Changing the Aggregate's Attributes

In some situations, changing the aggregate's attributes is required. The example in this section shows one scenario in which this could be useful. As you have already seen, the aggregate can carry information about its individual elements if configured with the AS_SET option. If one or more of the routes forming the AS_SET aggregate are configured with no-export community attribute, the aggregate itself will carry the same attribute. This will prevent the aggregate from bein..

Application Authentication and Privacy

Many of the application layer protocols mentioned in this chapter have built-in authentication through the use of a basic password mechanism. However, many of these protocols—for instance, Telnet, FTP, and TFTP—send the usernames and passwords in clear text. Some of the more recently defined or updated protocols provide stronger security. For example, Secure Shell (SSH) provides an alternative to Telnet but with strong authentication and privacy. SSH was originally inten..

IOS XR Basic EIGRPv6 Configuration On PE: Example

The following example shows how to configure EIGRP with a policy that filters incoming routes. This is a typical configuration for a router that has just one neighbor, but advertises other connected subnets.   router eigrp 100    vrf ABC     address-family ipv6       router-id 10.10.9.4       log-neighbor-changes       log-neighbor-warnings    &nbs..

PPP Layer 2 Payload Compression

Cisco IOS software supplies three different payload compression options for PPP, namely Lempel-Ziv Stacker (LZS), Microsoft Point-to-Point Compression (MPPC), and Predictor. Stacker and MPPC both use the same underlying Lempel-Ziv (LZ) compression algorithm, with Predictor using an algorithm called Predictor. LZ uses more CPU and less memory in comparison to Predictor, and it typically results in a better compression ratio. Table 17-7 summarizes some of the key points regar..

Wide-Area Networks and Technologies

Wide-area network (WAN) technologies are characterized as networks covering a broad geographical area. These technologies use common carrier facilities. On a seven-layer model, they operate on the physical, data link layer. WANs are divided into three types of links: Point-to-point(leased line)— There are several common protocols used in these links—the most common are Point -to Point Protocol (PPP), Synchronous Data Link Control (SDLC), and High-Level Data Link Control..