Introduction to lingke route table

This section describes the route tables of all routers, including the route table and FIB table. The route table is used to determine the route, and the FIB is used to forward the group, the route table will activate the route and send it to the FIB table. When the packet arrives at the router, it will forward it by searching the FIB table. I. Route table Type 1. routes found by Dynamic Routing Protocol 2. Static routes www.2cto.com 3. routes found by Link Layer Protocol (that is, directly connected routes) each forwarding entry in the FIB table indicates that the packet is sent to a certain CIDR block or a host should be sent through the physical interface of the router, and then the next vro in this path can be reached, or, it is not transmitted to the target host in the directly connected network through another vro.
Ii. Core Route 1. Core route table: The vro uses the local core route table for Route decision-making. The route table selects routes based on the priority and measurement values of various routing protocols. 2. Protocol route table: The table contains the routes found by the Protocol. Iii. FIB table operation process 1. After the route table selects a route table, the route table will activate the route and send it to the FIB table. When the packet arrives at the router, it will be forwarded by searching for the FIB table. 2. FIB table matching follows the longest matching principle. In the FIB table, the destination address of the packet matches the mask of each table in the FIB table in BIT logic. The obtained address matches the network address in the FIB table. Finally, select the longest matching FIB table item to forward the packet. Www.2cto.com
Iv. Route table content 1, including: destination mask pre cost. 2. mask: network mask. Together with the destination address, it identifies the IP address of the CIDR Block of the target host or router. 3. cost: Route overhead. When multiple routes arrive at the same destination have the same priority, the Minimum Route overhead will become the optimal route. 4. destination: destination Address. Identifies the IP address or destination network. 5. pre: identifies the priority of a route entry to an ip route table. There may be multiple routes arriving at a destination, but the existence of priority allows them to select a route with a higher priority for exploitation. 6. interface: output interface. This indicates that the IP packet will be forwarded from the router interface. 7. nexthop: Next IP address. Indicates the next router that the IP packet goes through.