CCNP CCIE Complete

PIM DM pruning Grafting PIM DM is also ready to forward multicast data after a previously inactive interface becomes active. This is done through the process of grafting. When a host sends an IGMP group membership report to the router, ... [full story]

PIM DM flooding Host A Host F Host B Host C Host D Host E Source for 224.2.125.125 Member 224.2.125.125 Member 224.2.125.125 Member 224.2.125.125 Router 1 Router 2 Router 3 Host G Router 5 [full story]

PIM DM There are three types of Protocol Independent Multicast (PIM): sparse mode, dense mode, and a combination of the two. Although PIM dense mode (PIM DM) maintains several functions, the ones that are discussed here are flooding, pruning, and ... [full story]

Intra-Area and Inter-Area MOSPF When discussing the difference between intra-area and inter-area MOSPF, you must remember that all areas connect through Area 0, the backbone. In large networks, having full multicast tables in addition to all the unicast tables flow ... [full story]

Intra-Area MOSPF OSPF route information is shared via different link-state advertisement (LSA) types. LSAs are flooded throughout an area to give all OSPF-enabled routers a logical image of the network topology. When changes are made to the topology, new LSAs ... [full story]

CBT data distribution Host A Host F Host B Host C Host D Host E Source for 224.2.125.125 Member Member Member New member of 224.2.125.125 Router 1 Router 2 Router 3 Host G Router 5 Router 4 Forward multicast data ... [full story]

CBT data distribution Host A Host F Host B Host C Host D Host E Source for 224.2.125.125 Member Member Member New member of 224.2.125.125 Router 1 Router 2 Router 3 Host G Router 5 Router 4 Forward multicast data ... [full story]

Enabling IP Multicast Routing As we have said, multicast routing must be enabled on the router. This step is very straightforward, but without it, multicast will not work. Let’s look at a configuration of a router that does not have ... [full story]

Configuring IP Multicast Routing When configuring multicast, keep in mind that many options and protocols can be configured. This is why it is so important that you have previously prepared and planned for the actual configuration. It isn’t something that ... [full story]

End-to-End IP Multicast Part of deploying multicast is the determination of how much of the network should be multicast enabled. This is an important decision because it directly affects many aspects of multicast implementation. To strategically place the RPs, you ... [full story]

Planning and Preparing for Using IP Multicast You now know that multicast networks behave differently from unicast networks. It is important to keep this in mind when planning the deployment of an IP multicast network. You should take several factors ... [full story]

Source-Specific Multicasting (SSM) Within any multicast group, it is possible for two sources to exist. Therefore, as multiple listeners join the group, they all receive multicast streams from both sources. This can be filtered out, but possibly not until the ... [full story]

Multicast Source Discovery Protocol (MSDP) In PIM sparse mode, the routers closest to the sources and receivers register with the RP, so the RP knows about all the sources and receivers for any group. But it is possible that several ... [full story]

PIM SM pruning Router 5 receives an IGMP message requesting the removal of Host G from the group. Because Host G was the last active member of the group, the (∗, G) entry is set to null 0 and a ... [full story]

PIM SM PIM sparse mode (PIM SM) also uses the architecture of shared tree distribution. There is an RP router that acts as the root of the shared tree. Unlike CBT, however, PIM SM uses the unidirectional shared tree distribution ... [full story]

The Fast-Leave Trap Fast-Leave is a great tool in an organization that uses quite a bit of multicasting. There can be a problem though, when using it in a network where spanning tree changes frequently. When a switch configured for ... [full story]

IP multicast mapped to MAC multicast 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 0 1 1 1 1 0 0 1 1 1 0 x x x x x ... [full story]

Understanding and Configuring Multicast Operation THE CCNP EXAM TOPICS COVERED IN THIS CHAPTER INCLUDE THE FOLLOWING:
Describe the functionality of CGMP.
Describe how switches facilitate multicast traffic.
Translate multicast addresses into MAC addresses.
Enable CGMP on ... [full story]

Multicast Overview Just as blue, yellow, and red are different and each has its own place within the spectrum of visible light, unicast, broadcast, and multicast are different in that each is used to achieve a specific purpose or fulfill ... [full story]

Unicast Unicast is used for direct host-to-host communication. When the layer 3 protocol data unit (PDU, or packet) is formed, two layer 3 IP addresses are added to the IP header. These are the source and destination IP addresses. They ... [full story]

Unicast communication The unicast process occurs between two hosts only. A single destination address is used to ensure that data is sent to only one host. This could be client-to-server, server-to-client, or peerto- peer. It doesn’t matter, so long as ... [full story]

Broadcast Now that you have a good understanding of unicast, we can discuss the principle of broadcast communication on networks. Whereas unicast messages target a single host on a network (unicast communication can be compared to sending an e-mail to ... [full story]

Broadcast message on a network Server 172.16.1.0/24 Host C Host A Host B Host X Server 172.16.1.0/24 Host C Host X Host A Host B Multicast Overview 589 A good example of a broadcast message is an Address Resolution Protocol ... [full story]

Multicast Multicast is a different beast entirely. At first glance, it appears to be a hybrid of unicast and broadcast communication, but that isn’t quite accurate. Multicast does allow point-to-multipoint communication, which is similar to broadcasts, but it happens in ... [full story]

Multicast communication The key to multicast is the addressing structure. This is key because all communication is based on addressing. In unicast communication, there is a unique address for every host on a network. In broadcast communication, a global address ... [full story]

Using Multicast Addressing Just as with mailing lists, there are several different groups that users or applications can subscribe to. The range of multicast addresses starts with 224.0.0.0 and goes through 239.255.255.255. As you can see, this range of addresses ... [full story]

IP Multicast Reserved Addresses Address Purpose Reserved Category 224.0.0.0–224.0.0.18 Use by network protocols Local-link 224.0.0.1 All hosts Local-link 224.0.0.2 All routers Local-link 224.0.0.19–224.0.0.255 Unassigned Local-link 224.0.1.0–224.0.1.255 Multicast applications Misc. applications 224.0.1.1 NTP Misc. applications 224.0.1.8 NIS+ Misc. applications 224.0.1.39 Cisco-RP-Announce ... [full story]

Each address range is managed by the Internet Address Number Authority (IANA). Due to the limited number of multicast addresses, there are very strict requirements for new assignments within this address space. The 239.0.0.0–239.255.255.255 range is equivalent in purpose to ... [full story]

Mapping IP Multicast to Ethernet Multicast addressing began on MAC addresses. Growth needs required that there be a way to use multicast across routers instead of limiting it to the physical segment where hosts were located. In regular unicast, MAC ... [full story]

Frame Modification It is important to understand that this shortcut switching occurs at layer 3. The layer 2 frame addresses (that are a part of the conversation) coming after the first frame are rewritten by the switch. Normally, a router ... [full story]

Identifying Enable Packets Enable packets are the missing piece of the flow cache puzzle. Just as the MLS switch watches all incoming frames destined for the MLS router’s MAC addresses, it also watches all the packets coming from the MLS ... [full story]

Candidate packet The state of the MLS cache is only partial at this stage. A complete flow cache has not been established because the MLS-SE has only seen a packet come in and be forwarded to the router. It still ... [full story]