Bgp Advantages - HP 7102dl - ProCurve Secure Router Configuration Manual

IP Routing—Configuring RIP, OSPF, BGP, and PBR
Configuring BGP
15-68
The WAN router runs BGP to communicate with the connecting ISP router,
also called the ISP edge router. The ISP tunnels the routes advertised by the
local router through the Internet to the remote sites. Only ISP routers that
connect to routers at the private organization's remote sites can receive these
routes, which they then pass to the private routers. Routers internal to the ISP
run an internal routing protocol and do not receive the private routes.

BGP Advantages

BGP is not the only way to use your ISP to advertise routes or distribute private
routes through the Internet. You can also use static routing or RIP v2.
With static routing, you configure a default route on the local router to the ISP
router. The ISP manually configures routes to the private sites on its edge
routers directly connecting to these sites.
RIP v2 runs on the network between the private router and the ISP router. The
ISP edge routers then redistribute the static or RIP routes into BGP, which
runs on the ISP network. The ISP tunnels the routes through its network to
the remote sites, as it does with those discovered by eBGP.
Static routing and RIP are simple to configure, have low overhead, and are
well suited for medium-to-small networks with only one connection to an ISP.
However, BGP offers several advantages, particularly in more complex envi-
ronments:
Unlike routers using static routing, routers running BGP can automati-
cally respond to downed connections and changes in network topology.
Your organization can change its IP addressing without notifying your ISP.
(RIP v2 also offers this advantage.)
BGP can handle complex applications in which the private network
connects to multiple ISP routers or multiple ISPs. You can configure BGP
to balance loads among these connections.
BGP is the native protocol run by ISPs, which decreases problems caused
by redistributing static or RIP routes into BGP.
BGP is policy based, so you maintain tight control over the routes trans-
mitted and accepted.