Configuration — Ipv4 Multicast Routing NN47263-504 03.01 7 September 2009

Total Page:16

File Type:pdf, Size:1020Kb

Configuration — Ipv4 Multicast Routing NN47263-504 03.01 7 September 2009 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing Release: 10.2 Document Revision: 03.01 www.nortel.com .NN47263-504 Nortel Secure Router 2330/4134 Release: 10.2 Publication: NN47263-504 Document release date: 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. While the information in this document is believed to be accurate and reliable, except as otherwise expressly agreed to in writing NORTEL PROVIDES THIS DOCUMENT "AS IS" WITHOUT WARRANTY OR CONDITION OF ANY KIND, EITHER EXPRESS OR IMPLIED. The information and/or products described in this document are subject to change without notice. Nortel, Nortel Networks, the Nortel logo, and the Globemark are trademarks of Nortel Networks. THE SOFTWARE DESCRIBED IN THIS DOCUMENT IS FURNISHED UNDER A LICENSE AGREEMENT AND MAY BE USED ONLY IN ACCORDANCE WITH THE TERMS OF THAT LICENSE. Cisco is a trademark of Cisco Systems Inc. All other trademarks are the property of their respective owners. 3 . Contents New in this release 9 Features 9 Protocol Independent Multicast - Sparse Mode (PIM-SM) enhancements 9 Static multicast route 10 Multicast lookup in MRIB only 10 Multicast routing over VLANs 10 Distance Vector Multicast Routing Protocol (DVMRP) enhancements 10 Internet Group Management Protocol (IGMP) enhancements 11 IGMP snooping procedures 11 Multicast routing fundamentals 13 Overview of IP Multicast 13 Multicast host groups 15 Multicast addresses 16 Multicast protocols 16 Internet Group Management Protocol 17 IGMP queries 17 IGMP host reports 17 Host leave messages 18 Fast leave feature 18 Fast leave mode 19 IGMP snoop 19 Nortel Secure Router 2330/4134 implementation of IGMP 19 IGMP proxy 20 IGMP versions 20 Static multicast routing support 20 Distance Vector Multicast Routing Protocol 21 Reverse path forwarding 21 Pruning and grafting 22 DVMRP concepts and terminology 22 Nortel Secure Router 2330/4134 implementation of DVMRP 24 Protocol Independent Multicast-Sparse Mode 25 PIM-SM concepts and terminology 25 Shared trees and shortest-path trees 29 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing NN47263-504 03.01 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. 4 Receiver joining group 31 Receiver leaving group 32 Source sending packets to group 32 Required elements for PIM-SM operation 33 PIM-SM simplified example 33 PIM-SM Multipath 35 Anycast RP for PIM-SM 35 PIM-SSM 35 SSM features 36 PIM-SSM architecture 37 Nortel Secure Router 2330/4134 implementation of SSM and IGMP 38 Configuration limitations 39 PIM passive interfaces 39 Multicast routing over VLAN 40 Multicast routing procedures 41 Enabling multicast routing 41 Configuring multicast time-to-live 41 Example of configuring multicast time-to-live 42 Deleting multicast routing table entries 42 Example of deleting multicast routing table entries 43 Configuring a multicast static route 43 Clearing multicast forwarding entries 44 Configuring multicast lookup in MRIB only 45 Displaying multicast interface information 46 Displaying the IP multicast routing table 46 Example of displaying the IP multicast routing table 46 DVMRP procedures 47 Enabling DVMRP 47 Assigning a metric value 47 Example of assigning a metric value 48 Configuring route report burst interval 48 Example of configuring route report burst interval 49 Rejecting non-pruners 49 Configuring the global MFC timeout 50 Configuring neighbor change logging 50 Configuring the global triggered updates interval 51 Configuring the status of the DVMRP holddown timer 51 Configuring the DVMRP route expiration timeout 52 Configuring the global DVMRP unconfirmed route timeout 53 Configuring the global DVMRP neighbor timeout 54 Configuring the global DVMRP neighbor probe interval 55 Configuring the global DVMRP switch timeout 56 Configuring DVMRP default route advertisement on an interface 56 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing NN47263-504 03.01 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. 5 Configuring DVMRP default route listening on an interface 57 Configuring the DVMRP prune lifetime for an interface 58 Displaying DVMRP statistics 58 Showing interface information 59 Example of showing interface information 59 Showing neighbor information 60 Example of showing neighbor information 60 Showing prune information 60 Showing route information 61 Example of showing route information 62 Showing statistics information 62 Deleting DVMRP prune states 62 Examples of deleting DVMRP prune states 63 Deleting DVMRP unicast routes 63 Example of deleting DVMRP unicast routes 63 PIM-SM procedures 65 Registering an accept filter 65 Example of registering an accept filter 65 Configuring candidate bootstrap router 66 Example of configuring candidate bootstrap router 66 Calculate register checksum 67 Setting the source address for PIM register 67 Example of setting the source address for PIM register 68 Configuring source-specific multicast 68 Example of configuring source-specific multicast 69 Configuring to ignore RP set priority value 69 Configuring the PIM RP address 69 Example of configuring the PIM RP address 70 Configuring the PIMv2 RP candidate 70 Example of configuring the PIMv2 RP candidate 71 Configuring a group to have no source-tree switching threshold 71 Example of configuring source-tree switching threshold 72 Configuring PIM router DR priority 72 Example of configuring PIM router DR priority 72 Configuring PIM to exclude Gen-id option 73 Configuring a PIM peer filter 73 Example of configuring a PIM peer filter 74 Enabling a BSR border router 74 Setting Hello message interval 74 Example of setting Hello message interval 75 Enabling PIM sparse-mode operation 75 Configuring PIM neighbor change logging 76 Configuring an Anycast member RP address 77 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing NN47263-504 03.01 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. 6 Configuring PIM multipath 77 Displaying PIM RPF 78 Clearing PIM statistics 79 Displaying bootstrap router information 79 Displaying the PIM Tree Information Base 80 Example of displaying the PIM Tree Information Base 80 Displaying PIM interface information 80 Example of displaying PIM interface information 81 Displaying PIM neighbor information 81 Example of displaying PIM neighbor information 81 Displaying PIM Rendezvous Point information 82 Example of displaying PIM Rendezvous Point information 82 Clearing PIM bootstrap router information 82 IGMP interface configuration procedures 83 Configuring an IGMP access group 83 Example of configuring an IGMP access group 84 Configuring leave behavior 84 Example of configuring leave behavior 85 Configuring query interval 85 Example of configuring query interval 86 Configuring robustness variable 86 Example of configuring robustness variable 86 Configuring query maximum response time 87 Example of configuring query maximum response time 87 Configuring querier timeout 88 Example of configuring querier timeout 88 Configuring the IGMP last member query count 89 Example of configuring the IGMP last member query counter 89 Configuring the IGMP last member query interval 90 Example of configuring the IGMP last member query interval 90 Enabling IGMP snooping 90 Setting the IGMP version 91 Example of setting the IGMP version 91 Configuring global IGMP state limit 92 Configuring IGMP group limit on an interface 92 Configuring the SSM mapping status 93 Configuring a static SSM map 94 Configuring a static IGMP group on an interface 95 Displaying IGMP statistics 96 Clearing IGMP statistics 96 Displaying IGMP group membership information 97 Example of displaying IGMP group membership information 97 Displaying IGMP interface information 98 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing NN47263-504 03.01 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. 7 Example of displaying IGMP interface information 98 Displaying IGMP snooping information 98 Clearing IGMP group cache entries 99 Example of clearing IGMP group cache entries 99 Clearing IGMP interface entries 99 Example of clearing IGMP interface entries 100 IGMP snooping procedures 101 Configuring IGMP snooping status on a VLAN 101 Configuring mrouter ports for IGMP snooping 102 Configuring IGMP-snooping querier on a VLAN 103 Configuring IGMP report suppression 103 Displaying IGMP mrouter configuration 104 Clearing the IGMP snooping mrouter configuration 105 Clearing IGMP snooping statistics 105 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing NN47263-504 03.01 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. 8 Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing NN47263-504 03.01 7 September 2009 Copyright © 2007-2009 Nortel Networks. All Rights Reserved. 9 . New in this release The following section details what is new in Nortel Secure Router 2330/4134 Configuration — IPv4 Multicast Routing, (NN47263-504) for release 10.2. ATTENTION In this document, the term Secure Router 2330/4134 is used interchangeably to refer to the Secure Router 2330 and the Secure Router 4134. Features See the following sections for information about supported features: • “Protocol Independent Multicast - Sparse Mode (PIM-SM) enhancements” (page 9) • “Static multicast route” (page 10) • “Multicast lookup in MRIB only” (page 10) • “Multicast routing over VLANs” (page 10) • “Distance Vector Multicast Routing Protocol (DVMRP) enhancements” (page 10) •
Recommended publications
  • 15-744: Computer Networking Multicast Routing Example Applications Overview
    Multicast Routing • Unicast: one source to one destination • Multicast: one source to many destinations 15-744: Computer Networking • Two main functions: • Efficient data distribution • Logical naming of a group L-20 Multicast 2 Example Applications Overview • Broadcast audio/video • IP Multicast Service Basics • Push-based systems • Software distribution • Multicast Routing Basics • Web-cache updates • Teleconferencing (audio, video, shared • Overlay Multicast whiteboard, text editor) • Multi-player games • Reliability • Server/service location • Other distributed applications • Congestion Control 3 4 1 IP Multicast Architecture Multicast – Efficient Data Distribution Src Src Service model Hosts Host-to-router protocol (IGMP) Routers Multicast routing protocols (various) 5 6 Multicast Router Responsibilities IP Multicast Service Model (rfc1112) • Learn of the existence of multicast groups • Each group identified by a single IP address (through advertisement) • Groups may be of any size • Identify links with group members • Members of groups may be located anywhere in the Internet • Establish state to route packets • Members of groups can join and leave at will • Replicate packets on appropriate interfaces • Senders need not be members • Routing entry: • Group membership not known explicitly • Analogy: Src, incoming interface List of outgoing interfaces • Each multicast address is like a radio frequency, on which anyone can transmit, and to which anyone can tune-in. 7 8 2 IP Multicast Addresses Multicast Scope Control – Small TTLs • Class
    [Show full text]
  • IP Multicast Routing Technology Overview
    IP Multicast Routing Technology Overview • Information About IP Multicast Technology, on page 1 • Additional References for IP Multicast, on page 15 Information About IP Multicast Technology This section provides information about IP multicast technology. About IP Multicast Controlling the transmission rate to a multicast group is not supported. At one end of the IP communication spectrum is IP unicast, where a source IP host sends packets to a specific destination IP host. In IP unicast, the destination address in the IP packet is the address of a single, unique host in the IP network. These IP packets are forwarded across the network from the source to the destination host by devices. At each point on the path between source and destination, a device uses a unicast routing table to make unicast forwarding decisions, based on the IP destination address in the packet. At the other end of the IP communication spectrum is an IP broadcast, where a source host sends packets to all hosts on a network segment. The destination address of an IP broadcast packet has the host portion of the destination IP address set to all ones and the network portion set to the address of the subnet. IP hosts, including devices, understand that packets, which contain an IP broadcast address as the destination address, are addressed to all IP hosts on the subnet. Unless specifically configured otherwise, devices do not forward IP broadcast packets, so IP broadcast communication is normally limited to a local subnet. IP multicasting falls between IP unicast and IP broadcast communication. IP multicast communication enables a host to send IP packets to a group of hosts anywhere within the IP network.
    [Show full text]
  • WAN-LAN PIM Multicast Routing and LAN IGMP FEATURE OVERVIEW and CONFIGURATION GUIDE
    Technical Guide WAN-LAN PIM Multicast Routing and LAN IGMP FEATURE OVERVIEW AND CONFIGURATION GUIDE Introduction This guide describes WAN-LAN PIM Multicast Routing and IGMP on the LAN and how to configure WAN-LAN PIM multicast routing and LAN IGMP snooping. The AlliedTelesis Next Generation Firewalls (NGFWs) can perform routing of IPv4 and IPv6 multicast, using PIM-SM and PIM-DM. Also, switching interfaces of the NGFWs are IGMP aware, and will only forward multicast steams to these switch ports that have received reports. IGMP snooping allows a device to only forward multicast streams to the links on which they have been requested. PIM Sparse mode requires specific designated routers to receive notification of all streams destined to specific ranges of multicast addresses. When a router needs to get hold of a given group, it sends a request to the designated Rendezvous Point for that group. If there is a source in the network that is transmitting a stream to this group, then the Rendezvous Point will be receiving it, and will forward it to the requesting router. C613-22042-00 REV A alliedtelesis.com x Products and software version that apply to this guide Contents Introduction.............................................................................................................................................................................1 Products and software version that apply to this guide .......................................................................2 Configuring WAN-LAN PIM Multicast Routing and LAN IGMP Snooping........................................3
    [Show full text]
  • Routing Review Autonomous System Concept
    Routing Review Autonomous System Concept • Term Autonomous System (AS) to specify groups of routers • One can think of an AS as a contiguous set of networks and routers all under control of one administrative authority – For example, an AS can correspond to an ISP, an entire corporation, or a university – Alternatively, a large organization with multiple sites may choose to define one AS for each site – In particular, each ISP is usually a single AS, but it is possible for a large ISP to divide itself into multiple ASs • The choice of AS size can be made for – economic, technical, or administrative reasons The Two Types of Internet Routing Protocols • All Internet routing protocols are divided into two major categories: – Interior Gateway Protocols (IGPs) – Exterior Gateway Protocols (EGPs) • After defining the two categories – we will examine a set of example routing protocols that illustrate each category • Interior Gateway Protocols (IGPs) • Exterior Gateway Protocols (EGPs) The Two Types of Internet Routing Protocols Interior Gateway Protocols (IGPs) • Routers within an AS use an IGP exchange routing information • Several IGPs are available – each AS is free to choose its own IGP • Usually, an IGP is easy to install and operate • IGP may limit the size or routing complexity of an AS The Two Types of Internet Routing Protocols Exterior Gateway Protocols (EGPs) • A router in one AS uses an EGP to exchange routing information with a router in another AS • EGPs are more complex to install and operate than IGPs – but EGPs offer more flexibility
    [Show full text]
  • Unicast Multicast IP Multicast Introduction
    Outline 11: ❒ IP Multicast ❒ Multicast routing IP Multicast ❍ Design choices ❍ Distance Vector Multicast Routing Protocol (DVMRP) Last Modified: ❍ Core Based Trees (CBT) ❍ Protocol Independent Multicast (PIM) 4/9/2003 1:15:00 PM ❍ Border Gateway Multicast Protocol (BGMP) ❒ Issues in IP Multicast Deplyment Based on slides by Gordon Chaffee Berkeley Multimedia Research Center URL: http://bmrc.berkeley.edu/people/chaffee 4: Network Layer 4a-1 4: Network Layer 4a-2 What is multicast? Unicast ❒ ❒ 1 to N communication Problem Sender ❍ ❒ Nandwidth-conserving technology that Sending same data to reduces traffic by simultaneously many receivers via unicast is inefficient delivering a single stream of information to R multiple recipients ❒ Example ❒ Examples of Multicast ❍ Popular WWW sites ❍ Network hardware efficiently supports become serious multicast transport bottlenecks • Example: Ethernet allows one packet to be received by many hosts ❍ Many different protocols and service models • Examples: IETF IP Multicast, ATM Multipoint 4: Network Layer 4a-3 4: Network Layer 4a-4 Multicast IP Multicast Introduction ❒ Efficient one to many Sender ❒ Efficient one to many data distribution data distribution ❍ Tree style data distribution ❍ Packets traverse network links only once R ❒ Location independent addressing ❍ IP address per multicast group ❒ Receiver oriented service model ❍ Applications can join and leave multicast groups ❍ Senders do not know who is listening ❍ Similar to television model ❍ Contrasts with telephone network, ATM 4: Network Layer
    [Show full text]
  • Broadcast and Multicast Routing
    Broadcast and Multicast Routing Daniel Zappala CS 460 Computer Networking Brigham Young University Broadcast Multicast Service Model DVMRP CBT PIM Status Group Communication • How can the Internet provide efficient group communication? • send the same copy of a data stream (e.g. TV show, teleconference) to a group of users • need to find where everyone is located (routing) • need to avoid sending a separate copy to everyone 2/34 Broadcast Multicast Service Model DVMRP CBT PIM Status Choices • unicast: send a separate copy of each packet to each host • broadcast: send one copy of each packet, the network will replicate it and deliver it to all hosts • broadcast provides efficient network flooding • multicast: send one copy of each packet, the network will replicate it and deliver it to only those hosts that want it • multicast provides efficient group communication 3/34 Broadcast Broadcast Multicast Service Model DVMRP CBT PIM Status Broadcast • send a copy of each packet to all your neighbors • need to eliminate duplicates • sequence numbers: drop a sequence number previously seen • reverse path forwarding: accept the packet only on the incoming interface used to send packets to the source 5/34 Broadcast Multicast Service Model DVMRP CBT PIM Status Spanning and Steiner Trees • spanning tree • connect all routers in the entire Internet • easy to build a minimum cost tree • Steiner Tree • connect only those routers with multicast members for a particular group • NP-complete (one of the original 21!) • many different heuristics, but often centralized
    [Show full text]
  • Introduction to IP Multicast Routing
    Introduction to IP Multicast Routing by Chuck Semeria and Tom Maufer Abstract The first part of this paper describes the benefits of multicasting, the Multicast Backbone (MBONE), Class D addressing, and the operation of the Internet Group Management Protocol (IGMP). The second section explores a number of different algorithms that may potentially be employed by multicast routing protocols: - Flooding - Spanning Trees - Reverse Path Broadcasting (RPB) - Truncated Reverse Path Broadcasting (TRPB) - Reverse Path Multicasting (RPM) - Core-Based Trees The third part contains the main body of the paper. It describes how the previous algorithms are implemented in multicast routing protocols available today. - Distance Vector Multicast Routing Protocol (DVMRP) - Multicast OSPF (MOSPF) - Protocol-Independent Multicast (PIM) Introduction There are three fundamental types of IPv4 addresses: unicast, broadcast, and multicast. A unicast address is designed to transmit a packet to a single destination. A broadcast address is used to send a datagram to an entire subnetwork. A multicast address is designed to enable the delivery of datagrams to a set of hosts that have been configured as members of a multicast group in various scattered subnetworks. Multicasting is not connection oriented. A multicast datagram is delivered to destination group members with the same “best-effort” reliability as a standard unicast IP datagram. This means that a multicast datagram is not guaranteed to reach all members of the group, or arrive in the same order relative to the transmission of other packets. The only difference between a multicast IP packet and a unicast IP packet is the presence of a “group address” in the Destination Address field of the IP header.
    [Show full text]
  • Advanced Network Training Multicast Larry Mathews Systems Engineer [email protected] Training Objectives
    Division of Brocade Advanced Network Training Multicast Larry Mathews Systems Engineer [email protected] Training Objectives ‒ Session will concentrate on Multicast with emphasis on Protocol Independent Multicast Protocol (PIM) ‒ Multicast in a ITS environment will be emphasized ‒ Attendees will have a good understanding on how multicast works ‒ Primary focus is on technology not vendor specifics 2 Agenda ‒ Multicast Overview • What is a multicast • Why use it • Multicast elements • Multicast IPv4 addressing ‒ Internet Group Management Protocol (IGMP) Overview • Where and why is IGMP used • IGMP packet structure • IGMPv2 vs. IGMPv3 • How does IGMP work ‒ Protocol Independent Multicast Protocol Overview • Layer 2 vs Layer 3 protocols • Where does PIM function • PIM-Dense Mode (DM) vs PIM-Sparse Mode (SM) • PIM-Source Specific Multicast (SSM) overview 3 Agenda Continued ‒ Protocol Independent Multicast (PIM) Protocol Operation • PIM components • Reverse Path Forwarding (RPF) – Multicast vs Unicast routing • PIM packet formats ‒ Demonstration of Router configuration and operation • Best practice • Configuration requirements • Demonstration of successful PIM operation ‒ Diagnostics and Troubleshooting • Multicast packet capture • Using command line to identify issues 4 Multicast Overview 5 What is a Multicast ‒ In computer networking, multicast is a one-to-many or many-to-many distribution ‒ M/C is group communication where information is addressed to a group of destination computers simultaneously. ‒ IP multicast is a technique for one-to-many
    [Show full text]
  • Chapter 4 Network Layer
    Chapter 4 Network Layer A note on the use of these ppt slides: We’re making these slides freely available to all (faculty, students, readers). Computer They’re in PowerPoint form so you see the animations; and can add, modify, and delete slides (including this one) and slide content to suit your needs. Networking: A Top They obviously represent a lot of work on our part. In return for use, we only ask the following: Down Approach v If you use these slides (e.g., in a class) that you mention their source th (after all, we’d like people to use our book!) 6 edition v If you post any slides on a www site, that you note that they are adapted Jim Kurose, Keith Ross from (or perhaps identical to) our slides, and note our copyright of this Addison-Wesley material. March 2012 Thanks and enjoy! JFK/KWR All material copyright 1996-2012 J.F Kurose and K.W. Ross, All Rights Reserved Network Layer 4-1 Chapter 4: outline 4.1 introduction 4.5 routing algorithms 4.2 virtual circuit and § link state datagram networks § distance vector 4.3 what’s inside a router § hierarchical routing 4.4 IP: Internet Protocol 4.6 routing in the Internet § datagram format § RIP § IPv4 addressing § OSPF § BGP § ICMP § IPv6 4.7 broadcast and multicast routing Network Layer 4-2 Interplay between routing, forwarding routing algorithm determines routing algorithm end-end-path through network forwarding table determines local forwarding table local forwarding at this router dest address output link address-range 1 3 address-range 2 2 address-range 3 2 address-range 4 1 IP destination
    [Show full text]
  • Junos Multicast Routing (JMR)
    Junos Multicast Routing (JMR) Junos Multicast Routing (JMR) Engineering Simplicity COURSE LEVEL COURSE OVERVIEW Junos Multicast Routing (JMR) is an advanced-level This two-day course is designed to provide students with detailed coverage of multicast course. protocols including Internet Group Management Protocol (IGMP), Protocol Independent Multicast-Dense Mode (PIM-DM), Protocol Independent Multicast-Sparse Mode (PIM- SM), Bidirectional PIM, and Multicast Source Discovery Protocol (MSDP). AUDIENCE Through demonstrations and hands-on labs, students will gain experience in configuring and monitoring the Junos OS and monitoring device and protocol This course benefits individuals responsible for implementing, monitoring, and troubleshooting operations. This course utilizes Juniper Networks vMX Series devices for the hands-on multicast components in a service provider’s component, but the lab environment does not preclude the course from being applicable to other Juniper hardware platforms running the Junos OS. The Juniper Networks vMX network. Series devices run Junos OS Release 16.2R1.6. PREREQUISITES Students should have basic networking knowledge OBJECTIVES and an understanding of the Open Systems • Describe IP multicast traffic flow. Interconnection (OSI) model and the TCP/IP • Identify the components of IP multicast. protocol suite. Students should also have working knowledge of security policies. • Explain how IP multicast addressing works. • Describe the need for reverse path forwarding (RPF) in multicast. Students should also attend the Introduction to the • Explain the role of IGMP and describe the available IGMP versions. Junos Operating System (IJOS) and Junos • Configure and monitor IGMP. Intermediate Routing (JIR) courses prior to • Identify common multicast routing protocols. attending this class. • Explain the differences between dense-mode and sparse-mode protocols.
    [Show full text]
  • Broadcast Routing Broadcasting: Sending a Packet to All N Receivers
    Broadcast Routing Broadcasting: sending a packet to all N receivers . routing updates in LS routing . service/request advertisement in application layer (e.g., Novell) Broadcast algorithm 1: N point-to-point sends . send packet to every destination, point-to-point . wasteful of bandwidth . requires knowledge of all destinations Broadcast algorithm 2: flooding . when node receives a broadcast packet, send it out on every link . node may receive many copies of broadcast packet, hence must be able to detect duplicates Broadcast Routing: Reverse Path Forwarding Goal: avoid flooding duplicates Assumptions: . A wants to broadcast . all nodes know predecessor node on shortest path back to A Reverse path forwarding: if node receives a broadcast packet . if packet arrived on predecessor on shortest path to A, then flood to all neighbors . otherwise ignore broadcast packet - either already arrived, or will arrive from predecessor 1 Reverse Path Forwarding . flood if packet arrives from source on link that router would use to send packets to source . otherwise discard . rule avoids flooding loops . uses shortest path tree from destinations to source (reverse tree) routing table to use S y x S to group w y z 2 Distributing routing information Q: is broadcast algorithm like reverse path forwarding good for distributing Link State updates (in LS routing)? A: First try (at LS broadcast distribution): . each router keeps a copy of most recent LS packet (LSP) received from every other node . upon receiving LSP(R) from router R: ◆ if LSP(R) not identical to stored copy then store LSP(R), update LS info for R, and flood LSP(R) else ignore duplicate How can this protocol fail? 2nd Try (at LS Broadcast Distribution) Each router puts a sequence number on its LSP's .
    [Show full text]
  • Vmware Virtual SAN Layer 2 and Layer 3 Network Topologies Deployments
    VMware Virtual SAN Layer 2 and Layer 3 Network Topologies Deployments Multicast Groups on the Layer 3 segment where the receiver is connected. This allows the switch to keep a table of the individual receivers that need a copy of the Multicast Group traffic. The participating hosts in a Virtual SAN cluster will negotiate for IGMP version 3. If the network does not support IGMP version 3, the hosts will fall back to IGMP version 2. VMware recommends that the same version of IGMP be used in all Layer 3 segments. Protocol-Independent Multicast (PIM) Protocol-Independent Multicast (PIM) is a family of Layer 3 multicast routing protocols that provide different communication techniques for IP Multicast traffic to reach receivers that are in different Layer 3 segments from the Multicast Groups sources. There are different versions of PIM, each of which is best suited for different IP Multicast topologies. The main four versions of PIM are these: • PIM Dense Mode (PIM-DM) – Dense Mode works by building a unidirectional shortest-path tree from each Multicast Groups source to the Multicast Groups receivers, by flooding multicast traffic over the entire Layer 3 Network and then pruning back branches of the tree where no receivers are present. Dense Mode is straightforward to implement and it is best suited for small Multicast deployments of one-to-many. • PIM Sparse Mode (PIM-SM) – Sparse Mode avoids the flooding issues of Dense Mode by assigning a root entity for the unidirectional Multicast Groups shortest-path tree called a rendezvous point (RP). The rendezvous point is selected in a per Multicast Group basis.
    [Show full text]