Implementing a fully distributed certificate authority in an OLSR MANET

Abstract

OLSR (optimal link state routing) is one of the four base routing protocols being considered for use with MANETs (mobile ad hoc networks) by the lETF's MANET working group. OLSR belongs to the proactive class of routing protocols in which the connection setup delay is minimized at the expense of the heavier control traffic load on the wireless channel. Existing IETF draft proposals on OLSR does not yet address security issues. Although a PKI (public key infrastructure) based security is deemed more appropriate for MANETs including OLSR MANETs, care should be taken to ensure that such an infrastructure does not add to the already heavy control traffic load in OLSR and, as much as possible, the existing OLSR control packets are utilized to support such infrastructures as well. In this paper we describe our approach in which a PKI is tightly coupled with an OLSR MANET at the network layer level and the OLSR control packets are leveraged to support various security related activities as well. We have implemented a fully distributed CA (certificate authority) and integrated it with an existing implementation of OLSRv4 (OLSR for IP version 4). Intricate details of our implementation are presented to develop insights into the key aspects of the proposed solution.