IGMPv2 SSM Mapping

The PIM-SSM feature requires all IGMP hosts to send IGMPv3 reports. Where you have an IGMPv2 host, this can create a compatibility problem. In particular, the reports from an IGMPv2 host contain a group multicast address but do not contain source addresses. The IGMPv3 reports contain both the group multicast address and one or more source addresses. This feature converts IGMPv2 reports into IGMPv3 reports through use of the ip igmp ssm-map command and a properly configured ACL.

The ACL used with this feature filters for the group multicast address. The ACL is then associated with one or more source addresses using the ip igmp ssm-map command. When the ip igmp ssm-map enable command is configured, IGMPv3 reports are sent for IGMPv2 hosts.

The following sections describe how to configure the ACL and the ip igmp ssm-map command to use the IGMPv2 SSM mapping feature:

  • Configuring an ACL for IGMPv2 SSM mapping
  • Configuring the IGMPv2 SSM mapping commands
Note: IGMPv2 SSM mapping is not supported for IGMP static groups.

In this section:

  1. Configuring an ACL for IGMPv2 SSM Mapping
    You can use either a standard or extended ACL to identify the group multicast address(es) that you want to add source addresses to when creating an IGMPv2 SSM mapping.
  2. Configuring IGMPv2 SSM Mapping
    The ip ssm-map command is used to enable the IGMPv2 mapping feature and to define the maps between IGMPv2 group addresses and multicast source addresses.
  3. Displaying an IGMP SSM Mapping Information
Parent topic: IGMPv3