Dealing With Mobility-Caused Outdated Mappings in Networks With Identifier/Locator Separation

Abstract

In networks with identifier/locator separation, packets from a source to a destination are generally tunneled from the source’s ingress tunnel router (ITR) to the destination’s egress tunnel router (ETR). In addition, the source’s ITR often caches the destination’s identifier-to-locator mapping for a certain duration, called cache timeout, in order to avoid frequently querying mapping servers. When the destination moves from an old ETR to a new one, its identifier-to-locator mapping changes accordingly, which makes the destination’s identifier-to-locator mapping cached at some ITRs outdated. While several approaches have been proposed to address this issue, they either cannot deal with all types of outdated mappings cached at the ITRs or face the triangular routing problem. Accordingly, in this paper, we propose a timer-based pointer forwarding (TBPF) approach that can deal with all types of outdated mappings and avoid the triangular routing problem. We present numerical results to compare TBPF with existing approaches and show that TBPF is a very promising solution for dealing with outdated mappings.