We present a stateless defense against the neighbor discovery denial-of-service (ND-DoS) attack in IPv6. The ND-DoS attack consists of remotely flooding a target subnet with bogus packets destined for random interface identifiers; a different one for each malicious packet. The 128-bit IPv6 address reserves its 64 low-order bits for the interface ID. Consequently, the malicious packets are very likely to fall on previously unresolved addresses and the target access router (or leaf router) is obligated to resolve these addresses by sending neighbor solicitation packets. Neighbor solicitation packets are link layer multicast (or broadcast), and hence also forwarded by bridges. As a consequence, the attack may consume important bandwidth in subnets with wireless bridges, or access points. This problem is particularly important in the presence of mobile IPv6 devices that expect incoming sessions from the Internet. In this case, address resolution is crucial for the access router to reliably deliver incoming sessions to idle mobile devices with unknown MAC addresses. We propose a novel neighbor solicitation technique using Bloom filters. Multiple IPv6 addresses (bogus or real) that are waiting in the access router's address resolution queue are compactly represented using a Bloom filter. By broadcasting a single neighbor solicitation message that carries the Bloom filter, multiple IPv6 addresses are concurrently solicited. Legitimate neighbor solicitation triggering packets are not denied service. An on-link host can detect its address in the received Bloom filter and return its MAC address to the access router. A bandwidth gain around 40 can be achieved in all cells of the target subnet. This approach that we call compact neighbor discovery (CND) is the first bandwidth DoS defense that we are aware of to employ a bandwidth optimization.

This paper presents a new pairing protocol that allows two CPU-constrained wireless devices Alice and Bob to establish a shared secret at a very low cost. To our knowledge, this is the first software pairing scheme that does not rely on expensive public-key cryptography, out-of-band channels (such as a keyboard or a display) or specific hardware, making it inexpensive and suitable for CPU-constrained devices such as sensors.

Cellular telephones save power by switching to a low power or dormant mode when there is no active traffic. In dormant mode, the telephone periodically checks for a beacon, and if the beacon indicates that the phone has moved to a new paging area, the telephone performs a paging area update. Paging area update signaling requires considerably less power than is required to move an active traffic channel. When a call comes in, the network pages the telephone by flood signaling the paging area on a special channel, and the telephone brings up an active traffic channel. Recent work has attempted to extend paging to IP networks, in particular, networks running the Mobile IP mobility management protocol. In this paper, we compare mobile IPv6 and IP paging for dormant mode location updating. Simulations are presented for a typical macrocellular scenario and a hotspot scenario, where broadband microcells supplement the narrowband macrocells. The results show that Mobile IPv6 dormant mode location management is roughly comparable to IP paging.