HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual page 691

Customer
Network 1
Network 3
Figure 13-17. Balancing Loads between a Connection to Two Neighbors
You can also attempt to manually balance outbound traffic by having the
router accept certain routes from one neighbor and the remaining routes from
another. (See "Load Balancing Outgoing Traffic by Preventing an Interface
from Learning Specific Routes" on page 13-84.)
Balancing Inbound Traffic. Similarly, you can attempt to manually balance
inbound traffic by having the router advertise certain networks to one neigh-
bor and other networks to the other neighbor.
You configure which routes the router accepts and advertises by configuring
prefix lists and applying them to neighbors. Apply a prefix list to outbound
data to restrict the advertisement of certain routes; apply a prefix list to
inbound data to prohibit the router from accepting a route. See "Creating
Prefix Lists: Configuring Filters for Route Exchange" on page 13-78.
While an inbound filter can work fairly well for balancing outbound traffic,
advertising different routes to different neighbors may not balance inbound
traffic as effectively. You will always find it more difficult to load balance
inbound traffic because you cannot control your ISPs' policies.
IP Routing—Configuring RIP, OSPF, BGP, and PBR
Router A
Network 2
Router B
Network 4
Configuring BGP
ISP
ISP
ISP
13-77