VRRP as a protocol specifies certain rules to regulate the behavior of the artifacts implementing the protocol. Some of the rules apply to the transmission and reception of the VRRP messages. In this section we'll discuss these message exchange rules.
The following MUST be verified at the VRRP packet reception:
IP TTL is 255.
VRRP version is 2.
The packet is complete.
The checksum is correct.
VRID is configured on the receiving interface.
The recipient is not the IP address owner.
The authentication type matches the configured type.
After verifying the type of authentication, the VRRP router must perform the authentication using the specified method. As indicated, these verifications and the authenticity ...