--- 1/draft-ietf-mboned-interdomain-peering-bcp-08.txt 2017-07-17 13:13:11.281164145 -0700 +++ 2/draft-ietf-mboned-interdomain-peering-bcp-09.txt 2017-07-17 13:13:11.333165401 -0700 @@ -1,57 +1,56 @@ MBONED Working Group Percy S. Tarapore Internet Draft Robert Sayko Intended status: BCP AT&T -Expires: August 2, 2017 Greg Shepherd - Toerless Eckert +Expires: January 17, 2018 Greg Shepherd Cisco + Toerless Eckert + Futurewei Technologies Ram Krishnan SupportVectors - February 2, 2017 + July 17, 2017 Use of Multicast Across Inter-Domain Peering Points - draft-ietf-mboned-interdomain-peering-bcp-08.txt + draft-ietf-mboned-interdomain-peering-bcp-09.txt Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on August 2, 2017. + This Internet-Draft will expire on January 17, 2018. Copyright Notice Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other @@ -61,93 +60,88 @@ This document examines the use of Source Specific Multicast (SSM) across inter-domain peering points for a specified set of deployment scenarios. The objective is to describe the setup process for multicast-based delivery across administrative domains for these scenarios and document supporting functionality to enable this process. Table of Contents - 1. Introduction...................................................3 - 2. Overview of Inter-domain Multicast Application Transport.......4 - 3. Inter-domain Peering Point Requirements for Multicast..........6 - 3.1. Native Multicast..........................................6 - 3.2. Peering Point Enabled with GRE Tunnel.....................8 + 1. Introduction .................................................. 3 + 2. Overview of Inter-domain Multicast Application Transport ...... 4 + 3. Inter-domain Peering Point Requirements for Multicast ......... 6 + 3.1. Native Multicast ......................................... 6 + 3.2. Peering Point Enabled with GRE Tunnel .................... 8 3.3. Peering Point Enabled with an AMT - Both Domains Multicast - Enabled........................................................9 + Enabled ....................................................... 9 3.4. Peering Point Enabled with an AMT - AD-2 Not Multicast - Enabled.......................................................10 + Enabled ...................................................... 10 3.5. AD-2 Not Multicast Enabled - Multiple AMT Tunnels Through - AD-2..........................................................12 - 4. Supporting Functionality......................................14 + AD-2 ......................................................... 12 + 4. Supporting Functionality ..................................... 14 4.1. Network Interconnection Transport and Security Guidelines15 - 4.2. Routing Aspects and Related Guidelines...................15 - 4.2.1 Native Multicast Routing Aspects..................16 - 4.2.2 GRE Tunnel over Interconnecting Peering Point.....17 - 4.2.3 Routing Aspects with AMT Tunnels.....................17 + 4.2. Routing Aspects and Related Guidelines .................. 15 + 4.2.1 Native Multicast Routing Aspects ................. 16 + 4.2.2 GRE Tunnel over Interconnecting Peering Point .... 17 + 4.2.3 Routing Aspects with AMT Tunnels .................... 17 4.3. Back Office Functions - Provisioning and Logging Guidelines - ..............................................................20 - 4.3.1 Provisioning Guidelines...........................20 - 4.3.2 Application Accounting Guidelines.................21 - 4.3.3 Log Management Guidelines.........................22 + ............................................................. 20 + 4.3.1 Provisioning Guidelines .......................... 20 + 4.3.2 Application Accounting Guidelines ................ 21 + 4.3.3 Log Management Guidelines ........................ 22 4.4. Operations - Service Performance and Monitoring Guidelines22 - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - - 4.5. Client Reliability Models/Service Assurance Guidelines...25 - 5. Troubleshooting and Diagnostics...............................25 - 6. Security Considerations.......................................26 - 7. IANA Considerations...........................................27 - 8. Conclusions...................................................27 - 9. References....................................................27 - 9.1. Normative References.....................................27 - 9.2. Informative References...................................28 - 10. Acknowledgments..............................................29 + 4.5. Client Reliability Models/Service Assurance Guidelines .. 25 + 5. Troubleshooting and Diagnostics .............................. 25 + 6. Security Considerations ...................................... 26 + 7. IANA Considerations .......................................... 27 + 8. Conclusions .................................................. 27 + 9. References ................................................... 27 + 9.1. Normative References .................................... 27 + 9.2. Informative References .................................. 28 + 10. Acknowledgments ............................................. 28 1. Introduction Content and data from several types of applications (e.g., live video streaming, software downloads) are well suited for delivery via multicast means. The use of multicast for delivering such content/data offers significant savings for utilization of resources in any given administrative domain. End user demand for such content/data is growing. Often, this requires transporting the content/data across administrative domains via inter-domain peering points. The objective of this Best Current Practices document is twofold: o Describe the technical process and establish guidelines for setting up multicast-based delivery of application content/data across inter-domain peering points via a set of use cases. o Catalog all required information exchange between the - administrative domains to support multicast-based delivery. This - enables operators to initiate necessary processes to support - inter-domain peering with multicast. + administrative domains to support multicast-based delivery. + This enables operators to initiate necessary processes to + support inter-domain peering with multicast. The scope and assumptions for this document are stated as follows: o For the purpose of this document, the term "peering point" refers to an interface between two networks/administrative domains over which traffic is exchanged between them. A Network-Network Interface (NNI) is an example of a peering point. o Administrative Domain 1 (AD-1) is enabled with native multicast. A peering point exists between AD-1 and AD-2. o It is understood that several protocols are available for this purpose including PIM-SM [RFC4609], Protocol Independent Multicast - Source Specific Multicast (PIM-SSM) [RFC7761], Internet Group Management Protocol (IGMP) [RFC3376], and Multicast Listener Discovery (MLD) [RFC3810]. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - o As described in Section 2, the source IP address of the multicast stream in the originating AD (AD-1) is known. Under this condition, PIM-SSM use is beneficial as it allows the receiver's upstream router to directly send a JOIN message to the source without the need of invoking an intermediate Rendezvous Point (RP). Use of SSM also presents an improved threat mitigation profile against attack, as described in [RFC4609]. Hence, in the case of inter-domain peering, it is recommended to use only SSM protocols; the setup of inter- domain peering for ASM (Any-Source Multicast) is not in scope @@ -178,22 +172,20 @@ between many operators, is not in scope for this document. This document also attempts to identify ways by which the peering process can be improved. Development of new methods for improvement is beyond the scope of this document. 2. Overview of Inter-domain Multicast Application Transport A multicast-based application delivery scenario is as follows: -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - o Two independent administrative domains are interconnected via a peering point. o The peering point is either multicast enabled (end-to-end native multicast across the two domains) or it is connected by one of two possible tunnel types: o A Generic Routing Encapsulation (GRE) Tunnel [RFC2784] allowing multicast tunneling across the peering point, or o An Automatic Multicast Tunnel (AMT) [RFC7450]. o A service provider controls one or more application sources in AD-1 which will send multicast IP packets for one or more @@ -218,22 +210,20 @@ Enterprise case. The Use Cases describing various architectural configurations for the multicast distribution along with associated requirements is described in section 3. Unique aspects related to the Enterprise network possibility will be described in this section. A comprehensive list of pertinent information that needs to be exchanged between the two domains to support various functions enabling the application transport is provided in section 4. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - 3. Inter-domain Peering Point Requirements for Multicast The transport of applications using multicast requires that the inter-domain peering point is enabled to support such a process. There are five Use Cases for consideration in this document. 3.1. Native Multicast This Use Case involves end-to-end Native Multicast between the two administrative domains and the peering point is also native @@ -262,87 +252,84 @@ Advantages of this configuration are: o Most efficient use of bandwidth in both domains. o Fewer devices in the path traversed by the multicast stream when compared to unicast transmissions. From the perspective of AD-1, the one disadvantage associated with native multicast into AD-2 instead of individual unicast to every EU - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - in AD-2 is that it does not have the ability to count the number of End Users as well as the transmitted bytes delivered to them. This information is relevant from the perspective of customer billing and operational logs. It is assumed that such data will be collected by the application layer. The application layer mechanisms for generating this information need to be robust enough such that all pertinent requirements for the source provider and the AD operator are satisfactorily met. The specifics of these methods are beyond the scope of this document. Architectural guidelines for this configuration are as follows: - a. Dual homing for peering points between domains is recommended as - a way to ensure reliability with full BGP table visibility. + a. Dual homing for peering points between domains is recommended + as a way to ensure reliability with full BGP table visibility. - b. If the peering point between AD-1 and AD-2 is a controlled network - environment, then bandwidth can be allocated accordingly by the - two domains to permit the transit of non-rate adaptive multicast - traffic. If this is not the case, then it is recommended that the - multicast traffic should support rate-adaption. + b. If the peering point between AD-1 and AD-2 is a controlled + network environment, then bandwidth can be allocated + accordingly by the two domains to permit the transit of non- + rate adaptive multicast traffic. If this is not the case, then + it is recommended that the multicast traffic should support + rate-adaption. - c. The sending and receiving of multicast traffic between two domains - is typically determined by local policies associated with each - domain. For example, if AD-1 is a service provider and AD-2 is an - enterprise, then AD-1 may support local policies for traffic - delivery to, but not traffic reception from AD-2. Another example - is the use of a policy by which AD-1 delivers specified content - to AD-2 only if such delivery has been accepted by contract. + c. The sending and receiving of multicast traffic between two + domains is typically determined by local policies associated + with each domain. For example, if AD-1 is a service provider + and AD-2 is an enterprise, then AD-1 may support local policies + for traffic delivery to, but not traffic reception from AD-2. + Another example is the use of a policy by which AD-1 delivers + specified content to AD-2 only if such delivery has been + accepted by contract. - d. Relevant information on multicast streams delivered to End Users - in AD-2 is assumed to be collected by available capabilities in - the application layer. The precise nature and formats of the - collected information will be determined by directives from the - source owner and the domain operators. + d. Relevant information on multicast streams delivered to End + Users in AD-2 is assumed to be collected by available + capabilities in the application layer. The precise nature and + formats of the collected information will be determined by + directives from the source owner and the domain operators. e. The interconnection of AD-1 and AD-2 should minimally follow guidelines for traffic filtering between autonomous systems - [BCP38]. Filtering guidelines specific to the multicast control- - plane and data-plane are described in section 6. - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 + [BCP38]. Filtering guidelines specific to the multicast + control-plane and data-plane are described in section 6. 3.2. Peering Point Enabled with GRE Tunnel The peering point is not native multicast enabled in this Use Case. There is a Generic Routing Encapsulation Tunnel provisioned over the peering point. In this case, the interconnection I1 between AD-1 and AD-2 in Figure 1 is multicast enabled via a Generic Routing Encapsulation Tunnel (GRE) [RFC2784] and encapsulating the multicast protocols across the interface. The routing configuration is basically unchanged: Instead of BGP (SAFI2) across the native IP multicast link between AD-1 and AD-2, BGP (SAFI2) is now run across the GRE tunnel. Advantages of this configuration: - o Highly efficient use of bandwidth in both domains although not as - efficient as the fully native multicast Use Case. + o Highly efficient use of bandwidth in both domains although not + as efficient as the fully native multicast Use Case. - o Fewer devices in the path traversed by the multicast stream when - compared to unicast transmissions. + o Fewer devices in the path traversed by the multicast stream + when compared to unicast transmissions. - o Ability to support only partial IP multicast deployments in AD-1 - and/or AD-2. + o Ability to support only partial IP multicast deployments in AD- + 1 and/or AD-2. o GRE is an existing technology and is relatively simple to implement. Disadvantages of this configuration: o Per Use Case 3.1, current router technology cannot count the number of end users or the number bytes transmitted. o GRE tunnel requires manual configuration. @@ -353,22 +340,20 @@ Architectural guidelines for this configuration include the following: Guidelines (a) through (d) are the same as those described in Use Case 3.1. Two additional guidelines are as follows: e. GRE tunnels are typically configured manually between peering points to support multicast delivery between domains. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - f. It is recommended that the GRE tunnel (tunnel server) configuration in the source network is such that it only advertises the routes to the application sources and not to the entire network. This practice will prevent unauthorized delivery of applications through the tunnel (e.g., if application - e.g., content - is not part of an agreed inter-domain partnership). 3.3. Peering Point Enabled with an AMT - Both Domains Multicast Enabled @@ -397,61 +382,57 @@ Figure 2 - AMT Interconnection between AD-1 and AD-2 Advantages of this configuration: o Highly efficient use of bandwidth in AD-1. o AMT is an existing technology and is relatively simple to implement. Attractive properties of AMT include the following: -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - o Dynamic interconnection between Gateway-Relay pair across the peering point. o Ability to serve clients and servers with differing policies. Disadvantages of this configuration: o Per Use Case 3.1 (AD-2 is native multicast), current router - technology cannot count the number of end users or the number of - bytes transmitted to all end users. + technology cannot count the number of end users or the number + of bytes transmitted to all end users. - o Additional devices (AMT Gateway and Relay pairs) may be introduced - into the path if these services are not incorporated in the - existing routing nodes. + o Additional devices (AMT Gateway and Relay pairs) may be + introduced into the path if these services are not incorporated + in the existing routing nodes. - o Currently undefined mechanisms for the AG to automatically select - the optimal AR. + o Currently undefined mechanisms for the AG to automatically + select the optimal AR. Architectural guidelines for this configuration are as follows: Guidelines (a) through (d) are the same as those described in Use Case 3.1. In addition, e. It is recommended that AMT Relay and Gateway pairs be configured at the peering points to support multicast delivery between domains. AMT tunnels will then configure dynamically across the peering points once the Gateway in AD-2 receives the (S, G) information from the EU. 3.4. Peering Point Enabled with an AMT - AD-2 Not Multicast Enabled In this AMT Use Case, the second administrative domain AD-2 is not multicast enabled. This implies that the interconnection between AD- 2 and the End User is also not multicast enabled as depicted in Figure 3. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - ------------------- ------------------- / AD-1 \ / AD-2 \ / (Multicast Enabled) \ / (Non-Multicast \ / \ / Enabled) \ | +----+ | | | | | | +------+ | | | +----+ | | AS |------>| AR |-|---------|-----------------------|-->|EU/G| | | | +------+ | | |I2 +----+ \ +----+ / \ / \ / \ / @@ -482,22 +463,20 @@ o Dynamic interconnection between Gateway-Relay pair across the peering point. o Ability to serve clients and servers with differing policies. o Each AMT tunnel serves as a count for each End User and is also able to track data usage (bytes) delivered to the EU. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - Disadvantages of this configuration: o Additional devices (AMT Gateway and Relay pairs) are introduced into the transport path. o Assuming multiple peering points between the domains, the EU Gateway needs to be able to find the "correct" AMT Relay in AD- 1. Architectural guidelines for this configuration are as follows: @@ -512,22 +491,20 @@ G) information to the Gateway for this purpose. e. The AMT tunnel capabilities are expected to be sufficient for the purpose of collecting relevant information on the multicast streams delivered to End Users in AD-2. 3.5. AD-2 Not Multicast Enabled - Multiple AMT Tunnels Through AD-2 This is a variation of Use Case 3.4 as follows: -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - ------------------- ------------------- / AD-1 \ / AD-2 \ / (Multicast Enabled) \ / (Non-Multicast \ / \ / Enabled) \ | +----+ | |+--+ +--+ | | | | +------+ | ||AG| |AG| | +----+ | | AS |------>| AR |-|-------->||AR|------------->|AR|-|-->|EU/G| | | | +------+ | I1 ||1 | I2 |2 | |I3 +----+ \ +----+ / \+--+ +--+ / \ / \ / @@ -546,34 +523,31 @@ Figure 4 - AMT Tunnel Connecting AD-1 AMT Relay and EU Gateway Use Case 3.4 results in several long AMT tunnels crossing the entire network of AD-2 linking the EU device and the AMT Relay in AD-1 through the peering point. Depending on the number of End Users, there is a likelihood of an unacceptably large number of AMT tunnels - and unicast streams - through the peering point. This situation can be alleviated as follows: o Provisioning of strategically located AMT nodes at the edges of - AD-2. An AMT node comprises co-location of an AMT Gateway and an - AMT Relay. One such node is at the AD-2 side of the peering point - (node AGAR1 in Figure 4). + AD-2. An AMT node comprises co-location of an AMT Gateway and + an AMT Relay. One such node is at the AD-2 side of the peering + point (node AGAR1 in Figure 4). o Single AMT tunnel established across peering point linking AMT Relay in AD-1 to the AMT Gateway in the AMT node AGAR1 in AD-2. o AMT tunnels linking AMT node AGAR1 at peering point in AD-2 to - other AMT nodes located at the edges of AD-2: e.g., AMT tunnel I2 - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - - linking AMT Relay in AGAR1 to AMT Gateway in AMT node AGAR2 in - Figure 4. + other AMT nodes located at the edges of AD-2: e.g., AMT tunnel + I2 linking AMT Relay in AGAR1 to AMT Gateway in AMT node AGAR2 + in Figure 4. o AMT tunnels linking EU device (via Gateway client embedded in device) and AMT Relay in appropriate AMT node at edge of AD-2: e.g., I3 linking EU Gateway in device to AMT Relay in AMT node AGAR2. The advantage for such a chained set of AMT tunnels is that the total number of unicast streams across AD-2 is significantly reduced thus freeing up bandwidth. Additionally, there will be a single unicast stream across the peering point instead of possibly, an @@ -602,69 +576,65 @@ 4. Supporting Functionality Supporting functions and related interfaces over the peering point that enable the multicast transport of the application are listed in this section. Critical information parameters that need to be exchanged in support of these functions are enumerated along with guidelines as appropriate. Specific interface functions for consideration are as follows. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - 4.1. Network Interconnection Transport and Security Guidelines The term "Network Interconnection Transport" refers to the interconnection points between the two Administrative Domains. The following is a representative set of attributes that will need to be agreed to between the two administrative domains to support multicast delivery. o Number of Peering Points. o Peering Point Addresses and Locations. - o Connection Type - Dedicated for Multicast delivery or shared with - other services. + o Connection Type - Dedicated for Multicast delivery or shared + with other services. - o Connection Mode - Direct connectivity between the two AD's or via - another ISP. + o Connection Mode - Direct connectivity between the two AD's or + via another ISP. - o Peering Point Protocol Support - Multicast protocols that will be - used for multicast delivery will need to be supported at these - points. Examples of protocols include eBGP [RFC4271] and MBGP - [RFC4271]. + o Peering Point Protocol Support - Multicast protocols that will + be used for multicast delivery will need to be supported at + these points. Examples of protocols include eBGP [RFC4271] and + MBGP [RFC4271]. - o Bandwidth Allocation - If shared with other services, then there - needs to be a determination of the share of bandwidth reserved - for multicast delivery. When determining the appropriate - bandwidth allocation, parties should consider that design of a - multicast protocol suitable for live video streaming which is - consistent with Congestion Control Principles [BCP41], especially - in the presence of potentially malicious receivers, is still an - open research problem. + o Bandwidth Allocation - If shared with other services, then + there needs to be a determination of the share of bandwidth + reserved for multicast delivery. When determining the + appropriate bandwidth allocation, parties should consider that + design of a multicast protocol suitable for live video + streaming which is consistent with Congestion Control + Principles [BCP41], especially in the presence of potentially + malicious receivers, is still an open research problem. o QoS Requirements - Delay/latency specifications that need to be specified in an SLA. o AD Roles and Responsibilities - the role played by each AD for - provisioning and maintaining the set of peering points to support - multicast delivery. + provisioning and maintaining the set of peering points to + support multicast delivery. 4.2. Routing Aspects and Related Guidelines The main objective for multicast delivery routing is to ensure that the End User receives the multicast stream from the "most optimal" source [INF_ATIS_10] which typically: -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - o Maximizes the multicast portion of the transport and minimizes any unicast portion of the delivery, and o Minimizes the overall combined network(s) route distance. This routing objective applies to both Native and AMT; the actual methodology of the solution will be different for each. Regardless, the routing solution is expected to be: o Scalable, @@ -697,26 +667,24 @@ data. The "S" portion provides the name or IP address of the source of the multicast stream. The metadata may also contain alternate delivery information such as specifying the unicast address of the stream. o The client uses the join message with S,G to join the multicast stream [RFC4604]. To facilitate this process, the two AD's need to do the following: -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - o Advertise the source id(s) over the Peering Points. - o Exchange relevant Peering Point information such as Capacity and - Utilization. + o Exchange relevant Peering Point information such as Capacity + and Utilization. o Implement compatible multicast protocols to ensure proper multicast delivery across the peering points. 4.2.2 GRE Tunnel over Interconnecting Peering Point If the interconnecting peering point is not multicast enabled and both ADs are multicast enabled, then a simple solution is to provision a GRE tunnel between the two ADs - see Use Case 3.2.2. The termination points of the tunnel will usually be a network @@ -744,23 +712,20 @@ o AMT Relays: These serve the purpose of tunneling UDP multicast traffic to the receivers (i.e., End Points). The AMT Relay will receive the traffic natively from the multicast media source and will replicate the stream on behalf of the downstream AMT Gateways, encapsulating the multicast packets into unicast packets and sending them over the tunnel toward the AMT Gateway. In addition, the AMT Relay may perform various usage and activity statistics collection. This results in moving the replication point closer to the end user, and cuts down on - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - traffic across the network. Thus, the linear costs of adding unicast subscribers can be avoided. However, unicast replication is still required for each requesting endpoint within the unicast-only network. o AMT Gateway (GW): The Gateway will reside on an on End-Point - this may be a Personal Computer (PC) or a Set Top Box (STB). The AMT Gateway receives join and leave requests from the Application via an Application Programming Interface (API). In this manner, the Gateway allows the endpoint to conduct itself @@ -794,23 +759,20 @@ for all AMT Gateways to find the "closest" AMT Relay - the nearest edge of the multicast topology of the source. Note that this is strictly illustrative; the choice of the method is up to the network operators. The basic process is as follows: o Appropriate metadata is obtained by the EU client application. The metadata contains instructions directing the EU client to an ordered list of particular destinations to seek the requested stream and, for multicast, specifies the source location and the group (or stream) ID in the form of the "S,G" data. The "S" - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - portion provides the URI (name or IP address) of the source of the multicast stream and the "G" identifies the particular stream originated by that source. The metadata may also contain alternate delivery information such as the address of the unicast form of the content to be used, for example, if the multicast stream becomes unavailable. o Using the information from the metadata, and possibly information provisioned directly in the EU client, a DNS query is initiated in order to connect the EU client/AMT Gateway to an AMT Relay. @@ -841,22 +803,20 @@ protocol messages). o AMT Relay receives the "S,G" information and uses the S,G to join the appropriate multicast stream, if it has not already subscribed to that stream. o AMT Relay encapsulates the multicast stream into the tunnel between the Relay and the Gateway, providing the requested content to the EU. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - 4.3. Back Office Functions - Provisioning and Logging Guidelines Back Office refers to the following: o Servers and Content Management systems that support the delivery of applications via multicast and interactions between ADs. o Functionality associated with logging, reporting, ordering, provisioning, maintenance, service assurance, settlement, etc. 4.3.1 Provisioning Guidelines @@ -886,23 +846,20 @@ Native multicast functionality is assumed to be available across many ISP backbones, peering and access networks. If however, native multicast is not an option (Use Cases 3.4 and 3.5), then: o EU must have multicast client to use AMT multicast obtained either from Application Source (per agreement with AD-1) or from AD-1 or AD-2 (if delegated by the Application Source). o If provided by AD-1/AD-2, then the EU could be redirected to a client download site (note: this could be an Application Source site). If provided by the Application Source, then this Source - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - would have to coordinate with AD-1 to ensure the proper client is provided (assuming multiple possible clients). o Where AMT Gateways support different application sets, all AD-2 AMT Relays need to be provisioned with all source & group addresses for streams it is allowed to join. o DNS across each AD must be provisioned to enable a client GW to locate the optimal AMT Relay (i.e. longest multicast path and shortest unicast tunnel) with connectivity to the content's multicast source. @@ -911,44 +868,42 @@ Each AD provider is assumed to provision operations and customer care access to their own systems. AD-1's operations and customer care functions must have visibility to what is happening in AD-2's network or to the service provided by AD-2, sufficient to verify their mutual goals and operations, e.g. to know how the EU's are being served. This can be done in two ways: o Automated interfaces are built between AD-1 and AD-2 such that - operations and customer care continue using their own systems. This - requires coordination between the two AD's with appropriate + operations and customer care continue using their own systems. + This requires coordination between the two AD's with appropriate provisioning of necessary resources. o AD-1's operations and customer care personnel are provided access - directly to AD-2's system. In this scenario, additional provisioning - in these systems will be needed to provide necessary access. - Additional provisioning must be agreed to by the two AD-2s to support - this option. + directly to AD-2's system. In this scenario, additional + provisioning in these systems will be needed to provide necessary + access. Additional provisioning must be agreed to by the two AD-2s + to support this option. 4.3.2 Application Accounting Guidelines All interactions between pairs of ADs can be discovered and/or be associated with the account(s) utilized for delivered applications. Supporting guidelines are as follows: o A unique identifier is recommended to designate each master account. o AD-2 is expected to set up "accounts" (logical facility generally protected by login/password/credentials) for use by AD-1. Multiple accounts and multiple types/partitions of accounts can apply, e.g. customer accounts, security accounts, etc. -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - 4.3.3 Log Management Guidelines Successful delivery of applications via multicast between pairs of interconnecting ADs requires that appropriate logs will be exchanged between them in support. Associated guidelines are as follows. AD-2 needs to supply logs to AD-1 per existing contract(s). Examples of log types include the following: o Usage information logs at aggregate level. @@ -979,88 +934,84 @@ agreement). 4.4. Operations - Service Performance and Monitoring Guidelines Service Performance refers to monitoring metrics related to multicast delivery via probes. The focus is on the service provided by AD-2 to AD-1 on behalf of all multicast application sources (metrics may be specified for SLA use or otherwise). Associated guidelines are as follows: -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - o Both AD's are expected to monitor, collect, and analyze service performance metrics for multicast applications. AD-2 provides relevant performance information to AD-1; this enables AD-1 to - create an end-to-end performance view on behalf of the multicast - application source. + create an end-to-end performance view on behalf of the + multicast application source. - o Both AD's are expected to agree on the type of probes to be used - to monitor multicast delivery performance. For example, AD-2 may - permit AD-1's probes to be utilized in the AD-2 multicast service - footprint. Alternately, AD-2 may deploy its own probes and relay - performance information back to AD-1. + o Both AD's are expected to agree on the type of probes to be + used to monitor multicast delivery performance. For example, + AD-2 may permit AD-1's probes to be utilized in the AD-2 + multicast service footprint. Alternately, AD-2 may deploy its + own probes and relay performance information back to AD-1. - o In the event of performance degradation (SLA violation), AD-1 may - have to compensate the multicast application source per SLA + o In the event of performance degradation (SLA violation), AD-1 + may have to compensate the multicast application source per SLA agreement. As appropriate, AD-1 may seek compensation from AD-2 if the cause of the degradation is in AD-2's network. Service Monitoring generally refers to a service (as a whole) provided on behalf of a particular multicast application source provider. It thus involves complaints from End Users when service problems occur. EU's direct their complaints to the source provider; in turn the source provider submits these complaints to AD-1. The responsibility for service delivery lies with AD-1; as such AD-1 will need to determine where the service problem is occurring - its own network or in AD-2. It is expected that each AD will have tools to monitor multicast service status in its own network. o Both AD's will determine how best to deploy multicast service monitoring tools. Typically, each AD will deploy its own set of - monitoring tools; in which case, both AD's are expected to inform - each other when multicast delivery problems are detected. + monitoring tools; in which case, both AD's are expected to + inform each other when multicast delivery problems are + detected. o AD-2 may experience some problems in its network. For example, - for the AMT Use Cases, one or more AMT Relays may be experiencing - difficulties. AD-2 may be able to fix the problem by rerouting - the multicast streams via alternate AMT Relays. If the fix is not - successful and multicast service delivery degrades, then AD-2 - needs to report the issue to AD-1. + for the AMT Use Cases, one or more AMT Relays may be + experiencing difficulties. AD-2 may be able to fix the problem + by rerouting the multicast streams via alternate AMT Relays. If + the fix is not successful and multicast service delivery + degrades, then AD-2 needs to report the issue to AD-1. o When problem notification is received from a multicast application source, AD-1 determines whether the cause of the problem is within its own network or within the AD-2 domain. If the cause is within the AD-2 domain, then AD-1 supplies all - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - - necessary information to AD-2. Examples of supporting information - include the following: + necessary information to AD-2. Examples of supporting + information include the following: o Kind of problem(s). o Starting point & duration of problem(s). o Conditions in which problem(s) occur. o IP address blocks of affected users. o ISPs of affected users. o Type of access e.g., mobile versus desktop. o Locations of affected EUs. - o Both AD's conduct some form of root cause analysis for multicast - service delivery problems. Examples of various factors for - consideration include: + o Both AD's conduct some form of root cause analysis for + multicast service delivery problems. Examples of various + factors for consideration include: o Verification that the service configuration matches the product features. o Correlation and consolidation of the various customer problems and resource troubles into a single root service problem. o Prioritization of currently open service problems, giving consideration to problem impact, service level agreement, @@ -1069,30 +1020,28 @@ o Conduction of service tests, including one time tests or a series of tests over a period of time. o Analysis of test results. o Analysis of relevant network fault or performance data. o Analysis of the problem information provided by the customer (CP). - o Once the cause of the problem has been determined and the problem - has been fixed, both AD's need to work jointly to verify and - validate the success of the fix. - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 + o Once the cause of the problem has been determined and the + problem has been fixed, both AD's need to work jointly to + verify and validate the success of the fix. o Faults in service could lead to SLA violation for which the - multicast application source provider may have to be compensated - by AD-1. Subsequently, AD-1 may have to be compensated by AD-2 - based on the contract. + multicast application source provider may have to be + compensated by AD-1. Subsequently, AD-1 may have to be + compensated by AD-2 based on the contract. 4.5. Client Reliability Models/Service Assurance Guidelines There are multiple options for instituting reliability architectures, most are at the application level. Both AD's should work those out with their contract/agreement and with the multicast application source providers. Network reliability can also be enhanced by the two AD's by provisioning alternate delivery mechanisms via unicast means. @@ -1121,23 +1070,20 @@ easily extended to provide access to commonly-used multicast troubleshooting commands in a secure manner. The specifics of the notification and alerts are beyond the scope of this document, but general guidelines are similar to those described in section 4.4 (Service Performance and Monitoring). Some general communications issues are stated as follows. o Appropriate communications channels will be established between the customer service and operations groups from both AD's to - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - facilitate information sharing related to diagnostic troubleshooting. o A default resolution period may be considered to resolve open issues. Alternately, mutually acceptable resolution periods could be established depending on the severity of the identified trouble. 6. Security Considerations @@ -1145,22 +1091,22 @@ to be followed by each AD to facilitate multicast delivery to registered and authenticated end users. Additionally: o Encryption - Peering point links may be encrypted per agreement if dedicated for multicast delivery. o Security Breach Mitigation Plan - In the event of a security breach, the two AD's are expected to have a mitigation plan for shutting down the peering point and directing multicast traffic over alternated peering points. It is also expected that - appropriate information will be shared for the purpose of securing - the identified breach. + appropriate information will be shared for the purpose of + securing the identified breach. DRM and Application Accounting, Authorization and Authentication should be the responsibility of the multicast application source provider and/or AD-1. AD-1 needs to work out the appropriate agreements with the source provider. Network has no DRM responsibilities, but might have authentication and authorization obligations. These though are consistent with normal operations of a CDN to insure end user reliability, security and network security. @@ -1170,23 +1116,20 @@ point and separately the number of bytes delivered to EUs. For example, [BCP38] style filtering could be deployed by both AD's to ensure that only legitimately sourced multicast content is exchanged between them. Authentication and authorization of EU to receive multicast content is done at the application layer between the client application and the source. This may involve some kind of token authentication and is done at the application layer independently of the two AD's. If there are problems related to failure of token authentication when - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - end-users are supported by AD-2, then some means of validating proper working of the token authentication process (e.g., back-end servers querying the multicast application source provider's token authentication server are communicating properly) should be considered. Implementation details are beyond the scope of this document. 7. IANA Considerations No considerations identified in this document @@ -1209,31 +1152,26 @@ 9. References 9.1. Normative References [RFC2784] D. Farinacci, T. Li, S. Hanks, D. Meyer, P. Traina, "Generic Routing Encapsulation (GRE)", RFC 2784, March 2000 [RFC3376] B. Cain, et al, "Internet Group Management Protocol, Version 3", RFC 3376, October 2002 - [RFC3618] B. Fenner, et al, "Multicast Source Discovery Protocol", - RFC 3618, October 2003 - [RFC3810] R. Vida and L. Costa, "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, June 2004 [RFC4271] Y. Rekhter, et al, "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006 -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - [RFC4604] H. Holbrook, et al, "Using Internet Group Management Protocol Version 3 (IGMPv3) and Multicast Listener Discovery Protocol Version 2 (MLDv2) for Source Specific Multicast", RFC 4604, August 2006 [RFC4609] P. Savola, et al, "Protocol Independent Multicast - Sparse Mode (PIM-SM) Multicast Routing Security Issues and Enhancements", RFC 4609, August 2006 [RFC7450] G. Bumgardner, "Automatic Multicast Tunneling", RFC 7450, @@ -1258,29 +1196,26 @@ [MDH-04] D. Thaler, et al, "Multicast Debugging Handbook", IETF I-D draft-ietf-mboned-mdh-04.txt, May 2000 [Traceroute] http://traceroute.org/#source%20code [draft-MTraceroute] H. Asaeda, K, Meyer, and W. Lee, "Mtrace Version 2: Traceroute Facility for IP Multicast", draft-ietf-mboned-mtrace- v2-16, October 2016, work in progress -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - 10. Acknowledgments The authors would like to thank the following individuals for their suggestions, comments, and corrections: Mikael Abrahamsson - Hitoshi Asaeda Dale Carder Tim Chown Leonard Giuliano Jake Holland @@ -1282,39 +1217,36 @@ Leonard Giuliano Jake Holland Joel Jaeggli Albert Manfredi Stig Venaas - -IETF I-D Multicast Across Inter-Domain Peering Points February 2017 - Authors' Addresses Percy S. Tarapore AT&T Phone: 1-732-420-4172 Email: tarapore@att.com Robert Sayko AT&T Phone: 1-732-420-3292 Email: rs1983@att.com Greg Shepherd Cisco Phone: Email: shep@cisco.com Toerless Eckert - Cisco + Futurewei Technologies Inc. Phone: Email: tte@cs.fau.de Ram Krishnan SupportVectors Phone: Email: ramkri123@gmail.com