be notified to the CP as part 
                  of the accounting log. 
                   
                  A NSP records accounting start corresponding to only the 
                  first Join for a specific user access session. A NSP should 
                  not treat a Query-responded Join as the accounting start. 
                   
                  A NSP records accounting stop triggered by not only user 
                  requested Leave but also timeout of a multicast state or 
                  re-authentication failure. A NSP may also record an 
                  accounting stop due to network availability reasons such as 
                  failure. The NSP logs the reason for each accounting stop.  
                   
                   
                   
                   
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                  Also, intermittent logs between the join and leave would 
                  allow for finer diagnostics and therefore could serve 
                  useful in billing discrepancies, and provide for a finer 
                  estimation of the time spent for delivering the content in 
                  the event that users disconnect without sending leave 
                  messages.  
                   
                   
                
                4.4 Access Control and CP selection by NSP 
                   
                  When a NSP receives an access request from a user, the NSP 
                  determines to which CP the request is to be directed.  The 
                  NSP may select a CP based on CP-assigned userID with CP 
                  domain name or channel identifier (S,G). The user should 
                  include in the request sufficient information for CP 
                  selection. 
                
                
                4.5 Admission Control Information by NSP 
                
                  After authorizing a user request, the NSP may have further 
                  conditions for determining its admission control decision.  
                   
                  The NSP needs to know traffic parameters of a multicast 
                  channel for admission control. The traffic parameter 
                  information may be either indicated by the user or CP 
                  within the access request and responses, or otherwise 
                  shared between the NSP and CP outside the access-request 
                  message mechanism:   
                       - A user may declare traffic parameters for each 
                  Access-Request.  
                       - A CP may notify a mapping between the channel 
                  identifier (S,G) and traffic parameters in the Response 
                  message when the CP authorizes an access request. 
                       - The NSP may maintain a mapping between channel 
                  identifier (S,G) and traffic parameters in advance, for 
                  example pre-configured by agreement between the CP and NSP 
                  on a per channel basis.  
                   
                  A NSPs admission control may manage integrated network 
                  resources for unicast usage, such as VoIP or unicast 
                  streaming, and multicast usage. Alternatively, it may 
                  manage network resources separately for unicast and 
                  multicast usage. In either case, AAA and admission control 
                  framework for multicast usage is independent of unicast 
                  admission control. 
                   
                   
                   
                   
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                  Such QoS measurement and policy mechanisms themselves 
                  depend on NSP policies and are out of the scope of this 
                  memo.  
                
                4.6 Access Control and Distinguishing of Users by CP 
                   
                  The user ID and authentication information are forwarded 
                  transparently by the NSP so that the CP can distinguish the 
                  user, as well as authenticate and authorize the request. 
                   
                4.7 AAA proxy in NSP 
                   
                  A NSP may act as AAA proxy of a CP based upon an agreement 
                  between the NSP and the CP.  The AAA proxy would store 
                  information about permissions of a specific user to receive 
                  multicast data from specified channel(s) up to specified 
                  expiration date(s) and time(s).   
                  If such proxying is implemented, the NSP may receive 
                  authorization conditions from a CP in advance and 
                  statically hold them, or a CP may send them dynamically in 
                  the Response message.  The user has permission to receive 
                  multicast channel at that time. The NSP starts the 
                  multicasting without querying the CP.   
                   
                  The CP may send unsolicited requests to the NSP to refresh 
                  or change the permissions for a user for specific 
                  channel(s).   
                   
                  When a user is receiving multicast content and the 
                  permission is about to expire, the NSP may send a 
                  notification to the user client that his session is about 
                  to expire, and that he will need to reauthenticate. In such 
                  a case, the user will have to send the Access-Request.  In 
                  the case that the user still has permission to the content, 
                  they should be able to continue to receive the content 
                  without interruption.  
                  When re-authentication fails, the NSP should stop the 
                  multicast channel and record accounting stop. 
                   
                  5. Network Connection Model and Functional Components 
                   
                  Section 3.1 introduces the high-level AAA framework for 
                  multicasting.  This section provides more details on the 
                  network connection model and constituent functional 
                  components.  
                
               5.1 Basic Connection Model 
                   
                  In the simple case represented in Figure 1 the NSP is the 
                  sole entity providing network resources including network 
                   
                   
                   
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                  access to the User.  First a user that requests content 
                  sends an Access request to an NSP which then forwards it on 
                  to the appropriate CP for Authentication and Authorization 
                  purposes. The CP responds with either "success" or 
                  "failure".  If "success", the NSP may forward a success 
                  response and stream multicast data to the user. 
                   
                  In this model the user selects the NSP to which to send its 
                  content request. Based on this request the NSP selects an 
                  appropriate CP to which it forwards the request. The CP 
                  responds to the NSP's request: it may not respond to 
                  another NSP in regards to the request. 
                   
                  In this model, as described in section 3.1, the 
                  relationship between NSP and CP can be 1:1, 1:N or M:N.  
                  Users may connect to multiple networks, and networks have 
                  multiple users.   
                   
               5.2 Constituent Logical Functional Components of the fully 
               enabled AAA Framework 
                   
                  Requirements for "fully AAA and QoS enabled" IP 
                  multicasting networks were defined in MACCNT-REQ-draft. To 
                  allow for levels of enablement, this memo defines two 
                  models within the framework: "AAA enabled" multicasting and  
                  "Fully enabled AAA" multicasting which means "AAA enabled" 
                  with added admission control functions. 
                   
                  Section 3.1 introduces the high-level AAA framework for 
                  multicasting.  Below is a diagram of a AAA enabled 
                  multicasting network with AAA, including the logical 
                  components within the various entities.   
                   
                   
                  AAA enabled framework (basic model) 
                           +-------------------------------+ 
                           | user                          | 
                           |+- - - - - - - - - - - - - - -+| 
                           || CPE                         || 
                           ||                             || 
                           |+- - - - - | - - - - - - - - -+| 
                           +-----------|-------------------+ 
                                       | 
                                -------|------ IFa 
                                       |  
                           +-----------|-------------------+ 
                           | NSP       |                   | 
                           |+- - - - - |- -_+              | 
                           ||TS        |    |              | 
                           |    +------|-+                 | 
                   
                   
                   
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                              ||   | AN     |  |              | 
                           |    |        |                 | 
                           ||   +------|-+  |              | 
                           |           |     IFb           | 
                           ||   +------|-+  | | +---------+| 
                           |    |        |----|-|mAAA     || 
                           ||   | NAS    |  | | |(MACF *) || * optional 
                           |    +--------+      +---------+| 
                           ||+- - - - - - - +      |       | 
                           +-----------------------|--------+  
                                                   | 
                                            -------|------ IFc 
                                                   |  
                           +-----------------------|-------+ 
                           | CP               +---------+  | 
                           |                  |  CP-AAA |  | 
                           |                  +---------+  | 
                           +-------------------------------+ 
                                   Figure 2 
                   
                   
                  The user entity includes the CPE (Customer Premise 
                  Equipment) which includes the user host(s) and optionally a 
                  multicast proxy (not shown in the Figure 2.)   
                   
                  The NSP (Network Service Provider) in the basic model 
                  includes the transport system and a logical element for 
                  multicast AAA functionality.  The transport system is 
                  comprised of the access node and NAS (network access 
                  server) An AN may be connected directly to mAAA or a NAS 
                  relays AAA information between an AN and a mAAA 
                  Descriptions of AN and its interfaces are out of scope for 
                  this memo.  The multicast AAA function may be provided by a 
                  multicast AAA server (mAAA) which may include the function 
                  by which the access policy is downloaded to the NAS 
                  (Multicast access control function.) The interface between 
                  mAAA and the NAS is labeled IFb in Figure 2. Over IFb the 
                  NAS makes an access request to the NSP-mAAA and the mAAA 
                  replies. The mAAA may push conditional access policy to the 
                  NAS. 
                   
                  The content provider may have its own AAA server which has 
                  the authority over access policy for its contents. 
                   
                  The interface between the user and the NSP is labeled IFa 
                  in Figure 2.  Over IFa the user makes a multicasting 
                  request to the NSP.  The NSP may in reply send multicast 
                  traffic depending on the NSP and CP’s policy decisions. 
                   
                   
                   
                   
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                  The interface between the NSP and CP is labeled IFc. Over 
                  IFc the NSP requests to the CP-AAA for access to contents 
                  and the CP replies.  CP may also send conditional access 
                  policy over this interface within the context of proxying 
                  multicast AAA messagescaching. 
                   
                   
                   
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                       Fully enabled framework  
                           +-------------------------------+ 
                           | user                          | 
                           |+- - - - - - - - - - - - - - -+| 
                           || CPE                         || 
                           ||                             || 
                           |+- - - - - | - - - - - - - - -+| 
                           +-----------|-------------------+ 
                                       | 
                                -------|------ IFa 
                                       |  
                           +-----------|-----------------------+ 
                           |+- - - - - |- - _+   + - - - - - + | 
                           ||TS        |   | |   |           | | 
                           |    +------|-+ |       +--------+  | 
                           ||   | AN     | | |   | | MACF  || | 
                           |    |        | |       |        |  | 
                           ||   +------|-+ | |   | +---|----+| | 
                           |           |   |           |    |  | 
                           |           |   | |     IFd----- |  | 
                           |           |   |  IFb      |    |  | 
                           ||   +------|---+ | | | +---|----+| | 
                           |    |          |---|---| mAAA   |  | 
                           ||   | NAS      | | | | |(MACF *)|| | * optional 
                           |    +----------+ |     +--------+  | 
                           ||+- - - - - - - -+ - - |- - - - -+ | 
                           +-----------------------|-----------+  
                                                   | 
                                            -------|------ IFc 
                                                   |  
                           +-----------------------|-------+ 
                           | CP               +---------+  | 
                           |                  |  CP-AAA |  | 
                           |                  +---------+  | 
                            +-------------------------------+ 
                                          Figure 3 
                
                   
                  In the fully enabled model the NSP also includes a 
                  component that provides network resource management (e.g. 
                  QoS management), as described in section 3.4, "Network 
                  Resource Management by NSP".  In the fully enabled model 
                  (Figure 3) resource management and admission control is 
                  provided by MACF (multicast admission control function). 
                  Before replying to the user's multicast request the mAAA 
                  queries the MACF for a network resource access decision 
                  over the interface IFd.   The MACF is responsible for 
                  allocating network resources for multicast traffic.  To 
                  provide MACF with the relevant network resource 
                   
                   
                   
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                  availability information, NAS notifies MACF via mAAA that 
                  sending multicast traffic has ceased.  
                 
                5.3 Modularity of the framework 
                   
                  In the interest of flexibility, this framework is modular 
                  so that it is possible that partially enabled versions of 
                  the models are supported. An AAA-enabled version provides 
                  AAA functionality without Network Resource management.  A 
                  Network-Resource-Management-enabled (QoS-enabled) version 
                  provides Network Resource management without AAA 
                  functionality.  Similarly, the possibility of one or more 
                  layers of transit provision between an NSP and CP is in the 
                  interest of modularity and extendibility. 
                   
                   
                6. IANA considerations 
                   
                  This memo does not raise any IANA consideration issues. 
                   
                   
                7. Security considerations 
                   
                  Refer to section 3.3.  Also the user information related to 
                  authentication with the CP must be protected in some way.  
                  Otherwise, this memo does not raise any new security issues 
                  which are not already addressed by the original protocols.  
                  Enhancement of multicast access control capabilities should 
                  enhance security performance. 
                   
                   
                8. Conclusion 
                   
                  This memo provides a generalized framework for solution 
                  standards to meet the requirements.  Further work should be 
                  done to specify the interfaces between the user and NSP, 
                  NAS and mAAA, mAAA and MACF and NSP-mAAA and CP-AAA 
                  (presented in 5.2.) 
                   
                   
                Normative References 
                   
                  [1] Hayashi, et. al., Requirements for Multicast AAA 
                       coordinated between Content Provider(s) and Network 
                       Service Provider(s)", draft-ietf-mboned-maccnt-req-
                       05.txt, September 2007, Work in Progress. 
                   
                  [2] RFC-3810, Vida, R. and L. Costa, "Multicast Listener 
                       Discovery Version 2 (MLDv2) for IPv6", June 2004.  
                   
                   
                   
                   
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                  [3] RFC-3376, Cain B., et.al., "Internet Group Management 
                       Protocol, Version 3", October 2002.  
                   
                   
               Authors' Addresses 
                   
                          Hiroaki Satou 
                          NTT Network Service Systems Laboratories 
                          3-9-11 Midoricho, Musashino-shi, Tokyo, 180-8585 
                  Japan 
                          Phone : +81 422 59 4683 
                          Email : satou.hiroaki@lab.ntt.co.jp 
                   
                          Hiroshi Ohta 
                          NTT Network Service Systems Laboratories 
                          3-9-11 Midoricho, Musashino-shi, Tokyo, 180-8585 
                  Japan 
                                  Phone : +81 422 59 3617 
                          Email: ohta.hiroshi@lab.ntt.co.jp 
                
                          Christian Jacquenet 
                          France Telecom R&D 
                          4, rue du Clos Courtel -
                                                 - BP 91226 
                          35512 Cesson-SévignECedex, France 
                          Phone: +33 2 99 12 49 40 
                          Email: christian.jacquenet@orange-ftgroup.com  
                   
                          Tsunemasa Hayashi 
                          NTT Network Innovation Laboratories 
                          1-1 Hikari-no-oka, Yokosuka-shi, Kanagawa, 239-0847 
                  Japan 
                          Phone: +81 46 859 8790 
                          Email: tsunemasa@gmail.com 
                   
                          Haixiang He 
                          Nortel 
                          600 Technology Park Drive 
                          Billerica, MA 01801, USA 
                          Phone: +1 978 288 7482 
                          Email: haixiang@nortel.com 
                   
                   
                Comments 
                   
                  Comments are solicited and should be addressed to the 
                  mboned working group's mailing list at 
                  mboned@lists.uoregon.edu_and/or the authors.
                   
                   
                   
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                Full Copyright Statement 
                   
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                  This Internet-Draft will expire on May 17, 2008. 
                   
                   
                   
                   
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                Acknowledgement 
                   
                  Funding for the RFC Editor function is currently provided 
                  by the Internet Society. 
                   
                   
                   
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