Internet Draft A.Uzelac, Ed. SPEERMINT Global Crossing Intended status: Informational Y.Lee, Ed. Expires: Aug 2008 Comcast February 4, 2008 VoIP SIP Peering Use Cases draft-ietf-speermint-voip-consolidated-usecases-05.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on Aug 4, 2008. Abstract This document will capture VoIP use case for SIP Peering. This document depicts many common VoIP peering use cases. These use cases are categorized into two types: static and on-demand, and then further subcategorized into direct and indirect. These use cases are not an exhaustive set, but rather the most common use cases deployed today. This document captures them to provide a reference. Uzelac, Lee (et al) Expires Aug 4, 2008 [Page 1] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 Table of Contents 1. Introduction...................................................2 2. Terminology....................................................3 3. Reference Architecture.........................................3 4. Contexts of Use Cases..........................................4 5. Use Cases......................................................5 5.1. Static Peering Use Cases..................................5 5.1.1. Static Direct Peering Use Case..........................6 5.1.1.1. Administrative characteristics........................7 5.1.1.2. Options and Nuances...................................7 5.1.2. Static Direct via Assisting Entity (Hub/Spoke)..........7 5.1.2.1. Administrative Characteristics........................8 5.1.2.2. Options and Nuances...................................8 5.1.3. Static Indirect Use Cases...............................9 5.1.4. Static Indirect Peering ? SIP and Media via I-SSP.......9 5.1.4.1. Administrative characteristics.......................10 5.1.4.2. Options and Nuances..................................10 5.1.5. Static Indirect ? Signaling via I-SSP..................11 5.2. On-demand Peering Use Cases..............................12 5.2.1. On-demand Direct Peering Use Case......................12 5.2.1.1. Administrative characteristics.......................12 5.2.1.2. Options and Nuances..................................12 5.3. Federations..............................................13 5.3.1. Federation Considerations..............................13 5.3.2. Federation Examples....................................13 5.3.2.1. Trivial Federations..................................13 5.3.2.2. Access List based....................................14 5.3.2.3. TLS based Federations................................14 5.3.2.4. Central SIP Proxy....................................14 6. Architecture, scalability and business scalability............15 7. Security Considerations.......................................15 8. IANA Considerations...........................................15 References.......................................................16 Normative References..........................................16 Informative References........................................17 Author's Addresses............................................17 Full Copyright Statement......................................18 Intellectual Property.........................................18 Acknowledgment................................................18 1. Introduction This document attempts to capture VoIP use cases for Session Initiation Protocol (SIP)[1] based peering. These use cases will Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 2] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 assist in identifying requirements and future works for VoIP Peering using SIP. Only use cases related to VoIP are considered in this document. Other real-time SIP communications use cases, like Instant Messaging (IM) and presence are out of scope for this document. In describing use cases, the intent is descriptive, not prescriptive. There are existing documents [2][3][4][5][6] that have captured use case scenarios. This draft draws from those documents. The document categories use cases into the following groupings; static or on- demand, then they are further subdivided into direct and indirect. Using this categorization, the use cases contained in this document attempts to be as comprehensive as possible, but should not be considered the exclusive set of use cases. 2. Terminology In this document, we use ?O? to indicate ?Originating?, ?T? to indicate ?Terminating?, and ?I? to indicate ?Indirect?. For example, O-SSP is the acronym of Originating SIP Service Provider. 3. Reference Architecture The diagram below provides the reader with a context for the VoIP use cases in this draft. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 3] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 +-------------------+-------------------------+-------------------+ | | Indirect SSP Domain | | | | | | | | +------+ +------+ | | | | +I-LUF + + I-LRF| | | | | +------+ +------+ | | | | | | | | +-------+ | | | | |I-Proxy| | | | | +-------+ | | | | | | | | +------+ +------+ | | | | | I-SBE| | I-DBE| | | | \ +------+ +------+ / | | +------+ \ / +------+ | | +-----+O-LUF + \ / +T-LUF +-----+ | | | +O-LRF + \ / +T-LRF + | | | | +------+ \ / +------+ | | | | \ / | | | | +------+ \ / +------+ | | | | | O-SBE+ \ / + T-SBE| | | | | +---+--+ \ / +---+--+ | | | | | \ / | | | | | | \ / | | | | | +---+---+ \ / +---+---+ | | | +-----+O-Proxy| \ / |T-Proxy+--- + | | +-----+-+ + ++------+ | | +----+ | | | +----+ | | |UAC +---------+ | +---------+ UAS| | | +----+ +------+ | +------+ +----+ | | | O-DBE| | | T-DBE| | | +------+ | +------+ | | | | | Originating SSP Domain | Terminating SSP Domain | +-----------------------------------------------------------------+ Figure 1 Generalized Overview PLEASE NOTE: In figure one ? the elements defined are optional in many use cases. 4. Contexts of Use Cases Use cases are sorted into two general groupings: Static and On-demand Peering [15]. Each grouping can further sub-divided to Direct Peering and Indirect Peering [15]. Though there may be some overlap among the use cases in these categories, there are different requirements between the scenarios. Each use-case has to specify how a few core operations which are to be performed by its members. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 4] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 These can include: 1) Peer Discovery via a Look-up function to determine the administrative domain to direct the call to. 2) A location determination process that serves to create the Session Establishment Data (SED). Examples: Public User-ENUM, public Infrastructure ENUM, private ENUM tree, SIP Redirect, DUNDi. 3) Next Hop determination based on the SED. If a location function query did not return an URI of the form sip:user@IP-address, then the originating SSP has to translate the domain part of the URI to an IP- address (plus perhaps fall-backs) in order to contact the next hop. Examples: RFC3263 in the public DNS. RFC3263 in a federation private DNS. RFC3263 in the public DNS with split-DNS, P2P SIP, modified RFC3263 in the public DNS (e.g. a federation-specific prefix to the domain name). 4) Call setup ? SSPs that are interconnecting to one another may also define specifics on what SIP features need to be used when contacting the next hop in order to a) reach the next hop at all and b) to prove that the sender is a legitimate peering partner. Examples: hard-code transport (TCP/UDP/TLS), non-standard port number, specific source IP address (e.g. in a private L3 network), which TLS client certificate to use, other authentication scheme. 5) Call reception ? This step serves to ensure that the type of relationship (static or on-demand, indirect or direct) is understood. For instance, the receiving side border elements need to determine whether the INVITE it just received really came from a member of the federation. This is the flip side of step four. Example: verify TLS cert, check incoming interface/VLAN,check source IP address against a configured list of valid ones. 5. Use Cases Please note there are intra-domain message flows within the use cases to serve as supporting background information. Only inter-domain communications are germane to Speermint. 5.1. Static Peering Use Cases Static Peering [15] describes two SSP form the peering relationship with pre-association. Pre-association is a prerequisite to static peering. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 5] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 5.1.1. Static Direct Peering Use Case This is the simplest form of a peering use case. Two SSP negotiate and agree to establish a SIP peering relation. The peer connection is statically configured and directly connected two SSP. The peers may exchange peer information such as DSCP policies, subscriber SIP-URI and proxy location prior to establishing the connection. They only accept traffic originating directly from the trusted peer. +------------------+-------------------+ | Orig SSP | Term SSP | | +--------+ | +--------+ | | | O-LUF | | | T-LUF | | | | O-LRF | | | T-LRF | | | +--------+ | +--------+ | | (2) / | | | /(3) | | | +-------+ | +-------+ | | |O-Proxy|------(4)------|T-Proxy| | | +-------+ | +-------+ | | | | | | | (1) | (5) | | | | | | | +----+ | +----+ | | | UAC+===(6)=(RTP)=======+ UAS+ | | +----+ | +----+ | +------------------+-------------------+ Figure 2 Direct Peering The following is a high-level depiction of the use case. 1. UAC initiates a call via SIP INVITE 2. O-Proxy queries for SED information from a routing database. 3. Routing database entity replies with SED to called party 4. Call sent to terminating domain proxy. 5. T-Proxy determines called party status and directs call to called party. 6. RTP is established between UAC and UAS. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 6] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 5.1.1.1. Administrative characteristics The static direct peering use case is typically implemented in a scenario where exists a strong degree of trust between the two administrative domains. Both administrative domains normally sign a peer agreement which state clearly the peering policies and terms. 5.1.1.2. Options and Nuances In Figure 2, O-Proxy and T-Proxy connect directly. An operator may decide to deploy a SBE between its proxy and the peer network. Normally, the operator will deploy the SBE in the edge of its administrative domain. The signaling traffic will pass between two networks through the SBE. The operator has many reasons to deploy a SBE. For example, the proxy may use RFC1918 addresses that are not routable in the peer operator network. The SBE can perform a NAT function. Also, the SBE eases the operation cost for deploying or removing L5 network elements. Consider the deployment architecture where multiple proxies connect to a single SBE. An operator can add or remove a proxy without coordinating with the peer operator. The peer operator ?sees? only the SBE. As long as the SBE maintain intact, the peer operator does not need to be notified. When an operator deploys a SBE, the operator is required to advertise the SBE to the peer LRF so that the peer operator can locate the SBE and route the traffic to the SBE accordingly. SBE deployment is a decision within an administrative domain. Either administrative domain or both administrative domains can decide to deploy SBE. To the peer network, most important is to identify the next-hop address. Whether next-hop is a proxy or SBE, the peer network will not see any difference. 5.1.2. Static Direct via Assisting Entity (Hub/Spoke) The difference between Direct and Indirect Use Cases is the O-SSP invokes an I-SSP to forward requests to T-SSP blindly, regardless of LUF or LRF. This use case is also referring to a ?transit? model of SIP peering. Similar to the On-demand Direct Use Case model, the I- SSP must publicly announce that it accepts request and is capable to route the request to the T-SSP. Another On-demand Indirect Use Case is the Hub-and-Spoke use case. An Assisting entity where only the LRF resides, serves as the hub for multiple SSPs. Each SSP is the spoke to the Assisting Entity which does not need to have direct L5 connections among other SSPs. To originate a call to a T-SSP, the O-SSP will query the Assisting Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 7] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 Entity?s LRF. The response will facilitate indirect or direct communications to the O-SSP. The Assisting entity can route the Session to one of its served SSP. The routing logic in the Assisted Entity is hidden to the SSP. Figure 4 shows the high-level network setup. +---------+ |Assisting| | Entity | | (LRF) | +--+-+-+--+ | | | | | | | | | +----------------+ | +------------------+ | | | | | | | | | +---+----+ +---+----+ +---+----+ | | | | | | | SSP1 | | SSP2 | ....... | SSPx | | | | | | | +--------+ +--------+ +--------+ Figure 3 Hub and spoke 5.1.2.1. Administrative Characteristics The Hub-and-Spoke Use Case is commonly used in a Registry or Directory call model, where both O-SSP and T-SSP do not have direct Layer-5 connectivity. O-SSP and T-SSP choose an I-SSP and forms a trusted relationship to I-SSP. As such, the I-SSP is the hub served multiple spoke SSPs. Spoke SSP only have trusted relationship with I- SSP. Spoke SSPs do not have trusted relationship among themselves. They use I-SSP to assist them to route the signaling traffic. That said, if Spoke SSPs have direct Layer-3 connectivity, Spoke SSP can choose not to use I-SSP assistance for media traffic. 5.1.2.2. Options and Nuances T-SSP shares the same problems of which On-demand Indirect Use Case suffers. T-SSP should apply filter rules for VoIP spam. O-SSP, T-SSP and I-SSP can deploy SBE and DBE for NAT traversal, admission control and codec Transcoding. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 8] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 5.1.3. Static Indirect Use Cases Similar to the Static Direct Peering Use Case, O-SSP and T-SSP has pre-arranged assignment for the peer relationship. The difference between Static Direct Use Case and Static Indirect Use Case lies with the Layer-5 relationship O-SSP and T-SSP maintain. In the Indirect use case, the O-SSP and T-SSP do not have direct Layer-5 connectivity. They require one or multiple Indirect Domains to assist routing the SIP messages and possibly the associated media. 5.1.4. Static Indirect Peering ? SIP and Media via I-SSP In the following use case, all signaling and media between the O-SSP and T-SSP flows through another SSP (Indirect SSP). +--------------------+ | Indirect SSP | | | | +-------+ | | +--+I-Proxy| | | / +-+ I-LUF | | | / / + I-LRF | | +--------------------+ / / +-------+ +---------------------+ | Orig SSP |/ / | Term SSP | | +-------------/ / | | | / |/ | | | / +----(3)-----+ | | | (2) / | | | | / / | | | |+-------+ +-----+ +-----+ +-----+ +-------+ | ||O-Proxy|-(4)-|O-SBE|------+I-SBE+--(5)--+T-SBE+-(6)-|T-Proxy| | |+-------+ +-----+ +-----+ +-----+ +-------+ | | | | | | | | (1) | | (7) | | | | | | | | +-----+ +-----+ +-----+ +-----+ +-----+ | | | UAC +======|0-DBE|=(8)==+I-DBE+=======+T-DBE+======+ UAS | | | +-----+ +-----+ +-----+ +-----+ +-----+ | +---------------------------------------------------------------+ Figure 4 Indirect Peering via Indirect Domain (SIP and media) 1. UAC initiates a call. 2. The O-Proxy queries SED for the called party. O-SSP can query its own LUF and LF for the SED if the information is available within its domain. Alternatively, the I-SSP may provide the LUF Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 9] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 and LF for the O-SSP. In this setup, the query traverses the administrative boundary between the originating and the Indirect domains (as illustrated in Fig. 3). 3. The result of the query will be the I-SSP?s SBE (I-SBE) that is interconnected to the T-SSP and the O-SBE. 4. O-Proxy signals the I-SBE via the O-SBE. 5. I-SBE routes call to T-SBE within T-SSP. 6. T-SBE signals T-Proxy. 7. T-Proxy signals the called party. (UAS) 8. RTP may be established between UAC and UAS via DBE path typically coordinated by the I-SSP. 5.1.4.1. Administrative characteristics The Static Indirect Use Case is normally implemented in cases where no direct interconnection exists between originating and terminating domains due to either business or physical constraints. O-SSP .--. I-SSP = Relationship O-I In the O-I relationship, typical policies, features or functions that deem this relationship necessary are NP, Ubiquity of termination options, and masquerading of originating VoIP network gear. T-SSP .--. I-SSP = Relationship T-I In the T-I relationship, typical policies, features or functions observed consist of codec ?scrubbing?, anonimizing, and transcoding. I-SSP must record-route and stay in the signalling path. T-SSP will not accept message directly sent from O-SSP. 5.1.4.2. Options and Nuances Similar to the Static Direct Peering Use Case, O-SSP and T-SSP may deploy SBE and DBE for NAT traverse, security Transcoding, etc. I-SSP can also deploy SBE and DBE for similar reasons. (as depicted in Fig. 3) Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 10] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 5.1.5. Static Indirect ? Signaling via I-SSP The static indirect use case with signaling only shares many properties with the static indirect use case for signaling and media. There must exist a pre-associate between the O-SSP and T-SSP, but the situation only pertains to administrative relations. The O and T SSPs do not have direct Layer-5 connectivity; therefore require one or multiple Indirect Domains to assist routing the SIP messages. +--------------------+ | Indirect SSP | | | | +-------+ | | +--+I-Proxy| | | / +-+ I-LUF | | | / / + I-LRF | | +--------------------+ / / +-------+ +---------------------+ | Orig SSP |/ / | Term SSP | | +-------------/ / | | | / |/ | | | / +----(3)-----+ | | | (2) / +--------------------+ | | / / | | | |+-------+ +-----+ +-----+ +-------+ | ||O-Proxy|-----|O-SBE+--------(4)---------+T-SBE+-(5)-|T-Proxy| | |+-------+ +-----+ +-----+ +-------+ | | | | | | | | (1) | | (6) | | | | | | | | +-----+ +-----+ +-----+ +-----+ | | | UAC +======|0-DBE|========(7)=========+T-DBE+======+ UAS | | | +-----+ +-----+ +-----+ +-----+ | +--------------------+ +---------------------+ Figure 5 Indirect via I-SSP (SIP only) 1. UAC initiates a call. 2. The O-Proxy queries SED for the called party. O-SSP can query its own LUF and LF for the SED if the information is available within its domain. Alternatively, the I-SSP may provide the LUF and LF for the O-SSP. In this setup, the query traverses the administrative boundary between the originating and the Indirect domains (as illustrated in Fig. 4). 3. The result of the query will be the T-SSP?s SBE (T-SBE) that is interconnected to the O-SSP via the O-SBE. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 11] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 4. O-SBE signals the T-SBE. 5. T-SBE signals T-Proxy. 6. T-Proxy signals the called party, UAS. 7. RTP may be established between UAC and UAS via DBE path typically coordinated by the I-SSP. 5.2. On-demand Peering Use Cases On-demand Peering [15] describes two SSPs form the peering relationship without a pre-arranged agreement. 5.2.1. On-demand Direct Peering Use Case The basis of this use case is built on the fact that there is NOT a pre-established relationship between the O-SSP and the T-SSP. The O- SSP and T-SSP did not share any information prior to the dialog initiation request. When the O-Proxy invokes the LUF and LRF on the R-URI, the terminating user information must be publicly available. Besides, when the O-Proxy routes the request to the T-Proxy, the T- Proxy must accept the request without any pre-association with O-SSP. The call flow is identical to the Static Direct Peering Use Case shown in Fig 2. 5.2.1.1. Administrative characteristics The On-demand Direct Peering Use Case is typically implemented in a scenario where the T-SSP allows any O-SSP to reach its serving subscribers. T-SSP administrative domain does not require any pre- arranged agreement to accept the call. T-SSP makes its subscribers information available in public. This model mimics the Internet email model. Sender does not need an pre-arranged agreement to send email to the receiver. 5.2.1.2. Options and Nuances Similar to Static Direct Peering Use Case, O-SSP and T-SSP can decide to deploy SBE. T-SSP is open to the public, T-SSP should prepare to suffer from the spam problem existing in email system. VoIP spamming is considered more annoying than email spamming to the subscribers. T-SSP should apply rules to filter spammed calls. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 12] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 5.3. Federations This section discusses the federation concept, explains which technical parameters make up the foundation of a federation and provides examples. The concrete implementation details (e.g. "direct with one SBE" versus "direct with two SBEs") can involve all the use cases thus far described in the document. 5.3.1. Federation Considerations 5.3.2. Federation Examples This section lists some examples of how federations can operate. 5.3.2.1. Trivial Federations A private peering arrangement between two SSPs is a special case of a federation. These two SSP have agreed to exchange calls amongst themselves and they have set up whatever LUF/LS/SBE plus Layer 3 infrastructure they need to route and complete the calls. This can be in a direct or indirect manner, but usually follows the direct call model. It is thus not needed to treat bi-lateral peerings as conceptually different to federation-based peering. On the other extreme, the set of all SSPs implementing an open SIP service according to RFCs 3261/3263/3761 also fulfills the definition of a federation. In that case, the technical rules are contained in these three RFCs, the LS is the public DNS. Whether some of these SSPs use SBCs as border elements is not relevant. The administrative model of this federation is the "email model": There is no "member list", any SIP server operating on the Internet which implements call routing according to these RFCs is implicitly a member of that federation. No business relationship is needed between "members", thus no money is likely to change hands for terminating calls. There is no contractual protection against nuisance calls, SPIT, or denial of service attacks. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 13] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 5.3.2.2. Access List based If running an open SIP proxy is not desired, then a group of SSPs which want to allow calls from each other can collect the list of IP addresses of all their border elements. This list is redistributed to all members which use it to configure firewalls in front of their ingress elements. Thus calls from other members of this federation are accepted while calls from other hosts on the Internet are blocked. Whether SSPs deploy SBEs as border elements is not relevant. Call routing can still be done via standard RFC rules. Whenever a new member joins this club every other SSP needs to adapt its filter rules. 5.3.2.3. TLS based Federations Another option to restrict incoming calls to federation members is to use Transport Layer Security (TLS) certificates as access control. This works best if the federation runs a certificate authority (CA) which signs the TLS keys of each member SSP. Thus the ingress element of a SSP needs to check only whether the client certificate presented by the calling SIP proxy contains a proper signature from that CA. Adding support for Certificate Revocation Lists solves the issue of blocking calls from former members of that federation. The main benefit of this model is that no changes need to be made at the ingress element of all old members whenever a SSP joins that federation. 5.3.2.4. Central SIP Proxy One way to simplify the management of these firewall rules is to route all SIP messages via a central proxy. In that case, all federation members just need to open up their ingress elements to requests from that central server. A new SSP just triggers a change in the configuration of this box and not at all other SSPs. While centralized solutions may entail typical hub-and-spoke architecture considerations, the added overall federation scalability with respect to the number of interconnects required, Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 14] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 their associated policies and management make this approach quite popular today. This is an example of Indirect Peering. 6. Architecture, scalability and business scalability The network architecture which in the case centralized model would reflect a hub and spoke model - should be weighed against a distributed model. While such a centralized model presents well- known network and server scalability challenges, a distributed model requires higher interconnection complexity, reflected in provisioning and the need for the maintenance of such relationships. 7. Security Considerations This document introduces no new security considerations. However, it is important to note that session interconnect, as described in this document, has a wide variety of security issues that should be considered in documents addressing both protocol and use case analyzes. 8. IANA Considerations This document creates no new requirements on IANA namespaces [RFC2434]. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 15] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 References Normative References [1] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, June 2002. [2] Schwartz, David, draft-schwartz-speermint-use-cases-federations [3] Mahy, Rohan, draft-mahy-speermint-direct-peering [4] Lendl, Otmar, draft-lendl-speermint-federations [5] Lee, Yiu, draft-lee-speermint-use-case-cable [6] Uzelac, Adam, draft-uzelac-speermint-use-cases [7] Rosenberg, J. and H. Schulzrinne, "Session Initiation Protocol (SIP): Locating SIP Servers", RFC 3263, June 2002. [8] Blake-Wilson, S., Nystrom, M., Hopwood, D., Mikkelsen, J., and T. Wright, "Transport Layer Security (TLS) Extensions", RFC 3546, June 2003. [9] Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications", STD 64, RFC 3550, July 2003. [10] Peterson, J., Liu, H., Yu, J., and B. Campbell, "Using E.164 numbers with the Session Initiation Protocol (SIP)", RFC 3824, June 2004. [11] Peterson, J., ?Address Resolution for Instant Messaging and Presence?,RFC 3861, August 2004. [12] Peterson, J., "Telephone Number Mapping (ENUM) Service Registration for Presence Services", RFC 3953, January 2005. [13] ETSI TS 102 333: " Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Gate control protocol". [14] Peterson, J., "enumservice registration for Session Initiation Protocol (SIP) Addresses-of-Record", RFC 3764, April 2004. Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 16] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 Informative References [15] Meyer, D., "SPEERMINT Terminology", draft-ietf-speermint- terminology-06 (work in progress), 2006. [16] Mule, J-F., ?SPEERMINT Requirements for SIP-based VoIP Interconnection?, draft-ietf-speermint-requirements-00.txt, June 2006. [17] Camarillo, G. ?Requirements from SIP (Session Initiation Protocol) Session Border Control Deployments?, draft-camarillo- sipping-sbc-funcs-04.txt, June, 2006. [18] Habler, M., et al., ?A Federation based VOIP Peering Architecture?, draft-lendl-speermint-federations-03.txt, September 2006. Author's Addresses Adam Uzelac Global Crossing Email: adam.uzelac@globalcrossing.com Rohan Mahy Plantronics Email: rohan@ekabal.com Yiu L. Lee Comcast Cable Communications Email: yiu_lee@cable.comcast.com David Schwartz Xconnect Global Networks Email: dschwartz@xconnect.net Eli Katz Xconnect Global Networks Email: ekatz@xconnect.net Otmar Lendl enum.at GmbH Email: otmar.lendl@enum.at Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 17] Internet-Draft draft-ietf-speermint-voip-consolidated-usecases Aug 2008 Full Copyright Statement Copyright (C) The IETF Trust (2008). 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The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf- ipr@ietf.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Uzelac, Lee (et al.) Expires Aug 4, 2008 [Page 18]