RIP VD algorithm protocol is implemented directly on the LAN, RIP protocol participants will be divided into active machine and the two motives. Driving machine outside path refresh messages broadcast its own initiative, be motivated to passively accept path refresh messages. Under normal circumstances, the gateway primary motivation is motivation for the hosts.
RIP provides the gateway every 30 seconds a VD outwardly broadcast packet, message information from the local routing table. VD RIP protocol packets, to a distance meter inn: sink with a predetermined network gateway directly connected to a post, a gateway was separated by two post ...... and so on. A path for the path from the gateway number (from the source unit to the sink unit) on. To prevent the long-term existence of routing loops, the RIP predetermined length of the path 16 is infinitely long path, which path does not exist. Therefore, a limited path length shall not exceed 15. It is this provision limits the use of the RIP, the RIP limited to small local area network points.
Path overhead processing for the same principle is employed preconceived. In specific applications, it may happen, the path going to the same network has several pieces of the same distance. In this case, no matter which path the gateway broadcast packets first come, who would adopt the path. Until the new path failure or a shorter path instead.
Outdated RIP protocol processing path is the use of two timers; timer time-out timer and garbage collection. All machines on the routing table of each item on the set two timers. Each add a new table to a corresponding increase in two timers. When a new route is installed into the routing table, the time-out timer is initialized to 0, and starts counting. Whenever the received message contains the RIP routing, time-out timer will be reset to zero. If no message is received containing the RIP routing within 180 seconds, the route metric is set to 16, the timer is started garbage collection route. If 120 seconds have passed, RIP did not receive the message route, the route is deleted from the routing table. If the garbage collection prior to the timer 120 seconds, the received message contains the routing, the timer is cleared. Routed is mounted to the routing table.