Multihoming Scenario: Addresses Taken from One Provider
In this scenario (depicted in a moment in Figure 3-14), customers are connected to multiple providers. Customers are small enough that they need to take IP addresses from only one of their multiple providers, or they were allocated the addresses while they were single-homed. We will consider two ISPs (ISP1 and ISP2) and their customers: Onenet, Twonet, and Stubnet. For each domain, Table 3-6 lists the IP address ranges, corresponding aggregates, and providers. Figure 3-14. Ad..
1245. PPP Security As described in Chapter 17, “Synchronous Serial Links and Protocols,” PPP provides the capability to use PAP and CHAP for authentication, which is particularly useful for dial applications. Chapter 17 used only the default authentication method for CHAP/PAP—namely, the reliance on a locally configured set of username name password password commands. Cisco IOS supports the use of AAA authentication for PPP using the same general set of commands as used..
The link-state update packet, OSPF packet type 4, is sent in response to the link-state request packet and implements the flooding of LSAs. The link-state update packet carries a collection of LSAs one hop from its origin. Several LSAs can be included in a single update. Each LSA must be acknowledged. In response to the link-state update, a link-state acknowledgment packet is sent to multicast addresses on the networks that support multicast. If retransmission o..
The Cisco VPN Client for Windows supports two interfaces: CLI and GUI. This book will focus on the GUI interface of the 4.6 client. Once you have installed the client, go to Start > Programs > Cisco VPN Software Client > VPN Client to access the GUI. Sometimes the application is referred to as the "VPN Dialer," after the older 3.x application name. Operating Modes The VPN Client has two operating modes: • Simple Mode, shown in Figure 12-1 Figu..
Using DHCP to Dynamically Configure Router IP Addresses
The ip address dhcp configuration command allows the router to obtain the address information for an interface dynamically: Router1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router1(config)#interface FastEthernet0/1 Router1(config-if)#ip address dhcp Router1(config-if)#end Router1# Interface FastEthernet0/1 assigned DHCP address 172.25.1.57, mask 255.255.255.0 Router1# Prior to Release 12.2(..
