Xiaobai dry goods! Detailed explanation of the difference between network engineering routing strategy and policy routing

1. Flow behavior control requirements

1.1. Control the reachability of network traffic

1.2. Ways to adjust network traffic

Regarding the above two flow control requirements, we can deal with it in two ways.
Routing strategy
. The reachability of traffic can be controlled by controlling routing entries (that is, the route termination filtering for admission and advertisement).
Strategic routing is
aborted before looking up the routing table. The act of controlling traffic (such as ACL)

2. Routing strategy
   2.1. The definition of routing strategy .
   A series of tools or methods are used to stop various control strategies
   on routing. It affects the occurrence, release, and selection of routing, and then affects the forwarding path of messages.

2.2. The purpose of the routing strategy

2.3. The role of routing strategy
Control the access, release and introduction of
routing to improve network security. Modify routing attributes, make reasonable plans for the suspension of network data traffic, and improve network functions

2.4. The completion mechanism of the
routing strategy The core content of the routing strategy is the filter. After the filter is used, a set of matching rules is defined

You can use the first 6 filters to define your own matching rules. Not only can you match the routing attributes, you can also change the routing attributes.

2.5. The calling relationship between the tools of the routing strategy

2.6. IP-Prefix List
2.6.1. The concept of IP-Prefix List
can accurately match the network number and prefix length at the same time. The
function and controllability are higher than ACL (ACL cannot match the mask/prefix length). The
prefix list cannot be used for data. Packet filtering

2.6.2. Obligation mechanism of IP-Prefix List

ACL, IP IP-Prefix, Route-Policy do not have the default rejection of the
matched route 2.6.3. Syntax rules of IP-Prefix List

2.6.4. Example of IP-Prefix List

First precisely match the previous network location, and then match the mask
2.7. Filiter-Policy is
a rare routing filtering tool that can only filter routes, not LSAs, and modify routing attributes.

Distance vector

Link appearance

2.8. Route-Policy
Route-Policy is a powerful and complex filter for route filtering and modification of route attributes
2.8.1. Route-Policy syntax rules

Route-Policy is composed of several nodes, and the relationship between nodes is "or".
Each node can have several if-macth and apply clauses.
If-match is between "and" relationship
2.8.2 Route-Policy Marriage rules

3. Strategic routing
   PBR: Policy-Based-Route, this technology breaks the traditional routing rules of the routing table, and can selectively forward data packets according to the strategic conditions defined by the administrator
   . 3.1. The difference between routing strategy and strategic routing
   

In the routing strategy, the rejected ones will not go through the
strategic routing, and the rejected ones will be forwarded normally.
3.2 The rules of strategic routing

Route-Policy is composed of several nodes, and the relationship between nodes is "or".
Each node can have several if-macth and apply clauses.
If-match is between "and" relationship

3.3. Local strategic routing
only works on the messages sent by the machine, but not on the forwarded messages

3.4. Interface strategic routing
only works on the forwarded packets, not on the packets sent by the machine

Configuration of interface strategic routing: completed through flow strategy technology
Flow strategy: associate flow classification and Sheng behavior, which is flow strategy, constitutes a "template" configuration method, the biggest advantage is that it can save configuration and support batch correction

Streaming strategy can only be deployed in the direction of entry