Mitigation of topology control traffic attacks in OLSR networks

Abstract

Abstract-The core of the Optimized Link State Routing (OLSR) protocol is the selection of Multipoint Relays (MPRs) as a flooding mechanism for distributing control traffic messages. A node in an OLSR network, selects its MPR set such that all two-hop neighbors are reachable through, at least, one MPR. However, if an MPR misbehaves during the execution of the protocol, the connectivity of the network is compromised. Additional coverage in the selection of the MPRs helps to mitigate the effect of control traffic attacks. RFC3626 defines the selection of MPRs with additional coverage. Nevertheless, the overhead of the network increases due to the added number of control traffic messages. In this paper, we propose an improved MPR selection with additional coverage. Every node selects, if it is possible, k + 1 disjoint MPR sets. The union of those sets, is a k-robust-MPR set. Thus, given a node, alternative paths are created to reach any destination two-hops away. We test both approaches against two kinds of adversaries misbehaving during the execution of the protocol. Our proposed MPR selection with additional coverage mitigates the effect of control traffic attacks by offering equivalent protection compared to the MPR selection with extra coverage presented in RFC3626, but reducing the overhead generated by redundant control information.

Mitigation of flooding disruption attacks in link state mobile ad hoc networks

“…Our first contribution deals with the effect of control traffic attacks in OLSR networks and the selection of MPR sets with additional coverage to mitigate their effect [23]. The MPR selection with additional coverage is presented in RFC 3626 [34]; we name it k-Covered-MPR selection.…”

“…In this chapter, we propose an improved MPR selection with additional coverage (cf., function fc-robust-MPR) [23] to mitigate the effect of traffic control message attacks. We compare our function against the MPR selection with additional coverage (cf., function kcovered-MPR) proposed in the RFC3626.…”

“…However, the overhead generated by the excessive number of TC and HTC messages reduces the performance of the network. This problem is addressed with an improved fc-Robust-MPR selection pre sented in [23] and detailed in Chapter 5. The fc-Robust-MPR set has two main properties:…”

“…However, the overhead due to the excessive number of TC messages reduces the performance of the network. This problem is addressed by the fc-Robust-MPR selection presented in [23], which balances security and traffic overhead. In OLSR, the…”

“…Additional coverage in the selection of MPRs, may help to reduce the time to detect changes in the topology due to mobility. This thesis is based on the work presented in [23,24,25].…”