Complex sentence: For his PhD he worked at Institut Eurécom with Prof. Ernst Biersack, and at AT&T Labs (Shannon Laboratory, Florham Park, NJ) developing TCP/IP improvements for multi ‐ hop HTTP proxies.
Split into simpler sentences: For his PhD he worked at Institut Eurécom with Prof. Ernst Biersack. During his PhD he also worked at AT&T Labs (Shannon Laboratory, Florham Park, NJ) developing TCP/IP improvements for multi ‐ hop HTTP proxies.