Internet Engineering Task Force Gorry Fairhurst Internet Draft University of Aberdeen, U.K. Document: draft-fair-ipdvb-ar-01.txt Marie-Jose Montpetit July 2004 MJMontpetit.com Category: Informational Expires November 2004 Address Resolution for IP datagrams over MPEG-2 networks Status of this Memo By submitting this Internet-Draft, we certify that any applicable patent or other IPR claims of which we am aware have been disclosed, or will be disclosed, and any of which we become aware will be disclosed, in accordance with RFC 3668. By submitting this Internet-Draft, we accept the provisions of Section 3 of RFC 3667 (BCP 78). 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/ietf/1id-abstracts.txt. The list of Internet- Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Copyright (C) The Internet Society (2004), All Rights Reserved Expires November 2004 [page 1] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 Abstract This document describes mechanisms to bind IPv4/IPv6 addresses and flows to MPEG-2 Transport Streams (TS). While methods currently exist to perform these bindings, for MPEG-2 systems to become true subnetworks of the general Internet, protocols are required to signal IPv4/v6 addresses to the link receivers and transmitters. This is known as Address Resolution (AR), or Neighbour Discovery (ND). Although AR is often associated with Ethernet [RFC803], it is essential to the operation of any L2 network. MPEG-2 transmission networks often utilize broadcast media (e.g. satellite or cable) where the mapping may take into account issues related to network operations and traffic engineering. In MPEG-2 networks, an IP address must be associated with a Packet ID (PID) and specific transmission multiplex. Address resolution complements the higher layer resource discovery tools that are used to advertise IP sessions. In this document the different mechanisms used for address resolution for MPEG-2 are reviewed and guidelines for future developments of efficient schemes are given. Table of Contents Document History 1. Introduction 2. Convention used in the document 3. Address Resolution Requirement 4. MPEG-2 Address Resolution Operation 5. Conclusions and Recommendations 6. Security Considerations 7. Acknowledgements 8. References 9. Author's Addresses 10. IPR Notices 11. Copyright Statements 12. IANA Considerations Document History -00 This draft is intended as a study item for proposed future work by the IETF in this area. -01 Review of initial content, major edit and refinement of concepts Expires November 2004 [page 2] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 1. Introduction The MPEG-2 stream is defined in the specification ISO/IEC 138181. It provides a time-division multiplexed (TDM) stream that may contain audio, video and other information. Each frame, known as an MPEG-2 TS Packet, contains 4 bytes of header and 188 bytes of data. The standard also defines the PES packet (Packetized Elementary Stream) and the Section or Transport Stream (TS) packet. The PES packet can carry video, audio, private data and was originally used for some data streaming applications; this usage is now historical. Each MPEG-2 TS Packet is associated with one Transport Stream (TS) logical channel, which is identified by a 13 bit Packet ID (PID) carried in the MPEG-2 TS Packet header. The standard also defines a MPEG-2 control plane that may be used to transmit control information. For example, using System Information (SI) Tables (ETSI-SI, ETSI-SI1], or Program Specific Information (PSI) Tables. The Tables can be used to carry PID information about the transported stream. MPEG-2 address resolution assigns IP addresses to particular transmission multiplexes, and within a multiplex to a specific PID. The protocol signals this mapping to the other communicating devices (Gateways and Receivers). In some address resolution schemes, this address space is sub-divided into logical contexts known as Platforms or Sections. One use of this sub-division is to associate a separate context with each IP service provider that shares a common MPEG-2 TS (uses the same PID). MPEG-2 Receivers may optionally be assigned a Network Point of Attachment (NPA) to uniquely identify the L2 node within the MPEG-2 transmission network. An example of an NPA is the IEEE Medium Access Control (MAC) address. Where such addresses are used, these must also be signalled by the address resolution procedure. Finally, address resolution may need to signal the format of the data being transmitted. For example, the encapsulation used or any compression scheme that was used at the sender [ID-IPDVB-ARCH]. This document describes mechanisms to signal the TS Multiplex, the PID, and (if used) the MAC address or platform ID associated with each IP address or flow to the network layer at the sender and receiver. As will be seen below this can, for example, be implemented via descriptors sent in MPEG-2 SI tables (using the MPEG-2 control plane), via one or more new SI tables, or in-band by a protocol using a data channel similarly to the IPv4 Address Resolution Protocol, ARP, or IPv6 Neighbour Discovery (ND) protocol. Expires November 2004 [page 3] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 2. Conventions used in this document AIT: Application Information Table specified by the Multimedia Home Platform (MHP) specifications [ETSI-MHP]. This table may carry IPv4/IPv6 to MPEG-2 TS address resolution information. ATSC: Advanced Television Systems Committee [ATSC]. A set of framework and associated standards for the transmission of video, audio, and data, using the ISO MPEG-2 standard. DVB: Digital Video Broadcast [ETSI-DVB]. A set of framework and associated standards for the transmission of video, audio, and data, using the ISO MPEG-2 standard. DVB-RCS: Digital Video Broadcast Return Channel via Satellite. A bi-directional IPv4/IPv6 service employing low-cost Receivers. INT: Internet/MAC Notification Table. A uni-directional addressing resolution mechanism using SI and/or PSI Tables. MAC: Medium Access and Control of the Ethernet IEEE 802 standard of protocols (see also NPA). MHP: Multimedia Home Platform. An integrated MPEG-2 multimedia receiver, that may (in some cases) support IPv4/IPv6 services. MMT: Multicast Mapping Table (proprietary extension to DVB-RCS). MPE: Multiprotocol Encapsulation [ETSI-DAT, ETSI-DAT1]. A scheme that encapsulates Ethernet frames or IP Packets, creating a DSM-CC Section. The Section will be sent in a series of TS Packets over a TS Logical Channel. MPEG-2: A set of standards specified by the Motion Picture Experts Group (MPEG), and standardized by the International Standards Organisation (ISO) [ISO-MPEG]. NPA: Network Point of Attachment. Addresses primarily used for station (receiver) identification within a local network (e.g. IEEE MAC address). PES: Packetized Elementary Stream. A format of MPEG-2 TS packet payload usually used for video or audio information in MPEG-2 [ISO-MPEG]. Expires November 2004 [page 4] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 PID: Packet Identifier. A 13-bit field carried in the header of all MPEG-2 Transport Stream packets [ISO-MPEG]. This is used to identify the TS Logical Channel to which it belongs. PRIVATE SECTION: A syntactic structure used for mapping all service information (e.g. an SI table) into TS Packets. A table may be divided into a number of sections. All sections of a table must be carried over a single TS Logical Channel. PSI: Programme Specific Information: In this document, the term is used to describe any table used to convey information about a subset of services carried in a TS Multiplex (e.g. [ISO-MPEG]). PSI tables are carried in MPEG-2 private sections. SI TABLE: Service Information Table. In this document, the term is used to describe any table used to convey information about the service carried in a TS Multiplex (e.g. [ISO-MPEG]). SI tables are carried in MPEG-2 private sections. TS: Transport Stream [ISO-MPEG], a method of transmission at the MPEG-2 level using TS Packets; it represents level 2 of the ISO/OSI reference model. See also TS Logical Channel and TS Multiplex. TS LOGICAL CHANNEL: A channel identified at the MPEG-2 level; it represents level 2 of the ISO/OSI reference model. All packets sent over a channel carry the same PID value. TS MULTIPLEX: A set of MPEG-2 TS Logical Channels sent over a single common physical bearer (i.e. a link transmitting at a specified symbol rate, FEC setting, and transmission frequency). TS PACKET: A fixed-length 188B unit of data sent over an MPEG-2 multiplex [ISO-MPEG]; it corresponds to the cells, of e.g. ATM networks, and is frequently also referred to as a TS_cell. Each TS Packet carries a 4B header, plus optional overhead. Each TS packet carries a PID value to associate it with a single TS Logical Channel. Expires November 2004 [page 5] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 3. Address Resolution Requirements The IP address resolution support should support both existing IP over MPEG-2 encapsulations (e.g., MPE [ETSI-DAT, ETSI-DAT1]), and also any IETF encapsulation that may be defined [ID-IPDVB-ARCH]. <<< more requirements to be added >>> In some case, an MPEG-2 Transmission Network may support multiple IP networks. If this is the case, it is important to recognise the context (scope) within which an address is resolved, to prevent packets from one addressed scope leaking into other scopes. Examples of overlapping IP address assignments include: (i) Private unicast addresses (e.g. in IPv4, 10/8 prefix; 172.16/12 prefix; 192.168/16 prefix) should be confined to one addressed area. (ii) Some multicast addresses, (e.g., the scoped multicast addresses sometimes used in private networks). These are only valid within an addressed area (examples for IPv4 include; 239/8; 224.0.0/24; 224.0.1/24). Similar cases exist for some IPv6 multicast addresses. (iii) Scoped multicast addresses. Forwarding of these addresses is controlled by the scope associated with the address. IP packets with these addresses must not be allowed to travel outside their intended scope, and may cause unexpected behaviour if allowed to do so. In addition, overlapping address assignments can arise when using Level 2 Network Point of Attachment (NPA) addresses [ID-IPDVB- ARCH]: (i) The NPA address must be unique within the addressed area. IEEE MAC addresses used in Ethernet LANs are globally unique. If the NPA addresses are not globally unique, the same NPA address may be re-used by receivers in different addressed areas. (ii) The NPA broadcast address (all 1Ęs MAC address). Traffic with this address should be confined to one addressed area. (iii) Other non-IP protocols may also view sets of MAC multicast addresses as link-local, and may produce unexpected results if distributed across several private networks! 2.1 Unicast Support Reception of unicast packets destined for another addressed area may lead to an increase in the rate of received packets by systems connected via the network. IP end hosts normally filter received unicast IP packets based on their assigned IP address. Expires November 2004 [page 6] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 Reception of the additional network traffic may contribute to Processing load but should not lead to unexpected protocol behaviour. It does however introduce a potential Denial of Service (DoS) opportunity. When the Receiver acts as an IP router, the receipt of such packet may lead to unexpected protocol behaviour. This also provides a security vulnerability since arbitrary packets may be passed to the IP layer. 2.2 Multicast Support There are specific issues concerning IPv4 and IPv6 multicast over MPEG-2 Transmission Networks. (i) Mapping IP multicast groups to the underlying MPEG-2 TS Logical Channel (PID) and the MPEG-2 TS Multiplex. (ii) Provide signalling information to allow a receiver to locate an IP multicast flow within an MPEG-2 TS Multiplex. (iii) Determining group membership (e.g. utilising IGMP/MLD). Appropriate procedures need to be specified to identify the correct action when the same multicast group is available on separate TS Logical Channels. This could arise when different end hosts act as senders to contribute IP packets with the same IP group destination address. Another different case arises when a receiver may potentially receive more than one copy of the same packet. In some cases, these may be sent in different TS Logical Channels, or even different TS Multiplexes. In this case, at the IP level, the host/router may be unaware of this duplication. The primary goal of multicast support will be efficient filtering of IP-multicast packets by the receiver, and the mapping of IPv4 and IPv6 multicast addresses onto the associated PID value and TS Multiplex. The design should permit a large number of active multicast groups, and should minimise the processing load at the receiver when filtering and forwarding IP multicast packets. For example, schemes that may be easily implemented in hardware would be beneficial, since these may relieve the drivers and operating systems from discarding unwanted multicast traffic. Expires November 2004 [page 7] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 4. MPEG-2 Address Resolution Operation In this section, the MPEG-2 address resolution mechanisms are reviewed. In MPEG-2, the information about the set of MPEG-2 TS Logical Channels carried over a TS Multiplex is usually distributed via tables (service information, SI) sent using channels assigned a specific (well-known) set of PIDs. This system was originally designed for audio/video distribution. The design requires access to and processing of the SI table information [ETSI-SI, ETSI-SI1]. This scheme is complex, and reflects the complexity of delivering and co-ordinating the various TS Logical Channels associated with a multimedia TV programme. Because of its historical usage, there is no direct support for IP mechanisms for identification of the TS multiplex and PID in use for a particular IP address. It is also important to highlight that a PID value is associated with a unidirectional channel, also a result of its initial usage. 4.1 Static configuration. The static mapping option (IP addresses or flows statically mapped to PIDs) is the equivalent to signalling "out-of-band". The application programmer, installing engineer, or user receives the mapping via some outside means (not in the MPEG-2 TS). This is useful for testing, experimental networks, small subnetworks and closed domains. A single "well-known" PID is a specialisation of this, but requires all IP traffic to be placed into the specified TS logical channel. Section filtering may be used to differentiate subnetworks at the expense of added complexity and potential performance penalties. 4.2 Table-Based Address Resolution MPEG-2 associates multimedia MPEG information with PIDs, using MPEG-2 Tables. A TS multiplex may provide PID information for IP services by integrating additional information into the existing MPEG-2 tables, or to define additional tables specific to the IP service. This has a dual advantage: (i) IP specific information can be obtained directly. (ii) The mechanism uses an already standardised mechanism. A large number of methods exist within the standards and current implementations of systems for allowing a MPEG-2 receiver to identify the appropriate PID and multiplex using to transmit traffic to a specific IP address. Expires November 2004 [page 8] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 Examples include: (i) IP/MAC Notification Table (INT) in the DVB Data standard [ETS_DAT]. This provides uni-directional address resolution of IPv4/IPv6 multicast addresses to MPEG-2 TS. (ii) Application Information Table (AIT) in the Multimedia Home Platform (MHP) specifications [ETSI-MHP]. (iii) Multicast Mapping Table (MMT) an MPEG-2 Table employed by some DVB-RCS systems to provide uni-directional address resolution of IPv4 multicast addresses to MPEG-2 TS. (iv) >>> AuthorĘs Note: Please send details of experience using the above schemes (and any others) to authors. <<< The MMT and AIT are used for specific applications. The INT is DVB standardised and more general purpose. It supports both IPv4 and IPv6 and can be used in combination with the other tables. It is the favoured choice of some members of the DVB community for address management and is briefly described below. 4.2.1 Description of the IP/MAC Notification Table (INT) and its usage. The INT provides a mechanism for carrying information about the location of IP/MAC flows within DVB networks. An IP/MAC Platform represents a set of IP/MAC streams and/or receiver devices. Such a Platform may span several transport streams within one or multiple DVB networks and represents a single IP network with a harmonized address space (i.e. one without address conflicts). The IP/MAC Platform concept allows for the coexistence of several non- harmonized IP/MAC address spaces on the same DVB network. The INT allows "subnets" and fully specified single destination addresses to make signalling bandwidth efficient and flexible as required. The "subnet mask" (also for IPv6) can be given in full form or in slash notation (e.g. /127), this supports IPv6 prefixes. Multicast addresses can be given with or without source (address or range), although if source address is given then only the slash notation can be used for prefixes/subnets. Expires November 2004 [page 9] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 In addition to identification and security descriptors the following descriptors are used for address binding in INT tables: (i) target_MAC_address_descriptor: The descriptor used to describe a single or group of MAC addresses (and their mask). (ii) target_MAC_address_range_descriptor: May be used to setup filters. (iii) target_IP_address_descriptor: The descriptor describing a single or group of IPv4 unicast or multicast addresses (and their mask). (iv) target_IP_slash_descriptor: Allows definition and announcement of an IPv4 subnet. (v) target_IP_source_slash_descriptor: Uses source and destination addresses to target a single or group of devices; could be used to define flows. (vi) IP/MAC stream_location_descriptor: This descriptor directly locates the IP/MAC stream in a DVB network. The following descriptors provide corresponding functions for IPv6 addresses: target_IPv6_address_descriptor target_IPv6_slash_descriptor and target_IPv6_source_slash_descriptor In addition, the ISP_access_mode_descriptor allows definition if the access to the ISP is done via an alternative non-DVB network (hence another address is necessary). The INT provides a set of descriptors to manage addressing in a DVB network. Its drawbacks are that while the IP/MAC concept is general enough there is still a need to manage the addressing (and the traffic) at the PID level. It currently is defined only for Multi-Protocol Encapsulation (MPE) and would need extension to support other schemes. In addition the use of a centralized management prevents the implementation of a more dynamic scheme. 4.3 IP Address Resolution Protocol Another possible approach is to design a query/response protocol (similar to, or based on the neighbour advertisements of the IPv6 ND protocol), which operates over an MPEG-2 TS Logical Channel using a previously agreed PID (e.g. configured, or communicated using a SI table). Expires November 2004 [page 10] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 While the Neighbour Advertisement Protocol [RFC2461] could be used as a basis for such a design for IPv6 addresses, the extensive use of broadcast messages to request and transmit layer 2 addresses would prove inefficient for systems using a wireless physical layer. Both ARP and ND allow unsolicited advertisements of bindings by a sender that are broadcast/multicast to the network, without requiring the overhead of a client request. However, both ND and ARP are currently restricted to advertising a single association per message. To achieve efficient transmission and receiver processing over broadcast physical layer, a method needs to be found that advertises several associations in a single message (e.g., following the method used in MPEG-2 Tables). The development of IP_layer address resolution would have several merits, particularly for IP-only services and two-way MPEG-2 transmission networks. Not only would may release a Receiver from performing MPEG-2 table processing, it would also allow much more dynamic association of PIDs to traffic. Examples of dynamic associations include: association/freeing of PIDs in response to join or prune actions taken by multicast routing protocols, or on assignment of new IP addresses using DHCP/DHCPv6. Implementing such protocols above the IP layer (e.g. using multicast IP transport, as used by ND), would allow this protocol to be implemented in a portable way not dependent on specific receiver hardware/drivers and would allow future integration of the functions within IP routers. The nature of an MPEG-2 transport network and the need to maintain flexibility for the operator, means that a protocol would need to use operator specifics for address resolution. Adding to this complexity, 2-way MPEG-2 services (e.g. DVB-RCS) employ a pair of logically separate unidirectional TS, requiring separate return and forward resolution. No address resolution protocol has yet been defined for MPEG-2 transmission networks. 5. Conclusions and Recommendations In current MPEG-2 networks, the bindings between IP addresses and PIDs are usually either done statically (such as in the cable networks) or carried in tables such at the standard AIT in MHP and the IP Notification Tables (INT) of DVB. In addition, the DVB-RCS community has defined a Multicast Mapping Tables (MMT) to improve the efficiency of multicast address mappings in DVB-RCS networks. This brief document has reviewed the status of these current address resolution mechanisms in MPEG-2 networks to clearly define their usage and identify what would be needed to improve their conformity to standard IP practices. Expires November 2004 [page 11] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 Current limitations of the current methods include the dynamics of the table refresh support for IP scoping of addresses, and the lack of a universal and generic table access methodology. The authors recommend that standards track activity is needed in the IPDVB WG to define an IP-oriented alternative to allow link configuration of a ULE/MPE link above the IP layer. The specification and definition of address resolution mechanisms relating to MPEG-2 PID to/from IP address mapping function, QoS association and other mapping functions (e.g. parameters associated with a PID/Multiplex) could be supported using a table- based protocol to be extensible to ensure a wide applicability to different types of MPEG-2 networks and intended applications. It is expected to be possible to re-use existing protocol machinery. For example, XML schemas could be defined and used to fetch the required information from the tables. Because XML implements standard grammar and syntax this address resolution information would be common to all MPEG-2 networks. XML/SOAP protocol exchanges may be a suitable method to transfer the tables. 6. Security Considerations The normal security issues relating to the use of wireless links for transport Internet traffic should be considered. Readers are also referred to the known security issues associated with ARP RFC826] and ND. Consideration will be given to those methods that will ensure that usage of MPEG-2 network resources will be restricted to IP addresses that are not a threat to those resources or other resources in the Internet. 7. Acknowledgments The authors wish to thank Rod Walsh, Jun Takei, Alexander Adolf and the ipdvb WG members for their inputs. The authors would also like to acknowledge the support of the European Space Agency Expires November 2004 [page 12] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 8. References 8.1 Normative References [ATSC] A/53C, "ATSC Digital Television Standard", Advanced Television Systems Committee (ATSC), Doc. A/53C, 2004. [ATSC-DAT] A/90, "ATSC Data Broadcast Standard", Advanced Television Systems Committee (ATSC), Doc. A/090, 2000. [ATSC-DATG] A/91, "Recommended Practice: Implementation Guidelines for the ATSC Data Broadcast Standard", Advanced Television Systems Committee (ATSC),Doc. A/91, 2001. [ATSC-A92] A/92 "Delivery of IP Multicast Sessions over ATSC Data Broadcast", Advanced Television Systems Committee (ATSC), Doc. A/92, 2002. [ATSC-G] A/54A, "Guide to the use of the ATSC Digital Television Standard", Advanced Television Systems Committee (ATSC), Doc. A/54A, 2003. [ATSC-PSIP-TC] A/65B, "Program and System Information Protocol for Terrestrial Broadcast and Cable", Advanced Television Systems Committee (ATSC), Doc. A/65B, 2003. [ETSI-DAT] EN 301 192, "Specifications for Data Broadcasting", v1.3.1, European Telecommunications Standards Institute (ETSI), May 2003. http://www.etsi/org/ [ETSI-DAT1] EN 101 202, "Implementation Guide for Data", v1.2.1, European Telecommunications Standards Institute (ETSI), May 2003. http://www.etsi/org/ [ETSI-MHP] ETSI TS 101 812, "Digital Video Broadcasting (DVB); Multimedia Home Platform (MHP) Specification", v1.2.1, European Telecommunications Standards Institute (ETSI), June 2002. http://www.etsi/org/ [ETSI-SI] ETSI EN 300 468: "Digital Video Broadcasting (DVB); Specification for Service Information (SI) in DVB systems". [ETSI-SI1] ETSI TR 101 162: "Digital Video Broadcasting (DVB); Allocation of Service Information (SI) codes for DVB systems". [ID-IPDVB-ARCH] Montpetit, M.J., Fairhurst, G., Clausen, H.D., Collini-Nocker, B., and H. Linder, "Architecture for IP transport over MPEG-2 Networks", Internet Draft, draft-ipdvb-arch-00.txt, July 2004, Work in Progress, IPDVB WG. Expires November 2004 [page 13] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 [ID-MMUSIC-IMG] Y. Nomura, R. Walsh, J-P. Luoma, J. Ott, H. Schulzrinne, "Protocol Requirements for Internet Media Guides", nternet Draft, draft-ietf-mmusic-img-req-07.txt, June 2004, Work in Progress,MMUSIC WG. [ISO-DSMCC] ISO/IEC IS 13818-6 "Information technology -- Generic coding of moving pictures and associated audio information -- Part 6: Extensions for DSM-CC is a full software implementation", International Standards Organisation (ISO). [RFC826] Plummer, D. "An Ethernet Address Resolution Protocol", RFC 826, IETF, November 1982. [RFC1122] B. Braden, ed., "Requirements for Internet Hosts - Communication Layers", RFC 1122. [RFC1112] Deering, S.E., "Host Extensions for IP Multicasting", RFC1112, (STD05), IETF. August 1989. [RFC2461] Narten, T., Nordmark, E., and W. Simpson, "Neighbor Discovery for IP Version 6 (IPv6), RFC 2461, December 1998. [RFC2464] Crawford. M., "Transmission of IPv6 Packets over Ethernet Networks", RFC2464, IETF December 1998. 8.2 Informative References [ETSI-DAT] EN 301 192 Specifications for Data Broadcasting, European Telecommunications Standards Institute (ETSI). [ETSI-DVBC] EN 300 800 Digital Video Broadcasting (DVB); DVB interaction channel for Cable TV distribution systems (CATV), European Telecommunications Standards Institute (ETSI). [ISO-MPEG] ISO/IEC DIS 13818-1:2000 "Information technology ” Generic coding of moving pictures and associated audio information: Systems", International Standards Organisation (ISO). [ETSI-DAT] EN 301 192 Specifications for Data Broadcasting, European Telecommunications Standards Institute (ETSI). http://www.atsc.org/standards/Code_Point_Registry.pdf Expires November 2004 [page 14] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 9. Authors' Addresses Godred Fairhurst Department of Engineering University of Aberdeen Aberdeen, AB24 3UE UK Email: gorry@erg.abdn.ac.uk Web: http://www.erg.abdn.ac.uk/users/gorry Marie-Jose Montpetit MJMontpetit.com Email: marie@mjmontpetit.com 10. IPR Notices The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. 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. Expires November 2004 [page 15] INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2 networks July 2004 11. Copyright Statement Copyright (C) The Internet Society (2004). 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. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTORS, THE ORGANIZATIONS THEY REPRESENT OR ARE SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 12. IANA Considerations NOT KNOWN AT THIS TIME. Expires November 2004 [page 16]