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Problem ID: BGP2L
Submission Date: October 12, 1998
Submitted By: Jon Whitton


Large national company with internal Cisco
network running EIGRP require redundant Internet access.

Assume redundancy must be achieved by using Cisco routers
and not advanced proxy servers or other solution.

They have a good deal for 1 T3 circuit
and can back this up to another ISP using a T1
circuit. There are two BGP4 boundary routers at either end
of the country.

Politics dictate they want to use the T3 circuit for
in and outbound traffic with the T1 solely
for redundancy.

Both ISPs are willing to give full BGP4 feeds and
the company has a legal BGP4 AS number.


a) How can the routing be forced down the T3 pipe?

b) What protocols should be used between the two external
BGP routers.
Assume the internal network is well designed but not
fully meshed.

c) How can the company load balance the data between the T3 and T1?
Assume only external BGP4 is available and both feeds are via
separate ISPs with different legal AS numbers.

d) What would the advantages/disadvantages of using one ISP
who would give a EIGRP or OSPF routing feed?

e) Specify the two routers and modules and IOS feature sets required.
What memory is required?

For the adventurous try setting this up in a lab senario!