A system and method for managing a route cache to reduce the risk of disruption from denial of service attacks. All traffic arriving on a front interface from local (on-link) nodes (e.g., neighbor nodes) can be treated normally. However, for packets arriving from remote (off-link) sources addressed to a given destination IP address, a single, shared route cache entry can be used. The source-address field in this entry can be zeroed-out since it will not be used for traffic coming from any one source. Similarly, for all packets going to off-link destinations through the front-interface, another single shared route cache entry can be created and used. The destination-address field in this entry can be zeroed out since it will not be used for traffic going to any one destination.