Exercises 6.7.2 Lab 6-2 Using the AS_PATH Attribute Lab Activity

Lab Exercise: Lab 6-2 Using the AS_PATH Attribute The International Travel Agency’s ISP has been assigned an AS number of 300. This provider uses BGP to exchange routing information with several customer networks. Each customer network is assigned an AS number from the private range, such as AS 65000. Configure ISP to remove the private AS numbers within the AS_Path information from CustRtr. In addition, the ISP would like to prevent its customer networks from receiving route information from International Travel Agency’s AS 100. Use the AS_PATH attribute to implement this policy.

In this lab, you will use BGP commands to prevent private AS numbers from being advertised to the outside world. You will also use the AS_PATH attribute to filter BGP routes based on their source AS numbers.

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Content 6.7 BGP Lab Exercises 6.7.3 Lab 6-3 Configuring IBGP and EBGP Sessions, Local Preference and MED Lab Activity

Lab Exercise: Lab 6-3 Configuring IBGP and EBGP Sessions, Local Preference and MED The International Travel Agency runs BGP on its SanJose1 and SanJose2 routers externally with ISP, AS 200. IBGP is run internally between SanJose1 and SanJose2. Your job is to configure both EBGP and IBGP for this internetwork to allow for redundancy.

In this lab, you will configure both IBGP and EBGP. For IBGP peers in this lab to correctly exchange routing information, the next-hop-self command must be used along with the Local-Preference and MED attributes. This is to insure that the flat-rate, unlimited-use T1 link is used for sending and receiving data to and from the AS 200 on ISP. The metered T1 should only be used in the event that the primary T1 link has failed. Traffic sent across the metered T1 link offers the same bandwidth of the primary link but at a huge expense. Ensure that this link is not used unnecessarily.

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Content 6.7 BGP Lab Exercises 6.7.4 Lab 6-4 BGP Route Reflectors and Route Filters Lab Activity

Lab Exercise: Lab 6-4 BGP Route Reflectors and Route Filters The International Travel Agency maintains a full mesh IBGP network that has quickly scaled beyond 100 routers. The company wants to implement route reflectors to work around the full mesh IBGP requirement. Configure a small cluster and observe how BGP operates in this configuration. Use IP prefix filters to control the updates between IBGP peers.

In this lab, you will configure IBGP routers to use a route reflector and a simple route filter.

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Content Summary The Internet has proven to be a valuable tool to many companies, resulting in multiple redundant connections to many different Internet service providers (ISPs). Border Gateway Protocol (BGP) is used by ISPs to move traffic between autonomous systems and is also used by individual companies who are multihomed to control path selections.