A virtual router is a logical entity managed by VRRP that acts as a default router for hosts on a shared LAN. It consists of a Virtual Router Identifier (VRID) and a set of associated IP addresses (or an address) across a common LAN. A VRRP router can be the backup for one or more virtual routers.
The purpose of supporting multiple IP addresses within a single virtual router is for multi-netting. This is a common mechanism that allows multiple local subnet attachments on a single routing interface. Up to four virtual routers are possible on a single Nokia IP interface. The virtual routers must be in the same subnet. Each virtual router has its own VRID, state machine, and messaging instance.