HP Routing Services -UX 11i v2 manual IP Multicast Addresses, Class D IP Multicast Address Format

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Overview

The mrouted Routing Daemon

In this ﬁgure, the mrouted router R1 receives a multicast packet from node M. Because R1 is conﬁgured as one end of a tunnel, R1 encapsulates the IP multicast packet in a standard unicast IP packet addressed to the mrouted router R2. The packet, now treated as a normal IP packet, is sent through the intervening nonmulticast network to R2. R2 receives the packet and removes the outer IP header, thereby restoring the original multicast packet. R2 then forwards the multicast packet through its network interface to node N.

	IP Multicast Addresses
	An IP Internet address can be either a 32-bit or a 128-bit address. Each
	host on the Internet is assigned a unique IP address. There are four
	classes of IP addresses: Class A, Class B, Class C, and Class D. Class D
	IP addresses are identiﬁed as IP multicast addresses. Class A, Class B,
	and Class C IP addresses are composed of two parts: a network ID
	(netid) and a host ID (hostid). Class D IP addresses are structured
	differently, as shown in Figure 1-2.
Figure 1-2	Class D IP Multicast Address Format
	0 1 2 3 4						31
		1	1	1	0		Multicast Group Address

The ﬁrst 4 bits (0 through 3) identify the address as a multicast address. Bits 4 through 31 identify the multicast group. Multicast addresses are in the range 224.0.0.0 through 239.255.255.255. Addresses 224.0.0.0 through 224.0.0.255 are reserved, and address 224.0.0.1 is permanently assigned to the all hosts group. The all hosts group is used to reach all the hosts on a local network that participate in IP multicasting. The addresses of other permanent multicast groups are published in RFC 1060 (Assigned Numbers, March 1990).

You can use IP multicast addresses only as destination addresses, and they must never appear in the source address ﬁeld of a datagram. Internet Control Message Protocol (ICMP) error messages are not generated for multicast datagrams.

Because IP Internet addressing is a software manifestation of the underlying physical network, you must map IP addresses to physical addresses that the hardware comprising the network understands.

Chapter 1

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Contents Manufacturing Part Number B2355-90777 August EditionGovernment License WarrantyCopyright Notice Trademark Notices Page Contents Contents Index Contents HP-UX Release Name and Release Identiﬁer Intended AudiencePublishing History What Is in This DocumentDocument Organization Chapter Description Related Documentation HP-UX Internet Services Administrator’s GuideTypographical Conventions Mbone FAQBold HP Encourages Your FeedbackVersion of HP-UX that you are using Overview Overview Multicasting Overview Mrouted Routing DaemonDvmrp Protocol Dvmrp Tunnel Multicast Dvmrp TunnelEndpoint Class D IP Multicast Address Format IP Multicast AddressesMulticast Groups Mrouted Routing Daemon Advantages Gated Routing DaemonDeciding When to Use gated Routing Protocols RIP Ospf Comparison of RIP and Ospf ProtocolsRIP Ospf Gated Routing Daemon Gated Routing Daemon Chapter Conﬁguring mrouted Conﬁguring mrouted Conﬁguration Commands How to Conﬁgure mroutedTunnel 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 Netstat Tool Multicast Routing Support ToolsMrinfo Tool Map-mbone 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 RIP Protocol Statement Conﬁguring the RIP ProtocolDefault Range 1 Conﬁguration Options Routers Simple RIP ConﬁgurationExample of Simple RIP Conﬁguration End SystemsRIP Router Example of a Large RIP ConﬁgurationSingle Node Major RouterCluster Node Isolated Node Root ServerCluster or Root Server Node Major Router Controlling RIP TrafﬁcConﬁguring the RIP Protocol Conﬁguring the Ospf Protocol Area Areas Deﬁned in an Autonomous SystemNetwork Router Area Conﬁguring the Ospf Protocol Planning Your Ospf Conﬁguration Enabling Ospf Area Border Router Conﬁguration Example Deﬁning AreasArea To Network a 193.2.1.33 Border Router To Network B Network Conﬁguration Example Networks StatementInterface Statement Conﬁguring the Ospf Protocol Default None Router 193.2.1.35 Network Multicast Router Interface ExampleNon-Broadcast Router Interface Example Range 0Router Network 193.2.1.35 193.2.1.33 Internet 193.2.1.46 Hellointerval value must be the same for all Ospf routers Conﬁguring the Ospf Protocol Router 193.2.1.1 193.2.1.2 Point-to-Point Router Interface ExampleStub Areas 193.2.1.20 193.2.1.17 193.2.1.18 193.2.1.19 Area RouterArea 15.13.115.156 Router a Router B Deﬁning BackbonesAuthentication Authkey pepe Authkey travisCost LAN 1 LAN 2 CostAS External Routes AS Boundary Routers Only Default Conﬁguring the Ospf Protocol Internal Router Non-Stub Area Sample Ospf ConﬁgurationArea Border Router Internal Router Stub Area Accessing the Ospf MIB RDP Server Conﬁguring RDPRDP Client RDP Client ServerInstalling Static Routes Specifying a Default RouterCustomizing Routes Setting Interface States Specifying Tracing Options Option Effect FilesSpecifying Route Preference Default Preference Values of RoutesRoute Type Preference BGP Specifying Route Preference Import Statement Importing and Exporting RoutesExport Statement Examples of import and export Statements Starting gated Command Line Options for gatedFlag Effect 100 Verifying That gated Is RunningChecking for Syntax Errors in the Conﬁguration File Troubleshooting gatedTracing gated Activity 102 Operational User Interface for gated gdcRipquery Tool Gated Routing TableOspfmonitor Tool Problem 1 gated does not act as expected Common Problems104 Chapter 105 106 Problem 2 gated deletes routes from the routing tableProblem 3 gated adds routes that appear to be incorrect 108 Problem 4 gated does not add routes that you think it must109 Index110 111 112 113 TOS