HP Routing Services -UX 11i v2 manual Multicast Groups

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Overview

The mrouted Routing Daemon

Normally, IP multicast addresses are mapped to 802.3 or Ethernet multicast addresses. The IP multicasting addressing scheme, similar to Ethernet’s scheme, uses the datagram’s destination address to indicate multicast delivery.

When an IP multicast address is mapped to an Ethernet multicast address, the low-order 23 bits of the IP multicast address are placed into the low-order 23 bits of the special Ethernet multicast address. The hexadecimal value of the special Ethernet multicast address is

01-00-5E-00-00-00. The resultant Ethernet address, however, is not unique, because only 23 out of the 28 bits representing the multicast address are used.

Multicast Groups

A multicast group comprises hosts with an intention to join the multicast group by listening to the same IP multicast address. Group membership is dynamic, that is, a host may join or leave a group at any time. A host may be a member of one or more groups simultaneously. Additionally, a host is allowed to send multicast datagrams to a group without being a member of the group.

You can assign multicast addresses to transient groups because the multicast address are often temporary. A typical transient group scenario is when users run an application that dynamically registers to specific multicast addresses, which are discarded later when all members of the group have left. Some multicast addresses may be assigned to permanent groups that always exist, even when their membership is empty.

Both hosts and mrouted routers that participate in IP multicasting use the Internet Group Management Protocol (IGMP) to communicate multicast group information among themselves. Hosts use IGMP to inform mrouted routers that they are joining a group. mrouted routers use IGMP to pass multicast routing information to other mrouted routers, and to check whether a host is still an active group member.

The underlying TCP/IP stack must support ICMP to participate in IP multicasting. While IGMP defines a standard for communicating information, it does not define a standard for how the multicast information is propagated among multicast routers. Consequently, DVMRP enables multicast routers to efficiently communicate group membership information among themselves. DVMRP uses IGMP messages to carry routing and group membership information. DVMRP

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Contents Edition Manufacturing Part Number B2355-90777 AugustCopyright Notice WarrantyGovernment License Trademark Notices Page Contents Contents Index Contents Intended Audience HP-UX Release Name and Release IdentifierDocument Organization Chapter Description What Is in This DocumentPublishing History HP-UX Internet Services Administrator’s Guide Related DocumentationMbone FAQ Typographical ConventionsHP Encourages Your Feedback BoldVersion of HP-UX that you are using Overview Overview Dvmrp Protocol Mrouted Routing DaemonMulticasting Overview Endpoint Dvmrp TunnelDvmrp Tunnel Multicast IP Multicast Addresses Class D IP Multicast Address FormatMulticast Groups Mrouted Routing Daemon Gated Routing Daemon AdvantagesDeciding When to Use gated Routing Protocols Comparison of RIP and Ospf Protocols RIP OspfRIP Ospf Gated Routing Daemon Gated Routing Daemon Chapter Configuring mrouted Configuring mrouted How to Configure mrouted Configuration CommandsTunnel Multicast Network Example Configuration How to Configure mrouted How to Configure mrouted Starting mrouted Verifying mrouted Operation Displaying mrouted Routing Tables HUP Displaying mrouted Routing Tables Multicast Routing Support Tools Mrinfo ToolMap-mbone Tool Netstat ToolMulticast Routing Support Tools Chapter Configuring gated Configuring gated Configuration Overview Configuring gated Protocol statements follow Converting the Configuration File from 3.0 to Cp /etc/gated.conf /etc/gated.conf.30 Configuring the RIP Protocol RIP Protocol StatementDefault Range 1 Configuration Options Simple RIP Configuration Example of Simple RIP ConfigurationEnd Systems RoutersExample of a Large RIP Configuration RIP RouterMajor Router Cluster Node Isolated NodeRoot Server Single NodeCluster or Root Server Node Controlling RIP Traffic Major RouterConfiguring the RIP Protocol Configuring the Ospf Protocol Network Router Area Areas Defined in an Autonomous SystemArea Configuring the Ospf Protocol Planning Your Ospf Configuration Enabling Ospf Area To Network a 193.2.1.33 Border Router To Network B Defining AreasArea Border Router Configuration Example Networks Statement Network Configuration ExampleInterface Statement Configuring the Ospf Protocol Default None Multicast Router Interface Example Router 193.2.1.35 NetworkRouter Network 193.2.1.35 193.2.1.33 Internet 193.2.1.46 Range 0Non-Broadcast Router Interface Example Hellointerval value must be the same for all Ospf routers Configuring the Ospf Protocol Stub Areas Point-to-Point Router Interface ExampleRouter 193.2.1.1 193.2.1.2 Area Router 193.2.1.20 193.2.1.17 193.2.1.18 193.2.1.19Defining Backbones Area 15.13.115.156 Router a Router BAuthentication Authkey travis Authkey pepeCost Cost LAN 1 LAN 2AS External Routes AS Boundary Routers Only Default Configuring the Ospf Protocol Sample Ospf Configuration Internal Router Non-Stub AreaArea Border Router Internal Router Stub Area Accessing the Ospf MIB Configuring RDP RDP ServerRDP Client Server RDP ClientCustomizing Routes Specifying a Default RouterInstalling Static Routes Setting Interface States Specifying Tracing Options Files Option EffectRoute Type Preference Default Preference Values of RoutesSpecifying Route Preference BGP Specifying Route Preference Export Statement Importing and Exporting RoutesImport Statement Examples of import and export Statements Flag Effect Command Line Options for gatedStarting gated Verifying That gated Is Running 100Tracing gated Activity Troubleshooting gatedChecking for Syntax Errors in the Configuration File Operational User Interface for gated gdc 102Ospfmonitor Tool Gated Routing TableRipquery Tool 104 Common ProblemsProblem 1 gated does not act as expected Chapter 105 Problem 2 gated deletes routes from the routing table 106Problem 3 gated adds routes that appear to be incorrect Problem 4 gated does not add routes that you think it must 108Index 109110 111 112 TOS 113