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   Internet Engineering Task Force                    Gorry Fairhurst
   Internet Draft                          University of Aberdeen, U.K.
   Document: draft-fair-ipdvb-ar-02.txt            Marie-Jose Montpetit
   October 2004                                    MJMontpetit.com, USA
                                                     Hidetaka Izumiyama
                                                         Wishnet, Japan
  
   Category: Informational                           Expires March 2005
  
   Address Resolution for IP datagrams over MPEG-2 networks
  
   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
   RFC 3668.
  
  
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   Copyright (C) The Internet Society (2004), All Rights Reserved
  
  
    Abstract
  
     This document describes the current mechanisms to bind IPv4/IPv6
     addresses and flows to MPEG-2 Transport Streams (TS). For MPEG-2
     systems to become true subnetworks of the general Internet,
     methods 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. In MPEG-2 networks, address resolution is a three level
     process: the IP address is resolved to a NPA/MAC address, then
     associated with a Packet ID (PID) and finally to a 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 their compliance
     to AR requirements established.
  
  
  
  
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   INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2
   networks  October 2004
  
  
  
   Table of Contents
  
        Document History
        1. Introduction
        2. Convention used in the document
        3. Address Resolution Requirement
        4. MPEG-2 Address Resolution Operation
        5. Mapping of IP addresses to NPA/MAC addresses
        6. Conclusions and Recommendations
        7. Security Considerations
        8. Acknowledgements
        9. References
        10. Author's Addresses
        11. IPR Notices
        12. Copyright Statements
        13. IANA Considerations
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
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   INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2
   networks  October 2004
  
  
  
  [RFC EDITOR NOTE: this section must be deleted prior to publication]
  
   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.
     -02 fairly important review; took out all new protocol references
         and moved to a configuration draft; added one author Hidetaka
         Izumiyama who has contributions on UDLR experiments;
         added a section on AR in UDLR; reworked the bibliography.
  
  
  
   [END OF RFC EDITOR NOTE]
  
   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).
  
  
  
  
  
  
  
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    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 current 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.
  
  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.
  
  
    Feed: A router or host that has send-only connectivity to a UDL.
  
  
    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.
  
  
  
  
  
  
  
  
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    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].
  
  
    Receiver (in the UDL context): A router or a host that has receive
    only connectivity to a UDL. A receiver may have connectivity via an
    alternate interface, allowing possible transmission on this second
    interface.
  
    UDL: Unidirectional link: A one-way transmission IP over DVB link,
    e.g., a broadcast satellite link.
  
    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.
  
  
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    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.
  
  
   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].
    AR requirements are summarized below:
    - Use of a table based approach to promote AR scaling.
    - Mechanisms to install AR information at the server (unsolicited
      registration).
    - Incremental table updates or purging of stale information.
    - Support to scoping.
    - Security associations to authenticate the AR information.
  
  
    In particular, 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.
  
  
  
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    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 1 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.
  
  
    3.1 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.
  
  
    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.
  
    3.2 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.
  
  
  
  
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    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.
  
   4. MPEG-2 Address Resolution Operations
  
    In this section, current 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.
  
  
  
  
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   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.
  
    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.
  
    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.
  
  
  
  
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    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.
  
    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.
  
  
  
  
  
  
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    4.2.2 Description of the Multicast Mapping Table and its usage
  
  
    The Multicast Mapping Table (MMT) is an example employing an MPEG-2
    level control table to communicate a set of multicast addresses and
    their associated PID value.  This table allows a DVB-RCS Forward
    Link Subsystem (FLSS) to specify the mapping and Return Channel
    Satellite Terminals (RCSTs) to determine the PID values are being
    used by the traffic that need to be received. The MMT is not
    currently a part of the DVB-RCS specification.
  
  
    4.2.3 Description of the Application Information Table and its usage
  
  
    The DVB Multimedia Home Platform (MHP) specification does not define
    a specific AR function. However, the MHP Standard specifies an
    Application Information Table (AIT) that each MHP Receiver monitors
    to receive a variety of control information. The AIT is a DSMCC
    format table that provides information about data broadcasts, the
    required activation state of applications carried by a broadcast
    stream, etc. This information allows the broadcaster to request that
    the receiver change the activation state of an application, and to
    direct applications to receive specific multicast packet flows
    (using IPv4 or IPv6 routing descriptors.  In MHP, AR is not seen as
    specific function, but a part of a wider configuration and control
    function.
  
  
    4.2.4 Comparison of table based approached and compliance to
          requirements
  
  
    All tables meet the specified requirements of the groups that
    created them and all have their strength:  the INT in terms of
    flexibility and extensibility, the MMT in its simplicity, the AIT in
    its extensibility. However, they exhibit scalability constraints,
    encourage the development of technology specific solutions and do
    not fully adopt IP-centric approaches that would enable easier use
    of the MPEG-2 bearer as a link technology within the wider Internet.
  
  
    <<< more specifics to be added later >>>
  
  
    5. Mapping of IP addresses to NPA/MAC addresses
  
  
    This section reviews the mechanisms to assign IP addresses to
    NPA/MAC addresses. This means millions of potential mappings and
    raises the issues of scaling. It is obvious that in this case the
    un-solicited distribution of addresses by tables that carry
    single mappings needs to be avoided.
    <<< specific examples to be added >>>
  
  
  
    5.1 Bi-directional case
    <<< To be added >>>
  
  
  
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    5.2 Uni-directional case
  
  
    This section introduces how to use UDLR link layer tunneling
    mechanisms to use ARP and ND on Uni-Directional DVB links
    and shows the results of the evaluation of the combinations
    of UDLR and various IP over DB encapsulation protocols.
  
  
    5.2.1 Issues
  
  
    In order to use ARP and ND on IP over a DVB link, there are 2
    issues that need to be considered. One is uni-directional
    functionality, and the other is the efficiency of encapsulation for
    IP over DVB transmission which is not AR related.
  
  
    The IP over DVB link is basically a Uni-Directional Link (UDL), so
    ARP and ND do not work as is, because these protocols assume the
    link to be bi-directional. The UDL receiver cannot send any response
    to a querier over the UDL link.
  
  
    In order to solve this, we propose to use the UDLR (RFC3077)
    link layer tunneling mechanism. UDLR emulates the UDL as a
    bi-directional broadcast type link at the datalink layer. The
    uni-directional functionality is hidden to IP and upper layer
    protocols.
  
    5.2.2 Evaluation
  
  
    (i)Candidate of IP over DVB encapsulation protocols
  
  
    In order to evaluate the functionality of ARP and ND on the IP over
    DVB with UDLR environment, we select major IP over DVB encapsulation
    protocols as candidates namely ULE and MPE.
  
  
                                        Field on Ethernet frame
                                  Total OH src mac dst mac type
                                  [bytes]
  
  
     a. ULE without dst MAC address    8        x     x      o
     b. ULE with dst MAC address      14        x     o      o
     c. MPE without LLC/SNAP          16        x     o      x
     d. MPE with LLC/SNAP             24        x     o      o
     e. ULE with Bridging extension
        (8+2+6+6 B)
     f. MPE+LLC/SNAP+Bridging
         (24+2+6+6)
  
  
    (ii)Results of evaluation
  
  
     a. ULE without dst MAC address
     << To be added>>
  
  
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     b. ULE with dst MAC address
     << To be added>>
  
  
     c. MPE without LLC/SNAP
  
  
    For IPv4, the ARP request packet cannot be transmitted
    on the UDL (for either feed or receiver query) because of
    the lack of Ethertype field. As result, the ARP protocol
    does not work on the UDL.
  
  
    ND works fine. Because ND uses ICMP6 on IPv6, the datalink
    Protocol does not need to carry non-IPv6 packets.
  
  
    It is worth noting that this is not an issue with the ULE
    encapsulation [ID-IPDVB-ULE].
  
  
     d. MPE with LLC/SNAP
  
  
    There is no specification to carry ARP packets using LLC/SNAP.
    However LLC effectively bridges therefore there is no need for
    a specific address.
  
  
    <<< others to be added when appropriate>>>
  
  
  
    5.2.3 Discussion
  
  
    (i)ULE
     <<To be added>>
  
  
    (ii)MPE
  
  
    The data link driver of Feed and Receiver must see the IP
    version field on the IP header to identify the IP version.
    There is no such field on the MPE header if LLC/SNAP is
    not used.
  
  
    << More discussions to be added >>>
  
  
  
    <<< Other real implementations requested: DHCP etc. >>>
  
  
  
  
  
  
  
  
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   INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2
   networks October 2004
  
  
   6. 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 allow to identify what would be needed to improve
    their conformity to standard IP practices.
  
  
    Current limitations of the current methods include the dynamics of
    the table refresh support for IP scoping of addresses, a generic
    access method for ARP and ND using the ULE encapsulation 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.
  
  
  
  
   7. 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.
  
   8. 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
  
  
  
  
  
  
  
  
  
  
  
  
  
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   INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2
   networks October 2004
  
   9. References
  
    9.1 Normative References
  
  
    [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).
  
  
  
    9.2 Informative 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".
  
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   INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2
   networks October 2004
  
  
    [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,
     October 2004, Work in Progress, IPDVB WG.
  
  
    [IP-IPDVB-ULE] Fairhurst, G., Collini-Nocker, B., and H. Linder,
    "Ultra Light Encapsulation", Internet Draft, draft-ipdvb-ule-02.txt,
     October 2004, Work in Progress, IPDVB WG.
  
  
  
    [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.
  
    [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.
  
  
  
   10. 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
  
  
        Hidetaka Izumiyama
        President CEO, Wishnet Inc.
        5-15-5-001 Shirokanedai, Minato-ku
        Tokyo, 108-0071, Japan
        Email: izu@wishnet.co.jp
  
  
  
  
  
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   INTERNET DRAFT Address Resolution for IP datagrams over MPEG-2
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   11. IPR Notices
  
  
    Intellectual Property Statement
  
  
    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.
  
  
  
  
    Disclaimer of Validity
  
  
   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS 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. 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.
  
  
   13. IANA Considerations
  
   NOT KNOWN AT THIS TIME.
  
  
  
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