Transmission of multicast traffic using PIM and IGMP protocols

Kaspersky SD-WAN supports transmission of multicast traffic between CPE devices and external network devices using the PIM and IGMP protocols. You can specify the basic settings of the PIM protocol on CPE devices, for example, the rendezvous points to be used, and then create multicast interfaces for interaction with other CPE devices. The created network interfaces are used as multicast interfaces.

If PIM connectivity is established between CPE devices and rendezvous points are defined for these devices, multicast interfaces can receive IGMP requests from clients over IGMP. IGMP requests contain IP addresses of sources from which clients want to receive multicast traffic packets. When sources send multicast packets to a rendezvous point, clients receive these multicast traffic packets.

If necessary, you can use the PIM protocol to connect CPE devices to external routers. To do so, you must enable the PIM protocol on the mulitcast interface to which the external router is connected.

Basic PIM settings

You can specify basic PIM settings in a CPE template or on the CPE device. Basic PIM settings specified in the CPE template are automatically propagated to all CPE devices that use this CPE template.

To modify the basic PIM settings:

1. Specify basic PIM settings in one of the following ways:
   • If you want to edit the basic PIM settings in a CPE template, go to the SD-WAN → CPE templates menu section, click the CPE template, and select the Multicast tab.
   • If you want to edit the basic PIM settings on a CPE device, go to the SD-WAN → CPE menu section, click the CPE device, and select the Multicast tab.

   By default, the General settings tab is selected, which displays the basic PIM settings.

2. In the Multicast drop-down list, select Enabled. The default value is Disabled.
3. Specify the rendezvous point for multicast traffic packet sources and clients that are connected to the CPE device:
   1. Under RP IP, click + Add and enter the IPv4 address of the rendezvous point.
   2. If you want to specify a multicast group associated with the rendezvous point, under RP group, enter the IPv4 prefix of your multicast group. Each rendezvous point can be associated with a dedicated multicast group.

   The rendezvous point is specified and displayed in the RP IP and RP group sections. You can specify multiple rendezvous points or delete rendezvous points. To delete a rendezvous point, click the delete icon next to it.

4. In the RP keepalive timer (sec.) field, enter the lifetime in seconds of traffic streams between the source and the multicast group (S,G). The countdown is reset if the CPE device receives a register packet. Range of values: 31 to 60,000. Default value: 185.
5. If you want to filter multicast traffic packets with the specified source IPv4 addresses on the CPE device, in the PIM register accept list drop-down list, select a created prefix list.
6. If a CPE device is on the last hop and you want to prevent this CPE device from switching over from the shared tree to the shortest path tree (SPT) when transmitting multicast traffic packets:
   1. Select the SPT switchover check box. This check box is cleared by default.
   2. If you want to deny or allow switchover from the Rendezvous Point Tree (RPT) to the shortest path tree when transmitting traffic packets from multicast groups with specified source IPv4 prefixes, select a created prefix list in the SPT prefix list drop-down list. Whether switchover is denied or allowed is determined as follows:
      • If the prefix list allows the IPv4 prefix, switchover does not occur.
      • If the prefix list denies the IPv4 prefix, switchover does occur.
7. If you want to perform ECMP balancing on a CPE device to distribute multicast traffic streams over multiple routes:
   1. Select the ECMP check box. This check box is cleared by default. For ECMP balancing, multiple routes must exist. If ECMP balancing is disabled, traffic is transmitted along one route.
   2. If you want to balance all traffic among the remaining routes in case one of the multicast interfaces fails, select the ECMP rebalance check box. The check box is cleared by default, and if one of the multicast interfaces fails, only the traffic that was transmitted through that multicast interface is redistributed.
8. In the PIM join/prune interval (sec.) field, enter the time interval in seconds for multicast interfaces to send join/prune packets to PIM peers. Range of values: 60 to 600. Default value: 60.
9. In the PIM keepalive timer (sec.) field, enter the lifetime in seconds of traffic streams between the source and the multicast group (S,G). The countdown is reset if the CPE device receives a join/prune packet. Range of values: 31 to 60,000. Default value: 210.
10. If you want to have the CPE device relay traffic packets with specified source IPv4 prefixes from multicast groups upon request from the client (Source Specific Multicast; SSM), in the SSM prefix list drop-down list, select a created prefix list.
11. In the RPF lookup mode drop-down list, select a Reverse Path Forwarding (RPF) lookup mode on the CPE device:
    • longer-prefix
    • lower-distance
    • mrib-only
    • mrib-then-urib. This is the default setting.
    • urib-only
12. If you want to add a static IPv4 route to the multicast routing table of the CPE device:
    1. Under Static multicast routes, click + Add.
    2. In the IP destination field, enter the destination IPv4 address of the static route.
    3. In the Type drop-down list, select the source type of the static route:
       • Address is an IPv4 address. If you select this value, in the Nexthop field, enter the source IPv4 address and prefix of the static route.
       • Interface is the created network interface. If you select this value, from the Nexthop drop-down list, select the source network interface of the static route.
    4. If necessary, in the Distance field, enter the metric of the static route. Range of values: 1 to 255.

    The static route is added and displayed under Static multicast routes. You can add multiple static routes or delete static routes. To delete a static route, click the delete icon next to it.

13. In the upper part of the settings area, click Save to save the settings of the CPE template or CPE device.

Managing multicast interfaces

You can view the table of multicast interfaces in a CPE template and on a CPE device:

• To display the table of multicast interfaces in a CPE template, go to the SD-WAN → CPE templates menu section, click the CPE template, and select the Multicast → Interfaces tab.
• To display the table of multicast interfaces on a CPE device, go to the SD-WAN → CPE menu section, click the CPE device, and select the Multicast → Interfaces tab.

Information about multicast interfaces is displayed in the following columns of the table:

• Network interface is the network interface used as a multicast interface.
• PIM indicates whether the exchange of messages with peers via the PIM protocol is enabled on the multicast interface:
  • Enabled
  • Disabled
• IGMP indicates whether the exchange of messages with peers via the IGMP protocol is enabled on the multicast interface:
  • Enabled
  • Disabled
• DR priority is the priority of the multicast interface. The highest-priority multicast interface becomes the designated router of the LAN segment. The greater the value, the higher the priority of the multicast interface.
• Inherited indicates whether the multicast interface is inherited from CPE template:
  • Yes
  • No

  This column is displayed only on the CPE device.

• Management contains the actions that can be performed with the multicast interface.

Creating a multicast interface

You can create a multicast interface in a CPE template or on an individual device. A multicast interface created in the CPE template is automatically created on all CPE devices that use this CPE template.

To create a multicast interface:

1. Create a multicast interface in one of the following ways:
   • If you want to create a multicast interface in a CPE template, go to the SD-WAN → CPE templates menu section, click the CPE template, and select the Multicast → Interfaces tab.
   • If you want to create a multicast interface on a CPE device, go to the SD-WAN → CPE menu section, click the CPE device, select the Multicast → Interfaces tab, and select the Override check box.

   A table of multicast interfaces is displayed.

2. Click + Multicast interface.
3. This opens a window, in that window, in the Network interface drop-down list, select a created network interface which you want to use as a multicast interface.
4. Configure the PIM protocol on the multicast interface:
   1. In the PIM drop-down list, select Enabled. The default value is Disabled.
   2. If you want to switch the multicast interface to passive mode, select the Passive check box. In passive mode, multicast interfaces do not exchange control packets. This check box is cleared by default.
   3. If you want to prohibit the exchange of bootstrap packets on the multicast interface, clear the BSM check box. This check box is selected by default.
   4. If you want to prohibit the exchange of unicast bootstrap packets on the multicast interface, clear the Unicast BSM check box. This check box is selected by default.
   5. In the DR priority field, enter the priority of the multicast interface. The highest-priority multicast interface becomes the designated router of the LAN segment. The greater the value, the higher the priority of the multicast interface. Range of values: 1 to 4,294,967,295. Default value: 1.
   6. In the Hello (sec.) field, enter the time interval in seconds that the multicast interface uses to send control packets to PIM neighbors. Range of values: 1 to 180. Default value: 30.
   7. In the Hold (sec.) field, enter the time interval in seconds that the multicast interface uses to receive control packets from PIM neighbors. If no control packets are received from a PIM neighbor within the specified time, the PIM interface considers this PIM neighbor unavailable. Range of values: 1 to 630. Default value: 105.
   8. If multiple IP addresses are assigned to a multicast interface and you want to use the specified IPv4 source address when sending PIM messages, enter the IPv4 address in the Source IP field.
5. Configure the IGMP protocol on the multicast interface:
   1. In the IGMP drop-down list, select Enabled. The default value is Disabled.
   2. In the Version drop-down list, select the version of the IGMP protocol on the multicast interface:
      • 2
      • 3. This is the default setting.
   3. In the Query interval (sec.) field, enter the time interval in seconds for sending queries from the multicast interface to clients. Queries are used to determine if multicast traffic needs to be sent to clients. Range of values: 1 to 250. Default value: 125.
   4. In the Query response time (sec.) field, enter the time in seconds that the multicast interface must wait to receive responses from clients. If no response to a query is received from the client within the specified time, the multicast interface does not send traffic packets. Range of values: 1 to 125. Default value: 10.
   5. If you want to specify multicast groups:
      1. Under Join group, click + Add and enter the IPv4 address of the multicast group.
      2. If you want to connect the multicast interface to the specified source of the multicast group, under Source address, enter the IPv4 address of the source.

      The multicast group is specified and displayed in the Join group and Source address sections. You can specify multiple multicast groups or delete multicast groups. To delete a multicast group, click the delete icon next to it.

      You need to specify multicast groups in one of the following cases:

      • The network segment has permanent clients to which you need to send traffic packets from a multicast group in a quick and stable way.
      • The network segment does not contain clients or hosts in the segment cannot send report messages, but traffic packets from a multicast group must be sent to this segment.
6. Click Create.

   The multicast interface is created and displayed in the table.

7. In the upper part of the settings area, click Save to save the settings of the CPE template or CPE device.

Editing a multicast interface

You can edit multicast interface settings in a CPE template or on a CPE device. A multicast interface edited in the CPE template is automatically modified on all CPE devices that use this CPE template.

To edit a multicast interface:

1. Edit a multicast interface in one of the following ways:
   • If you want to edit a multicast interface in a CPE template, go to the SD-WAN → CPE templates menu section, click the CPE template, and select the Multicast → Interfaces tab.
   • If you want to edit a multicast interface on a CPE device, go to the SD-WAN → CPE menu section, click the CPE device, select the Multicast → Interfaces tab, and select the Override check box.

   A table of multicast interfaces is displayed.

2. Click Edit next to the multicast interface that you want to edit.
3. This opens a window; in that window, if necessary, edit the multicast interface settings. For a description of the settings, see the instructions for creating a multicast interface.
4. Click Save.

   The multicast interface is modified and updated in the table.

5. In the upper part of the settings area, click Save to save the settings of the CPE template or CPE device.

Deleting a multicast interface

You can delete a multicast interface in a CPE template or on a CPE device. A multicast inerface deleted in the CPE template is automatically deleted on all CPE devices that use this CPE template.

Deleted multicast interfaces cannot be restored.

To delete a multicast interface:

1. Delete a multicast interface in one of the following ways:
   • If you want to delete a multicast interface in a CPE template, go to the SD-WAN → CPE templates menu section, click the CPE template, and select the Multicast → Interfaces tab.
   • If you want to delete a multicast interface on a CPE device, go to the SD-WAN → CPE menu section, click the CPE device, select the Multicast → Interfaces tab, and select the Override check box.

   A table of multicast interfaces is displayed.

2. Click Delete next to the multicast interface that you want to delete.
3. In the confirmation window, click Delete.

   The multicast interface is deleted and is no longer displayed in the table.

4. In the upper part of the settings area, click Save to save the settings of the CPE template or CPE device.