Introduction to routing strategy

 

Definition

Routing strategy It controls the route through a series of tools or methods “ Strategy ”. This strategy can affect route generation 、 Release 、 Selection, etc , And then affect the forwarding path of the message . Tools include ACL、route-policy、ip-prefix、filter-policy etc. , Methods include filtering routes , Set the properties of the route .

Purpose

stay IP In the network , The purpose of routing strategy mainly includes two aspects ： Filter the route information and modify the attributes of the route , As shown in the table 1 Shown .

Filter the routing information through the routing policy

chart 1  Filter the routing information through the routing policy  

Pictured 1 Shown ,SwitchA It is a dual uplink networking structure ,SwitchA From SwitchB and SwitchC Where routes are received separately . If SwitchA Only want to receive from SwitchB The routing , Instead of receiving from SwitchC The routing . In this case, we can consider SwitchA Configure routing policy , Allow from SwitchB The routing , Rejection comes from SwitchC The routing .

Modify the properties of the route through the routing policy

chart 2  Modify the properties of the route through the routing policy

Pictured 2 Shown ,SwitchA It is also a dual uplink network structure , however , because SwitchB The link here is more stable , A bit more bandwidth , So the user wants to use SwitchB The link here serves as the primary link ,SwitchC The link here serves as a backup link , When the primary link fails, the traffic will automatically switch to the standby link . In this case , You can use a routing policy , Will come from SwitchB The routing cost here is reduced , Will come from SwitchC Increase the routing cost here , In this way, the traffic will be automatically selected SwitchB The link here serves as the primary link ,SwitchC The link here serves as a backup link , Realize the primary backup of the route .

benefit

Routing policies have the following values ：

• Control the reception of routes 、 Release and introduce , Improve network security .

• Modify routing properties , Make reasonable planning for network data traffic , Improve network performance .