Configuring RIP to Check the Validity of Update Packets

The check on RIP Update packets includes the check on zero fields in RIPv1 packets and the check on source addresses of RIP Update packets. The two types of check have different functions and applications.

Procedure

Configure the zero field check for RIPv1 packets.
1. Access the system view.
```
system-view
```
2. Configure a RIP process and access the RIP process view.
```
rip [ process-id ]
```
3. Configure the zero field check is configured for RIPv1 packets.
```
checkzero
```
  Certain fields in a RIPv1 packet must be 0s, and these fields are called zero fields. RIPv1 checks the zero fields on receiving a packet. If the value of any zero field in a RIPv1 packet is not 0, this packet is not processed.
  
  As a RIPv2 packet does not contain any zero field, configuring the zero field check is invalid in RIPv2.
Configure the source address check for RIP Update packets.
1. Access the system view.
```
system-view
```
2. Configure a RIP process and access the RIP process view.
```
rip [ process-id ]
```
3. Configure the source address check for RIP Update packets.
```
verify-source
```
  When receiving a packet, RIP checks the source address of the packet. If the packet fails in the check, it is not processed.
  
  By default, the source address check is enabled.