What is sparse dense mode?

What is sparse dense mode?

Sparse-dense mode, as the name implies, allows the interface to operate on a per-group basis in either sparse or dense mode. A group specified as dense is not mapped to an RP. Instead, data packets destined for that group are forwarded by means of PIM dense-mode rules.

What is dense mode multicast?

Dense mode: we forward multicast traffic on all interfaces until a downstream router requests us to stop fowarding. Sparse mode: we don’t forward multicast traffic on any interface until a downstream router requests us to forward it.

What is ip PIM sparse dense mode in Cisco?

Multicast PIM has three modes: PIM sparse mode: this is a “pull” model where we only forward multicast traffic when requested. PIM dense mode: this is a “push” model where we flood multicast traffic everywhere and then prune it when it’s not needed.

What is the purpose of an RP in PIM?

When the RP receives the PIM join, it will start forwarding the multicast traffic. This concept of joining the RP is called the RPT (Root Path Tree) or shared distribution tree. The RP is the root of our tree which decides where to forward multicast traffic to.

How does PIM SSM work?

PIM source-specific multicast (SSM) uses a subset of PIM sparse mode and IGMP version 3 (IGMPv3) to allow a client to receive multicast traffic directly from the source. PIM SSM uses the PIM sparse-mode functionality to create an SPT between the receiver and the source, but builds the SPT without the help of an RP.

What is the difference between dense mode and sparse mode?

One of the primary difference between Dense and Sparse mode is the multicast technique used. In Dense mode packets are flooded to the entire network and then branches where there are no receivers are eliminated. In Sparse mode packets branches distribution growth as new nodes join the multicast group.

What is the difference between sparse and dense mode?

Sparse mode assumes relatively fewer receivers. Dense mode is ideal for groups where many of the nodes will subscribe to receive the multicast packets, so that most of the routers must receive and forward these packets (groups of a high density). Dense Mode uses a fairly simple approach to handle IP multicast routing.

What is the difference between IGMP and PIM?

Important is the Note: To use PIM snooping, you must enable IGMP snooping on the switch. IGMP snooping restricts multicast traffic that exits through the LAN ports to which hosts are connected. IGMP snooping does not restrict traffic that exits through the LAN ports to which one or more multicast routers are connected.

What is Bidirectional PIM?

Bidirectional PIM builds bidirectional shared trees that are rooted at a rendezvous point (RP) address. Bidirectional traffic does not switch to shortest path trees (SPTs) as in PIM-SM and is therefore optimized for routing state size instead of path length.

What would be a reason to use sparse mode over dense mode multicast?

Sparse mode assumes relatively fewer receivers. Dense mode is ideal for groups where many of the nodes will subscribe to receive the multicast packets, so that most of the routers must receive and forward these packets (groups of a high density).

What is IP pim sparse mode?

A Protocol Independent Multicast (PIM) sparse-mode domain uses reverse-path forwarding (RPF) to create a path from a data source to the receiver requesting the data. When a receiver issues an explicit join request, an RPF check is triggered. 0.13) by means of each router’s RPF interface until it reaches the RP.

What is PIM in Juniper?

PIM is used for efficient routing to multicast groups that might span wide-area and interdomain internetworks. It is called “protocol independent” because it does not depend on a particular unicast routing protocol. Junos OS supports bidirectional mode, sparse mode, dense mode, and sparse-dense mode.

How does PIM Sparse-Dense Mode work in multicast?

PIM sparse-dense mode also allows us to flood the auto RP 224.0.1.39 and 224.0.1.40 multicast groups but in addition, it also floods all multicast traffic that we don’t have an RP for. In this lesson, I’ll show you how PIM sparse-dense mode forwards some traffic with sparse mode and other traffic with dense mode.

What is multicast 224.0.1.40 dense mode?

The multicast 224.0.1.40 address is used to share group-to-RP mapping information and as you can see above, this is flooded using dense mode. Above we see that R2 has received traffic to 224.0.1.40 using dense mode.

How are R1 and R2 neighbors in multicast mode?

As soon as we do this, R1 and R2 will become neighbors since they receive each others PIM hello packets.If they keep receiving them before the holddown timer is expired then they will keep seeing each other as PIM neighbors.: Let’s enable all the other interfaces. You need to enable PIM on all interfaces that will send or receive multicast traffic.

Which is the opposite of Pim dense mode?

In this lesson we’ll take a look at PIM sparse mode which works about opposite of how PIM dense mode works. With PIM dense mode, we flood multicast traffic everywhere and then we prune it. With PIM sparse mode we don’t forward any multicast traffic unless someone requests it.