Oliver Gasser

Learn More
Until recently, relatively little was known about the characteristics of the SSH protocol on the Internet, until two larger studies analysed the cryptographic properties of SSH host keys and identified weaknesses in a number of SSH devices. However, there is no succinct comprehensive image yet how the SSH landscape looks like from the point of view of(More)
—Active network measurements constitute an important part in gaining a better understanding of the Internet. Although IPv4-wide scans are now easily possible, random active probing is infeasible in the IPv6 Internet. Therefore, we propose a hybrid approach to generate a hitlist of IPv6 addresses for scanning: First, we extract IPv6 addresses from passive(More)
Botnets are today the universal tool for malicious activities in the Internet. They can send out spam messages, host fairly redundant malicious webpages, perform DDoS attacks and do much more. Of course, researchers have therefore been trying to effectively find and shut down botnets as quickly as possible. The Domain Name System has become an important(More)
Out-of-band network management is becoming more and more popular amongst high tech companies since high availability of network services is becoming more and more important. Especially servers with built in out-of-band management capabilities are growing in numbers as the increasing demand in bandwidth forces companies providing web services to outsource(More)
Nowadays, Distributed Denial-of-Service (DDoS) attacks are a major threat for all sizes of networks. The number of attacks against companies and institutions steadily increased over the last years. Downtime of an enterprise network usually causes financial damage. Therefore, it is important to have mechanism for DDoS defense. In this paper, various DDoS(More)