WALS-DA: A Refined Label Switching Framework for Directional- and Hybrid-Antennas MANETs

The original Wireless Arithmetic Label Switching (WALS) framework is unsuitable for MANETs with directional antennas. To overcome this limitation, we propose WALS-DA (Wireless Arithmetic Label Switching with Directional Antennas), a revised framework designed for compatibility with such environments. In WALS-DA, prime keys are no longer preassigned to individual nodes but are dynamically generated for each edge (virtual link) between adjacent nodes directional antennas. Unlike WALS, which relies on node-keys, WALS-DA employs edge-keys (a.k.a. link-keys), enabling intermediate nodes to identify specific next-hop neighbors by matching edges (directional antennas) through multiple modulo operations. To ensure backward compatibility, we also explore a hybrid scenario incorporating both omni-directional and directional antennas. Although WALS-DA introduces slightly higher label overhead compared to WALS, it remains a promising solution for specialized MANET deployments while highlighting key open issues for future research.