C
HAPTER
21
| Unicast Routing
Configuring the Open Shortest Path First Protocol (Version 2)
– 559 –
Figure 352: Configuring OSPF
C
OMMAND
U
SAGE
u
OSPF looks at more than just the simple hop count. When adding the
shortest path to any node into the tree, the optimal path is chosen on
the basis of delay, throughput and connectivity. OSPF utilizes IP
multicast to reduce the amount of routing traffic required when sending
or receiving routing path updates. The separate routing area scheme
used by OSPF further reduces the amount of routing traffic, and thus
inherently provides another level of routing protection. In addition, all
routing protocol exchanges can be authenticated. Finally, the OSPF
algorithms have been tailored for efficient operation in TCP/IP
Internets.
u
OSPFv2 is a compatible upgrade to OSPF. It involves enhancements to
protocol message authentication, and the addition of a point-to-
multipoint interface which allows OSPF to run over non-broadcast
networks, as well as support for overlapping area ranges.
u
When using OSPF, you must organize your network (i.e., autonomous
system) into normal, stub, or not-so-stubby areas; configure the
ranges of subnet addresses that can be aggregated by link state
advertisements; and configure virtual links for areas that do not have
direct physical access to the OSFP backbone.
n
To implement OSPF for a large network, you must first organize the
network into logical areas to limit the number of OSPF routers that
actively exchange Link State Advertisements (LSAs). You can then
define an OSPF interface by assigning an IP interface configured on
this router to one of these areas. This OSPF interface will send and
receive OSPF traffic to neighboring OSPF routers.
backbone
normal
area
NSSA
isolated
area
stub
Autonomous System A
Autonomous System B
external network
Router
ABR
ABR
ABR
ABR
ASBR
ASBR
ASBR
virtual
link
Содержание DG-GS4826S
Страница 2: ...DG GS4826S DG GS4850S E012011 R01 F1 2 2 0 ...
Страница 4: ......
Страница 6: ...ABOUT THIS GUIDE 6 ...
Страница 60: ...SECTION I Getting Started 60 ...
Страница 72: ...CHAPTER 1 Introduction System Defaults 72 ...
Страница 90: ...CHAPTER 2 Initial Switch Configuration Managing System Files 90 ...
Страница 92: ...SECTION II Web Configuration 92 u Unicast Routing on page 539 u Multicast Routing on page 595 ...
Страница 137: ...CHAPTER 4 Basic Management Tasks Resetting the System 137 Figure 23 Restarting the Switch Regularly ...
Страница 138: ...CHAPTER 4 Basic Management Tasks Resetting the System 138 ...
Страница 204: ...CHAPTER 6 VLAN Configuration Configuring MAC based VLANs 204 ...
Страница 212: ...CHAPTER 7 Address Table Settings Clearing the Dynamic Address Table 212 ...
Страница 238: ...CHAPTER 9 Rate Limit Configuration 238 Figure 106 Configuring Rate Limits ...
Страница 268: ...CHAPTER 12 Quality of Service Attaching a Policy Map to a Port 268 ...
Страница 368: ...CHAPTER 14 Security Measures DHCP Snooping 368 ...
Страница 422: ...CHAPTER 15 Basic Administration Protocols Remote Monitoring 422 ...
Страница 466: ...CHAPTER 16 Multicast Filtering Multicast VLAN Registration 466 Figure 273 Showing All MVR Groups Assigned to a Port ...
Страница 487: ...CHAPTER 17 IP Configuration Setting the Switch s IP Address IP Version 6 487 Figure 285 Showing Reported MTU Values ...
Страница 488: ...CHAPTER 17 IP Configuration Setting the Switch s IP Address IP Version 6 488 ...
Страница 538: ...CHAPTER 20 IP Services Forwarding UDP Service Requests 538 ...
Страница 594: ...CHAPTER 21 Unicast Routing Configuring the Open Shortest Path First Protocol Version 2 594 ...
Страница 624: ...CHAPTER 22 Multicast Routing Configuring PIMv6 for IPv6 624 ...
Страница 638: ...CHAPTER 23 Using the Command Line Interface CLI Command Groups 638 ...
Страница 712: ...CHAPTER 26 SNMP Commands 712 ...
Страница 720: ...CHAPTER 27 Remote Monitoring Commands 720 ...
Страница 776: ...CHAPTER 29 Authentication Commands Management IP Filter 776 ...
Страница 876: ...CHAPTER 34 Port Mirroring Commands Local Port Mirroring Commands 876 ...
Страница 898: ...CHAPTER 37 Address Table Commands 898 ...
Страница 998: ...CHAPTER 41 Quality of Service Commands 998 ...
Страница 1060: ...CHAPTER 42 Multicast Filtering Commands MLD Proxy Routing 1060 ...
Страница 1078: ...CHAPTER 43 LLDP Commands 1078 ...
Страница 1088: ...CHAPTER 44 Domain Name Service Commands 1088 ...
Страница 1164: ...CHAPTER 47 IP Interface Commands IPv6 to IPv4 Tunnels 1164 ...
Страница 1260: ...CHAPTER 48 IP Routing Commands Open Shortest Path First OSPFv3 1260 ...
Страница 1304: ...SECTION IV Appendices 1304 ...
Страница 1310: ...APPENDIX A Software Specifications Management Information Bases 1310 ...
Страница 1343: ...DG GS4826S DG GS4850S E012011 R02 F1 2 2 0 ...
Страница 1344: ......