From 1997 to 2000, he worked in the Mobile Communications Division of Siemens, Munich, Germany. He initially researched network design algorithms and performance evaluation techniques for GSM and UMTS networks. Later, he designed system architectures for Third and Fourth Generation wireless communication systems.
From 2000-2002, Claus was the main person responsible for all IP networking related research efforts at the Tellabs Research Center, Cambridge, Massachusetts. He led research projects and performed research that examined MPLS technology, quality-of-service-problems in the Internet, call admission control algorithms, optical switching technologies, packet switch architectures, and media gateways. His work also focused on the mathematical modeling and optimization of high-speed networks.
Since 2002, he is a Research Manager and Senior Scientist at Dolby Laboratories, San Francisco, California. He guides and performs research on multimedia digital signal processing, multimedia streaming technologies, home networking technologies, digital content security, and the application of discrete optimization techniques to problems in digital signal processing.
He is the author or co-author of numerous publications and patents in diverse areas of research. A native German speaker, he is also fluent in Mandarin, English, French, Spanish, Italian, and Portuguese.