IPv6 retains the use and function of multicast addresses as a major address class. IPv6 prefix FF00::/8 is allocated for all IPv6 multicast addresses. IPv6 multicast addresses are described in RFC 2373. The EIGRP for IPv6, OSPFv3, and RIPng routing protocols use multicast addresses to communicate between router neighbors.
The format of the IPv6 multicast address is described in Chapter 2, “Internet Protocol Version 6 (IPv6) Design.” Table 5-4 lists the common multicast addresses.
Table 5-4 Well-Known Multicast Addresses
| Multicast Address | Multicast Group |
| FF01::1 | All nodes (node-local) |
| FF02::1 | All nodes (link-local) |
| FF01::2 | All routers (node-local) |
| FF02::2 | All routers (link-local) |
| FF02::5 | OSPFv3 routers |
| FF02::6 | OSPFv3 DRs |
| FF02::9 | Routing Information Protocol (RIPng) |
| FF02::A | EIGRP routers |
| FF02::B | Mobile agents |
| FF02::C | DHCP servers/relay agents |
| FF02::D | All PIM routers |
Network Management Design
After a new network is designed, installed, and configured, it must be managed by the operations team. Network management tools are used to gather operating statistics and to manage devices. These network management devices use protocols such as SNMP and RMON to obtain information on network performance.
Statistics are gathered on WAN bandwidth utilization, router CPU and memory utilization, and interface counters. Configuration changes are also made through network management tools such as Cisco Prime. The ISO defines five types of network management processes that are commonly known as FCAPS:
- Fault management: Refers to detecting and correcting network fault problems
- Configuration management: Refers to baselining, modifying, and tracking configuration changes
- Accounting management: Refers to keeping track of circuits for billing of services
- Performance management: Measures the network’s effectiveness at delivering packets
- Security management: Tracks the authentication and authorization information
Network management is supported by the elements listed in Table 5-5.
Table 5-5 Network Management Elements
| Network Management Element | Description |
| Network management system (NMS) | Runs the applications that manage and monitor managed devices. |
| Network management protocols and standards | Used to exchange management information between the NMS and the managed devices. The key protocols and standards are SNMP, MIB, and RMON. |
| Managed devices | Managed by the NMS. |
| Management agents | Reside in the managed devices and include SNMP agents and RMON agents. |
The protocols and tools described in this chapter perform some of these functions. SNMP is the underlying protocol used for network management. Agents are configured in managed devices (routers) that allow the NMS to manage the devices. RMON is used for advanced monitoring of routers and switches. CDP is a Cisco proprietary protocol that enables the discovery of Cisco devices. NetFlow is a network monitoring solution that allows for greater scalability than RMON. Syslog allows system messages and error events to be gathered for review.