Implementing Layer-3 Multicast Routing
Multicast routing allows a host to send packets to a subset of all hosts as a group transmission rather than to a single host, as in unicast transmission, or to all hosts, as in broadcast transmission. The subset of hosts is known as group members and are identified by a single multicast group address that falls under the IP Class D address range from 126.96.36.199 through 188.8.131.52.
The multicast environment consists of senders and receivers. Any host, regardless of whether it is a member of a group, can send to a group. However, only the members of a group receive the message.
IGMP—IGMP is used between hosts on a LAN and the routers on that LAN to track the multicast groups of which hosts are members.
PIM SM—Protocol Independent Multicast in sparse mode (PIM-SM) is used between routers to track which multicast packets to forward to each other and to their directly connected LANs.
PIM SSM— Protocol Independent Multicast in Source-Specific Multicast (PIM-SSM) has the ability to report interest in receiving packets from specific source addresses (or from all but the specific source addresses), to an IP multicast address.
Auto RP— Automates the distribution of RP information in a multicast network
Static RP— Ability to statically configure an RP for a multicast group range.
PIM BSR—PIM boots trap router (BSR) provides a fault-tolerant, automated RP discovery and distribution mechanism that simplifies the Auto-RP process.
Prerequisites for Implementing Multicast Routing on NCS 5000 Series Router
- You must install and activate the multicast RPM package.
You must be familiar with IPv4 multicast routing configuration tasks and concepts.
Unicast routing must be operational.
Enables multicast routing and forwarding on all new and existing interfaces.
Router#config Router(config)#multicast-routing Router(config-mcast)#address-family ipv4 Router(config-mcast-default-ipv4)#interface all enable */In the above command, you can also indicate a specific interface (For example, interface TenGigE0/0/0/3) for enabling multicast only on that interface/* Router(config-mcast-default-ipv4)#commit
Router#show running multicast routing multicast-routing address-family ipv4 interface all enable !
Verify that the Interfaces are enabled for multicast.
Router#show mfib interface Interface : FINT0/RP0/CPU0 (Enabled) SW Mcast pkts in : 0, SW Mcast pkts out : 0 TTL Threshold : 0 Ref Count : 2 Interface : TenGigE0/0/0/1 (Enabled) SW Mcast pkts in : 0, SW Mcast pkts out : 0 TTL Threshold : 0 Ref Count : 7 Interface : TenGigE0/0/0/3 (Enabled) SW Mcast pkts in : 0, SW Mcast pkts out : 2 TTL Threshold : 0 Ref Count : 8