Licensing Requirements and Limitations for MSDP

Multicast source

A device that sends multicast data to receiver hosts. For example, a video server is a multicast source.

IPv4 Protocol Independent Multicast (PIM) device

A device that uses the IPv4 PIM protocol to generate and maintain multicast routing entries and forwards multicast data based on multicast routing entries. On an IPv4 multicast network, all Layer 3 devices must run IPv4 PIM; otherwise, multicast forwarding paths cannot be established.

Multicast Source Discovery Protocol (MSDP) device

A device that forwards multicast data from one PIM network to another. For example, if multicast data needs to be transmitted between two autonomous systems (ASs), the devices at the border of the ASs must run the MSDP protocol.

Multicast VPN device

Multicast VPN enables multicast data of a private network to be transmitted over a public network. Multicast VPN devices are used on VPN networks. For example, if two sites of a VPN network need to exchange multicast data across a public network, multicast VPN needs to be configured on the PE devices.

IGMP querier

A device that exchanges IGMP messages with receiver hosts to create and maintain group memberships. On a multicast network, Layer 3 devices connected to network segments of receivers must run the IGMP protocol or be configured with static IGMP groups. Otherwise, upstream PIM devices cannot know the multicast groups that users want to join, and therefore cannot establish multicast forwarding paths.

IGMP snooping device

A device that listens to IGMP messages exchanged between upstream Layer 3 multicast devices and receiver hosts to create and maintain Layer 2 multicast forwarding entries, which are used for accurate multicast data forwarding on a Layer 2 network. To prevent broadcasting of multicast packets on a Layer 2 network and conserve network bandwidth, it is recommended that you configure IGMP snooping on Layer 2 devices.

Receiver

A multicast user that receives multicast data. A receiver can be a PC, a set top box, or any device with multicast client installed.