IP Multicast: PIM Configuration Guide, Cisco IOS XE Release 3S (Cisco ASR 1000)
IPv6 Multicast: PIM Sparse Mode
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IPv6 Multicast: PIM Sparse Mode

Contents

IPv6 Multicast: PIM Sparse Mode

IPv6 multicast provides support for intradomain multicast routing using PIM sparse mode (PIM-SM). PIM-SM uses unicast routing to provide reverse-path information for multicast tree building, but it is not dependent on any particular unicast routing protocol.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Information About IPv6 Multicast PIM Sparse Mode

Protocol Independent Multicast

Protocol Independent Multicast (PIM) is used between devices so that they can track which multicast packets to forward to each other and to their directly connected LANs. PIM works independently of the unicast routing protocol to perform send or receive multicast route updates like other protocols. Regardless of which unicast routing protocols are being used in the LAN to populate the unicast routing table, Cisco IOS PIM uses the existing unicast table content to perform the Reverse Path Forwarding (RPF) check instead of building and maintaining its own separate routing table.

You can configure IPv6 multicast to use either a PIM- Sparse Mode (SM) or PIM-Source Specific Multicast (SSM) operation, or you can use both PIM-SM and PIM-SSM together in your network.

PIM-Sparse Mode

IPv6 multicast provides support for intradomain multicast routing using PIM-SM. PIM-SM uses unicast routing to provide reverse-path information for multicast tree building, but it is not dependent on any particular unicast routing protocol.

PIM-SM is used in a multicast network when relatively few devices are involved in each multicast and these devices do not forward multicast packets for a group, unless there is an explicit request for the traffic. PIM-SM distributes information about active sources by forwarding data packets on the shared tree. PIM-SM initially uses shared trees, which requires the use of an RP.

Requests are accomplished via PIM joins, which are sent hop by hop toward the root node of the tree. The root node of a tree in PIM-SM is the RP in the case of a shared tree or the first-hop device that is directly connected to the multicast source in the case of a shortest path tree (SPT). The RP keeps track of multicast groups and the hosts that send multicast packets are registered with the RP by that host’s first-hop device.

As a PIM join travels up the tree, devices along the path set up multicast forwarding state so that the requested multicast traffic will be forwarded back down the tree. When multicast traffic is no longer needed, a device sends a PIM prune up the tree toward the root node to prune (or remove) the unnecessary traffic. As this PIM prune travels hop by hop up the tree, each device updates its forwarding state appropriately. Ultimately, the forwarding state associated with a multicast group or source is removed.

A multicast data sender sends data destined for a multicast group. The designated router (DR) of the sender takes those data packets, unicast-encapsulates them, and sends them directly to the RP. The RP receives these encapsulated data packets, de-encapsulates them, and forwards them onto the shared tree. The packets then follow the (*, G) multicast tree state in the devices on the RP tree, being replicated wherever the RP tree branches, and eventually reaching all the receivers for that multicast group. The process of encapsulating data packets to the RP is called registering, and the encapsulation packets are called PIM register packets.

Designated Router

Cisco devices use PIM-SM to forward multicast traffic and follow an election process to select a designated device when there is more than one device on a LAN segment.

The designated router (DR) is responsible for sending PIM register and PIM join and prune messages toward the RP to inform it about active sources and host group membership.

If there are multiple PIM-SM devices on a LAN, a DR must be elected to avoid duplicating multicast traffic for connected hosts. The PIM device with the highest IPv6 address becomes the DR for the LAN unless you choose to force the DR election by use of the ipv6 pim dr-priority command. This command allows you to specify the DR priority of each device on the LAN segment (default priority = 1) so that the device with the highest priority will be elected as the DR. If all devices on the LAN segment have the same priority, then the highest IPv6 address is again used as the tiebreaker.

The figure below illustrates what happens on a multiaccess segment. Device A and Device B are connected to a common multiaccess Ethernet segment with Host A as an active receiver for Group A. Only Device A, operating as the DR, sends joins to the RP to construct the shared tree for Group A. If Device B was also permitted to send (*, G) joins to the RP, parallel paths would be created and Host A would receive duplicate multicast traffic. Once Host A begins to source multicast traffic to the group, the DR’s responsibility is to send register messages to the RP. If both devices were assigned the responsibility, the RP would receive duplicate multicast packets.

Figure 1. Designated Router Election on a Multiaccess Segment

If the DR should fail, the PIM-SM provides a way to detect the failure of Device A and elect a failover DR. If the DR (Device A) became inoperable, Device B would detect this situation when its neighbor adjacency with Device A timed out. Because Device B has been hearing MLD membership reports from Host A, it already has MLD state for Group A on this interface and would immediately send a join to the RP when it became the new DR. This step reestablishes traffic flow down a new branch of the shared tree via Device B. Additionally, if Host A were sourcing traffic, Device B would initiate a new register process immediately after receiving the next multicast packet from Host A. This action would trigger the RP to join the SPT to Host A via a new branch through Device B.


Tip


Two PIM devices are neighbors if there is a direct connection between them. To display your PIM neighbors, use the show ipv6 pim neighbor command in privileged EXEC mode.



Note


The DR election process is required only on multiaccess LANs.


Rendezvous Point

IPv6 PIM provides embedded RP support. Embedded RP support allows the device to learn RP information using the multicast group destination address instead of the statically configured RP. For devices that are the RP, the device must be statically configured as the RP.

The device searches for embedded RP group addresses in MLD reports or PIM messages and data packets. On finding such an address, the device learns the RP for the group from the address itself. It then uses this learned RP for all protocol activity for the group. For devices that are the RP, the device is advertised as an embedded RP must be configured as the RP.

To select a static RP over an embedded RP, the specific embedded RP group range or mask must be configured in the access list of the static RP. When PIM is configured in sparse mode, you must also choose one or more devices to operate as an RP. An RP is a single common root placed at a chosen point of a shared distribution tree and is configured statically in each box.

PIM DRs forward data from directly connected multicast sources to the RP for distribution down the shared tree. Data is forwarded to the RP in one of two ways:

  • Data is encapsulated in register packets and unicast directly to the RP by the first-hop device operating as the DR.
  • If the RP has itself joined the source tree, it is multicast-forwarded per the RPF forwarding algorithm described in the PIM-Sparse Mode section.

The RP address is used by first-hop devices to send PIM register messages on behalf of a host sending a packet to the group. The RP address is also used by last-hop devices to send PIM join and prune messages to the RP to inform it about group membership. You must configure the RP address on all devices (including the RP device).

A PIM device can be an RP for more than one group. Only one RP address can be used at a time within a PIM domain for a certain group. The conditions specified by the access list determine for which groups the device is an RP.

IPv6 multicast supports the PIM accept register feature, which is the ability to perform PIM-SM register message filtering at the RP. The user can match an access list or compare the AS path for the registered source with the AS path specified in a route map.

PIM Shared Tree and Source Tree (Shortest-Path Tree)

By default, members of a group receive data from senders to the group across a single data distribution tree rooted at the RP. This type of distribution tree is called shared tree or rendezvous point tree (RPT), as illustrated in the figure below. Data from senders is delivered to the RP for distribution to group members joined to the shared tree.

Figure 2. Shared Tree and Source Tree (Shortest Path Tree)

If the data threshold warrants, leaf devices on the shared tree may initiate a switch to the data distribution tree rooted at the source. This type of distribution tree is called a shortest path tree or source tree. By default, the software switches to a source tree upon receiving the first data packet from a source.

The following process details the move from shared tree to source tree:

  1. Receiver joins a group; leaf Device C sends a join message toward the RP.
  2. RP puts the link to Device C in its outgoing interface list.
  3. Source sends the data; Device A encapsulates the data in the register and sends it to the RP.
  4. RP forwards the data down the shared tree to Device C and sends a join message toward the source. At this point, data may arrive twice at Device C, once encapsulated and once natively.
  5. When data arrives natively (unencapsulated) at the RP, the RP sends a register-stop message to Device A.
  6. By default, receipt of the first data packet prompts Device C to send a join message toward the source.
  7. When Device C receives data on (S, G), it sends a prune message for the source up the shared tree.
  8. RP deletes the link to Device C from the outgoing interface of (S, G).
  9. RP triggers a prune message toward the source.

Join and prune messages are sent for sources and RPs. They are sent hop-by-hop and are processed by each PIM device along the path to the source or RP. Register and register-stop messages are not sent hop-by-hop. They are sent by the designated router (DR) that is directly connected to a source and are received by the RP for the group.

Reverse Path Forwarding

Reverse-path forwarding is used for forwarding multicast datagrams. It functions as follows:

  • If a device receives a datagram on an interface it uses to send unicast packets to the source, the packet has arrived on the RPF interface.
  • If the packet arrives on the RPF interface, a device forwards the packet out the interfaces present in the outgoing interface list of a multicast routing table entry.
  • If the packet does not arrive on the RPF interface, the packet is silently discarded to prevent loops.

PIM uses both source trees and RP-rooted shared trees to forward datagrams; the RPF check is performed differently for each, as follows:

  • If a PIM device has source-tree state (that is, an (S, G) entry is present in the multicast routing table), the device performs the RPF check against the IPv6 address of the source of the multicast packet.
  • If a PIM device has shared-tree state (and no explicit source-tree state), it performs the RPF check on the RP’s address (which is known when members join the group).

Sparse-mode PIM uses the RPF lookup function to determine where it needs to send joins and prunes. (S, G) joins (which are source-tree states) are sent toward the source. (*, G) joins (which are shared-tree states) are sent toward the RP.

How to Configure IPv6 Multicast PIM Sparse Mode

Enabling IPv6 Multicast Routing

IPv6 multicast uses MLD version 2. This version of MLD is fully backward-compatible with MLD version 1 (described in RFC 2710). Hosts that support only MLD version 1 will interoperate with a device running MLD version 2. Mixed LANs with both MLD version 1 and MLD version 2 hosts are likewise supported.

Before You Begin

You must first enable IPv6 unicast routing on all interfaces of the device on which you want to enable IPv6 multicast routing .

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ipv6 multicast-routing [vrf vrf-name]


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Device> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.
     
    Step 2 configure terminal


    Example:
    Device# configure terminal
     

    Enters global configuration mode.

     
    Step 3 ipv6 multicast-routing [vrf vrf-name]


    Example:
    Device(config)# ipv6 multicast-routing
     

    Enables multicast routing on all IPv6-enabled interfaces and enables multicast forwarding for PIM and MLD on all enabled interfaces of the device.

    • IPv6 multicast routing is disabled by default when IPv6 unicast routing is enabled. On certain devices, the IPv6 multicast routing must also be enabled in order to use IPv6 unicast routing.
     

    Configuring PIM-SM and Displaying PIM-SM Information for a Group Range

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    ipv6 pim [vrf vrf-name] rp-address ipv6-address [group-access-list] [bidir]

      4.    end

      5.    show ipv6 pim [vrf vrf-name] interface [state-on] [state-off] [type number]

      6.    show ipv6 pim [vrf vrf-name] group-map [group-name | group-address] | [group-range | group-mask] [info-source {bsr | default | embedded-rp | static}]

      7.    show ipv6 pim [vrf vrf-name] neighbor [detail] [interface-type interface-number | count]

      8.    show ipv6 pim [vrf vrf-name] range-list[config] [rp-address | rp-name]

      9.    show ipv6 pim [vrf vrf-name] tunnel [interface-type interface-number]

      10.    debug ipv6 pim [group-name | group-address | interface interface-type | bsr | group | mvpn | neighbor]


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Device> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.
       
      Step 2 configure terminal


      Example:
      Device# configure terminal
       

      Enters global configuration mode.

       
      Step 3 ipv6 pim [vrf vrf-name] rp-address ipv6-address [group-access-list] [bidir]


      Example:
      Device(config)# ipv6 pim rp-address 2001:DB8::01:800:200E:8C6C acc-grp-1
       

      Configures the address of a PIM RP for a particular group range.

       
      Step 4 end


      Example:
      Device(config-if)# end
       

      Returns to privileged EXEC mode.

       
      Step 5 show ipv6 pim [vrf vrf-name] interface [state-on] [state-off] [type number]


      Example:
      Device# show ipv6 pim interface
       

      Displays information about interfaces configured for PIM.

       
      Step 6 show ipv6 pim [vrf vrf-name] group-map [group-name | group-address] | [group-range | group-mask] [info-source {bsr | default | embedded-rp | static}]


      Example:
      Device# show ipv6 pim group-map
       

      Displays an IPv6 multicast group mapping table.

       
      Step 7 show ipv6 pim [vrf vrf-name] neighbor [detail] [interface-type interface-number | count]


      Example:
      Device# show ipv6 pim neighbor
       

      Displays the PIM neighbors discovered by the Cisco IOS software.

       
      Step 8 show ipv6 pim [vrf vrf-name] range-list[config] [rp-address | rp-name]


      Example:
      Device# show ipv6 pim range-list
       

      Displays information about IPv6 multicast range lists.

       
      Step 9 show ipv6 pim [vrf vrf-name] tunnel [interface-type interface-number]


      Example:
      Device# show ipv6 pim tunnel
       

      Displays information about the PIM register encapsulation and de-encapsulation tunnels on an interface.

       
      Step 10 debug ipv6 pim [group-name | group-address | interface interface-type | bsr | group | mvpn | neighbor]


      Example:
      Device# debug ipv6 pim
       

      Enables debugging on PIM protocol activity.

       

      Configuring PIM Options

      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    ipv6 pim [vrf vrf-name] spt-threshold infinity [group-list access-list-name]

        4.    ipv6 pim [vrf vrf-name] accept-register {list access-list | route-map map-name}

        5.    interface type number

        6.    ipv6 pim dr-priority value

        7.    ipv6 pim hello-interval seconds

        8.    ipv6 pim join-prune-interval seconds

        9.    exit

        10.    show ipv6 pim [vrf vrf-name] join-prune statistic [interface-type]


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example:
        Device> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.
         
        Step 2 configure terminal


        Example:
        Device# configure terminal
         

        Enters global configuration mode.

         
        Step 3 ipv6 pim [vrf vrf-name] spt-threshold infinity [group-list access-list-name]


        Example:
        Device(config)# ipv6 pim spt-threshold infinity group-list acc-grp-1
         

        Configures when a PIM leaf device joins the SPT for the specified groups.

         
        Step 4 ipv6 pim [vrf vrf-name] accept-register {list access-list | route-map map-name}


        Example:
        Device(config)# ipv6 pim accept-register route-map reg-filter
         

        Accepts or rejects registers at the RP.

         
        Step 5 interface type number


        Example:
        Device(config)# interface FastEthernet 1/0
         

        Specifies an interface type and number, and places the device in interface configuration mode.

         
        Step 6 ipv6 pim dr-priority value


        Example:
        Device(config-if)# ipv6 pim dr-priority 3
         

        Configures the DR priority on a PIM device.

         
        Step 7 ipv6 pim hello-interval seconds


        Example:
        Device(config-if)# ipv6 pim hello-interval 45
         

        Configures the frequency of PIM hello messages on an interface.

         
        Step 8 ipv6 pim join-prune-interval seconds


        Example:
        Device(config-if)# ipv6 pim join-prune-interval 75
         

        Configures periodic join and prune announcement intervals for a specified interface.

         
        Step 9 exit


        Example:
        Device(config-if)# exit
         

        Enter this command twice to exit interface configuration mode and enter privileged EXEC mode.

         
        Step 10 show ipv6 pim [vrf vrf-name] join-prune statistic [interface-type]


        Example:
        Device# show ipv6 pim join-prune statistic
         

        Displays the average join-prune aggregation for the most recently aggregated packets for each interface.

         

        Resetting the PIM Traffic Counters

        If PIM malfunctions, or in order to verify that the expected number of PIM packets are received and sent, clear PIM traffic counters. Once the traffic counters are cleared, you can verify that PIM is functioning correctly and that PIM packets are being received and sent correctly.

        SUMMARY STEPS

          1.    enable

          2.    clear ipv6 pim [vrf vrf-name] traffic

          3.    show ipv6 pim [vrf vrf-name] traffic


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 enable


          Example:
          Device> enable
           

          Enables privileged EXEC mode.

          • Enter your password if prompted.
           
          Step 2 clear ipv6 pim [vrf vrf-name] traffic


          Example:
          Device# clear ipv6 pim traffic
           

          Resets the PIM traffic counters.

           
          Step 3 show ipv6 pim [vrf vrf-name] traffic


          Example:
          Device# show ipv6 pim traffic
           

          Displays the PIM traffic counters.

           

          Turning Off IPv6 PIM on a Specified Interface

          A user might want only specified interfaces to perform IPv6 multicast and will therefore want to turn off PIM on a specified interface.

          SUMMARY STEPS

            1.    enable

            2.    configure terminal

            3.    interface type number

            4.    no ipv6 pim


          DETAILED STEPS
             Command or ActionPurpose
            Step 1 enable


            Example:
            Device> enable
             

            Enables privileged EXEC mode.

            • Enter your password if prompted.
             
            Step 2 configure terminal


            Example:
            Device# configure terminal
             

            Enters global configuration mode.

             
            Step 3 interface type number


            Example:
            Device(config)# interface FastEthernet 1/0
             

            Specifies an interface type and number, and places the device in interface configuration mode.

             
            Step 4 no ipv6 pim


            Example:
            Device(config-if)# no ipv6 pim
             

            Turns off IPv6 PIM on a specified interface.

             

            Configuration Examples for IPv6 Multicast PIM Sparse Mode

            Example: Enabling IPv6 Multicast Routing

            The following example enables multicast routing on all interfaces and also enables multicast forwarding for PIM and MLD on all enabled interfaces of the device.

            Device> enable
            Device# configure terminal
            Device(config)# ipv6 multicast-routing
            

            Example: Configuring PIM

            The following example shows how to configure a device to use PIM-SM using 2001:DB8::1 as the RP. It sets the SPT threshold to infinity to prevent switchover to the source tree when a source starts sending traffic and sets a filter on all sources that do not have a local multicast BGP prefix.

            Device(config)# ipv6 multicast-routing
            Device(config)# ipv6 pim rp-address 2001:DB8::1
            Device(config)# ipv6 pim spt-threshold infinity
            Device(config)# ipv6 pim accept-register route-map reg-filter
            

            Example: Displaying IPv6 PIM Topology Information

            Device# show ipv6 pim topology
            
            IP PIM Multicast Topology Table
            Entry state:(*/S,G)[RPT/SPT] Protocol Uptime Info
            Entry flags:KAT - Keep Alive Timer, AA - Assume Alive, PA - Probe Alive,
                RA - Really Alive, LH - Last Hop, DSS - Don't Signal Sources,
                RR - Register Received, SR - Sending Registers, E - MSDP External,
                DCC - Don't Check Connected
            Interface state:Name, Uptime, Fwd, Info
            Interface flags:LI - Local Interest, LD - Local Dissinterest,
            II - Internal Interest, ID - Internal Dissinterest,
            LH - Last Hop, AS - Assert, AB - Admin Boundary
            
            (*,FF05::1)
            SM UP:02:26:56 JP:Join(now) Flags:LH 
            RP:2001:DB8:1:1:2
            RPF:Ethernet1/1,FE81::1 
              Ethernet0/1          02:26:56  fwd LI LH 
            
            (2001:DB8:1:1:200,FF05::1)
            SM UP:00:00:07 JP:Null(never) Flags:
            RPF:Ethernet1/1,FE80::30:1:4 
              Ethernet1/1          00:00:07  off LI 

            Example: Displaying PIM-SM Information for a Group Range

            This example displays information about interfaces configured for PIM:

            Device# show ipv6 pim interface state-on
            
            Interface          PIM  Nbr   Hello  DR
                                    Count Intvl  Prior
            
            Ethernet0          on   0     30     1     
                Address:FE80::208:20FF:FE08:D7FF
                DR     :this system
            POS1/0             on   0     30     1     
                Address:FE80::208:20FF:FE08:D554
                DR     :this system
            POS4/0             on   1     30   1     
                Address:FE80::208:20FF:FE08:D554
                DR     :FE80::250:E2FF:FE8B:4C80
            POS4/1             on   0     30   1     
                Address:FE80::208:20FF:FE08:D554
                DR     :this system
            Loopback0          on   0     30     1     
                Address:FE80::208:20FF:FE08:D554
                DR     :this system

            This example displays an IPv6 multicast group mapping table:

            Device# show ipv6 pim group-map
            
            FF33::/32*
                  SSM
                  Info source:Static
                  Uptime:00:08:32, Groups:0
              FF34::/32*
                  SSM
                  Info source:Static
                  Uptime:00:09:42, Groups:0

            This example displays information about IPv6 multicast range lists:

            Device# show ipv6 pim range-list
            
            config SSM Exp:never Learnt from :::
             FF33::/32 Up:00:26:33
             FF34::/32 Up:00:26:33
             FF35::/32 Up:00:26:33
             FF36::/32 Up:00:26:33
             FF37::/32 Up:00:26:33
             FF38::/32 Up:00:26:33
             FF39::/32 Up:00:26:33
             FF3A::/32 Up:00:26:33
             FF3B::/32 Up:00:26:33
             FF3C::/32 Up:00:26:33
             FF3D::/32 Up:00:26:33
             FF3E::/32 Up:00:26:33
             FF3F::/32 Up:00:26:33
            config SM RP:40::1:1:1 Exp:never Learnt from :::
             FF13::/64 Up:00:03:50
            config SM RP:40::1:1:3 Exp:never Learnt from :::
             FF09::/64 Up:00:03:50

            Example: Configuring PIM Options

            The following example sets the DR priority, the PIM hello interval, and the periodic join and prune announcement interval on Ethernet interface 0/0.

            Device(config)# interface Ethernet0/0
            Device(config)# ipv6 pim hello-interval 60
            Device(config)# ipv6 pim dr-priority 3
            

            Example: Displaying Information About PIM Traffic

            Device# show ipv6 pim traffic 
            
            PIM Traffic Counters
            Elapsed time since counters cleared:00:05:29
            
                                          Received     Sent
            Valid PIM Packets               22          22        
            Hello                           22          22        
            Join-Prune                      0           0         
            Register                        0           0         
            Register Stop                   0           0         
            Assert                          0           0         
            Bidir DF Election               0           0         
            
            Errors:
            Malformed Packets                           0         
            Bad Checksums                               0         
            Send Errors                                 0         
            Packet Sent on Loopback Errors              0         
            Packets Received on PIM-disabled Interface  0         
            Packets Received with Unknown PIM Version   0 

            Additional References

            Related Documents

            Related Topic

            Document Title

            IPv6 addressing and connectivity

            IPv6 Configuration Guide

            Cisco IOS commands

            Cisco IOS Master Commands List, All Releases

            IP multicast commands

            Cisco IOS IP Multicast Command Reference

            IPv6 commands

            Cisco IOS IPv6 Command Reference

            Cisco IOS IPv6 features

            Cisco IOS IPv6 Feature Mapping

            Standards and RFCs

            Standard/RFC

            Title

            RFCs for IPv6

            IPv6 RFCs

            MIBs

            MIB

            MIBs Link

            To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

            http:/​/​www.cisco.com/​go/​mibs

            Technical Assistance

            Description

            Link

            The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

            http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

            Feature Information for IPv6 Multicast PIM Sparse Mode

            Table 1 Feature Information for IPv6 Multicast: PIM Sparse Mode

            Feature Name

            Releases

            Feature Information

            IPv6 Multicast: PIM Accept Register

            12.0(26)S

            12.3(4)T

            12.2(25)S

            12.2(25)SG

            12.2(33)SRA

            12.2(33)SXH

            12.4

            12.4(2)T

            Cisco IOS XE Release 2.1

            15.0(1)S

            The PIM accept register feature is the ability to perform PIM-SM register message filtering at the RP.

            The following commands were introduced or modified: ipv6 pim accept-register.

            IPv6 Multicast: PIM Embedded RP Support

            12.3(4)T

            12.4

            12.2(40)SG

            15.0(2)SG

            12.2(33)SRA

            12.2(33)SXH

            Embedded RP support allows the router to learn RP information using the multicast group destination address instead of the statically configured RP.

            The following commands were introduced or modified: ipv6 pim, ipv6 pim rp embedded.

            IPv6 Multicast: PIM Sparse Mode

            12.0(26)S

            12.2(18)S

            12.2(25)SG

            12.2(33)SRA

            12.3(2)T

            12.4

            12.4(2)T

            Cisco IOS XE Release 2.4

            15.0(1)S

            PIM-SM uses unicast routing to provide reverse-path information for multicast tree building. PIM-SM is used in a multicast network when relatively few routers are involved in each multicast and these routers do not forward multicast packets for a group, unless there is an explicit request for the traffic.

            The following commands were introduced or modified: clear ipv6 pim topology, debug ipv6 pim, debug ipv6 pim neighbor, ipv6 pim, ipv6 pim dr-priority, ipv6 pim hello-interval, ipv6 pim rp-address , ipv6 pim spt-threshold infinity, show ipv6 mroute, show ipv6 pim group-map, show ipv6 pim interface, show ipv6 pim neighbor, show ipv6 pim range-list, show ipv6 pim topology, show ipv6 pim tunnel.