Segmenting the AS with Multiple Regions Separated by EBGP
If flexible policies are required between regions to direct traffic accordingly, for instance, each region can be represented as a separate autonomous system. EBGP operates between ASs, and IBGP is run within each AS. You can use a separate IGP if there is an additional requirement for a dynamic routing protocol to establish reachability between EBGP peers. Figure 9-15 illustrates this AS segmentation method. Figure 9-15. Multiple Regions Separated by EBGP At first gl..
Route Exchange and BGP Decisions with Confederations
Even though routes are exchanged between sub-ASs of a confederation via EBGP, all the IBGP rules still apply in order for the whole AS to still behave as a single routing domain. The EBGP NEXT_HOP is still carried within the AS, as is the MED and LOCAL_PREF values. As far as the BGP decision algorithm, the only changes are in the way BGP routes to outside the confederation compared to how BGP routes inside the confederation. Without confederations, EBGP routes are preferred ..
Secure Shell and Cisco IOS SSH
Secure Shell (SSH) is a protocol that provides a secure connection to a router. Cisco IOS supports version 1 and 2 of SSH, which enables clients to make a secure and encrypted connection to a Cisco router. Cisco refers to this SSH support as Cisco IOS SSH. Before SSH was implemented, the only form of security available when accessing devices such as routers was Telnet username/password authentication, which is clearly visible with a network sniffer. Telnet is insecure because..
The finger command is a simple utility that allows you to do the equivalent of a show users command on a remote router. Unix computers generally have a standard finger program that you can run as follows: Freebsd% finger @Router1[Router1] Line User Host(s) Idle Location ..
Frame Relay Forum Implementation Agreement Document Number FRF.5
The functional specifications of network interworking between Frame Relay and ATM are defined in the Frame Relay Forum Implementation Agreement Document Number FRF.5. FRF.5 describes the implementation agreement on PVC network interworking between Frame Relay and ATM protocols, jointly agreed upon by the Frame Relay Forum and the ATM Forum. The complete FRF.5 documentation can be downloaded from the Frame Relay Forum's web site address at http://www.mplsforum.org/frame/Approv..
