Learn More
Secure communication is very important in computer networks and authentication is one of the most eminent preconditions. However, common authentication schemes are not applicable in ad hoc networks because public key infrastructures with a centralized certification authority are hard to deploy there. We propose and evaluate a security concept based on a(More)
Future road communication scenarios are expected to deploy a radio ad hoc communication technology for the transmission of data between vehicles. Such ad hoc networks are able to support low latencies and cost efficiency, which is very important for, e.g., safety related applications. In addition to vehicle-to-vehicle communication, users also will be(More)
Vehicular multi-hop ad hoc networks (VANETs) are an important technology for future developments of vehicular communication systems. Vehicles are able to exchange information within these networks without the need of installing any infrastructure along the roadside. VANETs can be used to improve the road safety by e.g. warning drivers about accidents in(More)
In our demonstration we present an implementation of DTN for embedded systems and demonstrate how a WLAN access point can be turned into a stand-alone DTN-node for mobile applications. The modular software design of "IBRDTN" is centered on the efficient use of resources and interoperability with the DTN2 reference implementation. Our modules comprise a DTN(More)
In this paper we present IBR-DTN, a lightweight, modular and portable Bundle Protocol implementation and DTN daemon. IBR-DTN is especially suited for embedded platforms, which allows to leverage the benefits of a fully compliant Bundle Protocol daemon in cost sensitive distributed sensing applications. We line out IBR-DTN’s extensible software architecture(More)
In this paper we analyse different factors affecting players' perception and performance in multiplayer games. We introduce a mean opinion score metric borrowed from the subjective analysis of audio and video content to classify the player's perceived game quality. With a survey we investigated the player's view on network latency for a variety of games.(More)
Large scale video-on-demand systems require that the servers offering the video retrieval and playback services are arranged as a distributed system in order to support a large number of concurrent streams. If such a system is hierarchical, an end-node server handles the requests from a particular area, the next server in the hierarchy takes the request(More)
Resource reservation in advance can be a useful extension for a reservation-based communication service, if certain users are willing to pay additional charges to overcome the blocking probability of a communication network. Existing proposals for advance reservations restrict service flexibility by technically enforcing a certain subset of service(More)