Ingress multicast path management policies

Overview

Ingress multicast path management policies are used to manage ingress multicast path bandwidth settings, path decisions, and destination server details that collect and analyze IGMP events associated with residential subscribers. You can create the following ingress multicast path management policy types:

Ingress multicast bandwidth policy

Ingress multicast bandwidth policies are used to manage the ingress multicast path bandwidth of the multicast forwarding paths into the switching fabric. When Multicast Path Management is disabled (the default), two paths are available:

• a high-priority path, on which packets from queues classified as “expedited” are forwarded

• a low-priority path on which packets from queues classified as “non-expedited” are forwarded

When Multicast Path Management is enabled, an ingress multicast bandwidth policy can be used to manage the flow of multicast traffic through an MDA (IOM, IOM 2, or XMA) or the forwarding plane of an 2 x XP MDA IOM 3, IMM, or XCM.

The maximum number of bandwidth policies per NE is 32, including the default policy.

MDAs can be configured to use previously defined ingress multicast bandwidth policies. However, any path limits specified in the selected policy can be overridden for each MDA, if required.

Ingress multicast info policy

Ingress multicast info policies are used to define how each multicast channel is handled by NEs. The policy is assigned to a VPLS/VPRN service site or default routing instance, but the policy is actually used by the Ingress Multicast Bandwidth Manager, the ECMP Path Manager, and the Egress Multicast CAC Manager to determine the path through the switch fabric and to make decisions on joins to multicast streams.

The maximum number of ingress multicast info policies per NE is limited to 32, including the default policy.

MDAs can be configured to use previously-defined ingress multicast bandwidth policies. However, any path limits specified in the selected policy can be overridden for each MDA, if required.

Ingress multicast forwarding on L2-snooped and L3-routed IP multicast traffic can be explicitly configured by applying an ingress multicast info policy to a VPLS site (all types of VPLS are supported), a VPRN site, or the default routing instance.

An ingress multicast info policy consists of one or multiple named Bundles, which in turn, contain Channel ranges with possible overrides for individual channels.

• Bundles

  A Bundle groups a set of explicit multicast channels (or channel ranges) into a common bandwidth context for CAC functions (such as join decisions) using common preferences. The channels in the bundle are managed as a defined percentage of the available bandwidth.

  Bundles also simplify provisioning, since the default characteristics of the bundle channels are specified on the bundle level. These characteristics can be overridden at the Channel range level, or explicitly per channel.

  Each ingress multicast info policy has a default bundle named “default”. It cannot be edited or removed. Any multicast channel that fails to match a channel range within an explicit operator-defined bundle is associated with this default bundle.

  Note:

  The maximum number of Bundles per Info policies is limited to 32. This limit includes the default bundle, leaving 31 operator-defined bundles per Info policy.

• Channels and channel ranges

  Channel ranges are used to define a set of multicast channels contained in a bundle and to override the default channel settings in the containing bundle.

  A channel range is defined by a start destination multicast IP address and an end destination multicast IP address (both IP v4 and IPv6 are supported, but the start and end addresses must be of the same type). A channel in this context is a channel range where the start address and end address are identical.

  Note:

  After you create a channel range, it is not possible to modify the start address or end address.

  A channel range can contain multiple channel overrides. A channel override is used to specify an explicit setting for a channel within the range. The channel override is identified by a destination multicast IP address which falls between the start and end IP addresses of the channel range.

  Note:

  The 7450 ESS does not support channel ranges and channel overrides having IPv6 addresses. Therefore, the NFM-P does not allow the creation of such channel ranges and channel overrides on local ingress multicast info policies. In addition, the NFM-P removes any such channel ranges and channel overrides when synchronizing local ingress multicast info policies with their respective global policies.

• Dual stream selection

  Dual stream selection support allows a single multicast stream to be duplicated into two different transmission paths. The two paths may have different transmission characteristics, such as latency and jitter. Rather than select one stream for retransmission to the client, the duplicate stream protection feature evaluates each stream packet-by-packet, selecting the packet that first arrives (and is valid) for retransmission.

• Video quality monitoring

  VQM to provides the functionality to analyze the quality of a video stream just prior to reaching the STB of client in a IPTV network. Statistics reports and alarms can be generated for VQM, providing operators with a view of multicast video quality at the last mile of distribution.

Ingress multicast reporting policy

Ingress multicast reporting destination policies are used to specify the destination server for the collection of multicast reports. The policies are applied to residential subscriber IGMP policies.