Pata Mpt Mpt group created on demand for mVPN SG pairs usually highbandwidth traffic

• 200Î, Ctaco Systems, Inc. All rights reaefved MPLS v20-«-«

VPN-aware multicast technology has introduced a new set of terminology.

Multicast VPNs introduce multicast routing information to the VRF table. When a PE router receives multicast data or control packets from a CE router, forwarding is performed according to information in the multicast virtual routing and forwarding instance (MVRF).

A set of MVRFs that can send multicast traffic to each other constitutes a multicast domain. For example, the multicast domain for a customer that wanted to send certain types of multicast traffic to all global employees would consist of all CE routers associated with that enterprise.

Cisco Mpls Mvpn Default Mdt Data Mdt

Multicast VPNs establish a static default MDT for each multicast domain. The default MDT defines the path used by PE routers to send multicast data and control messages to every other PE router in the multicast domain.

In the example here, a service provider has a multicast customer with offices in San Francisco, Los Angeles, New York, and Dallas. A one-way multicast presentation is occurring in Los Angeles. The service provider network supports all three sites associated with this customer, in addition to the site of a different enterprise customer.

The default MDT for the enterprise customer consists of provider routers and their associated PE routers. The other PE router is not part of the default MDT, because it is associated with a different customer.

Rifle Parts Diagrams Powerpoint

Multicast VPNs also support the dynamic creation of MDTs for high-bandwidth transmission. Data MDTs are a feature unique to Cisco IOS software. Data MDTs are intended for high-bandwidth sources such as full-motion video inside the VPN to ensure optimal traffic forwarding in the MPLS VPN core. The threshold at which the data MDT is created can be configured on a per-router or a per-VRF basis.

When the multicast transmission exceeds the defined threshold, the sending PE router creates the data MDT and sends a User Datagram Protocol (UDP) message that contains information about the data MDT to all routers in the default MDT. The statistics to determine whether a multicast stream has exceeded the data MDT threshold are examined once every 10 seconds. If multicast distributed switching is configured, the time period can be up to twice as long.

Data MDTs are created only for (S, G) multicast route entries within the VRF multicast routing table. They are not created for (*, G) entries regardless of the value of the individual source data rate.

In the example here, an employee joins the multicast session. The PE router associated with the employee site sends a join request that flows across the default MDT for the multicast domain of the customer. The PE router associated with the multicast session source receives the request.

The source CE router begins to send the multicast data to the associated PE router, which sends the multicast data along the default MDT. Immediately after sending the multicast data, the source PE router recognizes that the multicast data exceeds the bandwidth threshold at which a data MDT should be created. Therefore, the PE router creates a data MDT, sends a message to all routers using the default MDT that contains information about the data MDT, and, 3 seconds later, begins sending the multicast data for that particular stream using the data MDT. Only the PEs routers that have interested receivers for this source will join the data MDT and receive traffic on it.

PE routers maintain a Protocol Independent Multicast (PIM) relationship with other PE routers over the default MDT, and a PIM relationship with their directly attached PE routers.

The figure depicts the final flow of multicast data sourced from the multicast sender in Los Angeles to the multicast clients in New York and Dallas. Multicast data sent from the multicast sender is delivered in its original format to its associated PE router using sparse mode, bidir, or Source Specific Multicast (SSM). This PE router then encapsulates the multicast data and sends it across the data MDT using the configured MDT data groups. The mode used to deliver the multicast data across the data MDT is determined by the service provider and has no direct correlation with the mode used by the customer. The PE router in New York receives the data along the data MDT. That PE router de-encapsulates the packet and forwards it in its original format toward the multicast client using the mode configured by the customer.

Multicast VPNs Today (Cont.) Solution Concept

• P and PE routers multicast-enabled.

• Global multicast routing tables in the provider network.

• Globally, PEs configured to run PIM (global instance) with adjacent P routers.

• Multicast-enabled VPNs have a VPN multicast routing table (MVRF).

• No requirement to run same multicast protocols in the customer and provider network.

• If PIM is configured, PEs maintain PIM adjacencies with CE devices:

- No PIM adjacency between CEs devices non directly connected

• Normal PIM configuration in customer network:

«2043, Ctaco System«, Inc. All right« reserved. MPLS v20—-»

• P and PE routers multicast-enabled.

• Global multicast routing tables in the provider network.

• Globally, PEs configured to run PIM (global instance) with adjacent P routers.

• Multicast-enabled VPNs have a VPN multicast routing table (MVRF).

• No requirement to run same multicast protocols in the customer and provider network.

• If PIM is configured, PEs maintain PIM adjacencies with CE devices:

- No PIM adjacency between CEs devices non directly connected

• Normal PIM configuration in customer network:

«2043, Ctaco System«, Inc. All right« reserved. MPLS v20—-»

For every multicast domain of which an MVRF is a part, the PE router creates a multicast tunnel interface. A multicast tunnel interface is an interface that the MVRF uses to access the multicast domain. It can be thought of as a conduit that connects an MVRF and the global MVRF. One tunnel interface is created per MVRF.

To support VPN-aware multicast systems, PIM multicast (PIM, SSM, and so on) capability must be enabled on all affected P and PE routers. This addition results in a global multicast routing table being created in the provider network routers. The PE routes that have been configured to run PIM (global instance) will establish a PIM adjacency with neighboring P routers.

Multicast-enabled VPNs will create a VPN multicast routing table (MVRF).

There is no requirement to run the same multicast protocols in the customer and provider network. If PIM is configured as the CE-to-PE multicast protocol, the PE devices maintain PIM adjacencies with CE devices. No PIM adjacency will be established between CE devices that are not directly connected.

Normal PIM configuration (for example, rendezvous point [RP], RR, confederations) is accomplished in the customer network.

Multicast VPNs Today (Cont.) Configuration Example

Configuring VPN-aware multicast capability is a combination of standard VPN, standard multicast, and new VPN-aware multicast commands.

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