be established in the AS, increasing operation and maintenance costs. BGP confederations can
be configured to address this problem.
On the network shown in
, IBGP full-mesh connections must be established between
all the devices in AS 200 to ensure link connectivity. It is costly to establish a full-mesh network
because there are multiple BGP devices in AS 200. Confederations can be configured in AS 200
to reduce the number of IBGP connections to be established. After confederations are configured,
AS 200 is divided into three sub-ASs: AS 65001, AS 65002, and AS 65003. AS 65001 establishes
EBGP connections with AS 65002 and AS 65003. The three routers in AS 65001 establish IBGP
full-mesh connections with each other. As a result, the number of IBGP connections in AS 200
is reduced, and operation and maintenance costs are reduced.
Figure 8-35
Networking diagram for configuring confederations
POS1/0/0
200.1.1.1/24
AS 65002
RouterB
POS1/0/0
20.1.1.2/24
RouterC
AS 65003
POS1/0/0
20.1.2.2/24
POS3/0/0
20.1.2.1/24
AS 65001
RouterD
POS2/0/0
20.1.5.1/24
RouterE
POS2/0/0
20.1.5.2/24
POS1/0/0
20.1.3.2/24
POS4/0/0
20.1.3.1/24
POS5/0/0
20.1.4.1/24
POS1/0/0
20.1.4.2/24
RouterA
AS 200
RouterF
AS 100
GE2/0/0
9.1.1.1/24
POS1/0/0
200.1.1.2/24
POS2/0/0
20.1.1.1/24
Configuration Roadmap
The configuration roadmap is as follows:
1.
Configure a BGP confederation on each router, divide AS 200 into three sub-ASs: AS
65001, AS 65002, and AS 65003, and configure AS 65001 to establish EBGP connections
with AS 65002 and AS 65003 so that the sub-ASs can communicate with each other.
2.
Establish IBGP full-mesh connections between the devices in AS 65001 so that the devices
can communicate with each other.
3.
Establish an EBGP connection between AS 100 and AS 200 so that the two ASs can
communicate with each other.
Data Preparation
To complete the configuration, you need the following data:
HUAWEI NetEngine80E/40E Router
Configuration Guide - IP Routing
8 BGP Configuration
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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