Erweiterung von X für digitale Filme. - Ralf Keller; Bernd Lamparter; Wolfgang Effelsberg (Prax. Inf.verarb. Kommun., 1992)

Application layer issues for digital movies in high-speed networks. - Wolfgang Effelsberg; Bernd Lamparter; Ralf Keller (Architecture and Protocols for High-Speed Networks, 1993)

Erweiterung des X11-Servers zur digitalen Bewegtbilddarstellung. - Ralf Keller (Kommunikation in Verteilten Systemen, 1993)

MCAM: An Application Layer Protocol for Movie Control, Access, and Management. - Ralf Keller; Wolfgang Effelsberg (ACM Multimedia, 1993)

Performance Bottlenecks in Digital Movie Systems. - Ralf Keller; Wolfgang Effelsberg; Bernd Lamparter (NOSSDAV, 1993)

Implementing Movie Control, Access and Management - From a Formal Description to a Working Multimedia System. - Ralf Keller; Stefan Fischer 001; Wolfgang Effelsberg (ICDCS, 1994)

Architektur und Implementierung eines Anwendungsprotokolls für digitale Filme. - Ralf Keller (Kommunikation in Verteilten Systemen, 1995)

Quality of Service Mapping in Distributed Multimedia Systems. - Stefan Fischer 001; Ralf Keller (MMNET, 1995)

Effiziente Verarbeitung von multimedialen Datenströmen in Window-Systemen. - Ralf Keller; Wolfgang Effelsberg (Informationstechnik Tech. Inform., 1995)

XMovie: Architecture and Implementation of a Distributed Movie System. - Ralf Keller; Wolfgang Effelsberg; Bernd Lamparter (ACM Trans. Inf. Syst., 1995)

Anwendungsprotokolle für verteilte Multimedia-Systeme. - Ralf Keller (Shaker, 1996)

Electronic Commerce in Deutschland und weltweit: Neue Zahlungssysteme und ihre Anwendungsgebiete. - Konrad Wondra; Ralf Keller; Ian Herwono; Fiona Williams (Prax. Inf.verarb. Kommun., 1998)

Wireless ATM for broadband multimedia wireless access: the ATMmobil project. - Ralf Keller; Bernhard Walke; Gerhard P. Fettweis; Gert Bostelmann; Karl Heinz Möhrmann; Christoph Herrmann; Rolf Kraemer (IEEE Wirel. Commun., 1999)

On Integrating Differentiated Services and UMTS Networks. - Jörg Diederich 001; Thorsten Lohmar; Martina Zitterbart; Ralf Keller (LCN, 2000)

Adaptive mobile applications over cellular advanced radio. - Ernö Kovacs; Ralf Keller; Thorsten Lohmar; Rainer Kroh; Albert Held (PIMRC, 2000)

Traffic Phase Effects with RED and Constant Bit Rate UDP-Based Traffic. - Jörg Diederich 001; Thorsten Lohmar; Martina Zitterbart; Ralf Keller (QofIS, 2000)

Convergence of cellular and broadcast networks from a multi-radio perspective. - Ralf Keller; Thorsten Lohmar; Ralf Tönjes; Jörn Thielecke (IEEE Wirel. Commun., 2001)

Convergence of Broadcast and New Telecom Networks. - Ralf Keller; Thorsten Lohmar; Ralf Tönjes; Jörn Thielecke (Wirel. Pers. Commun., 2001)

Realization of a push service for Media Points based on SIP. - G. Plitsis; Ralf Keller; Joachim Sachs (MWCN, 2002)

Flow-control for multi-access systems. - Ralf Tönjes; Thorsten Lohmar; Marc Vorwerk; Ralf Keller (PIMRC, 2002)

Multi-Access in Future Generations. - Ralf Keller; Ralf Tönjes (Wirel. Pers. Commun., 2003)

Support of Multicast Services in 3GPP. - Thorsten Lohmar; Henning Wiemann; Frank Hundscheidt; Michael Meyer; Ralf Keller (Prax. Inf.verarb. Kommun., 2004)

Integration of media point system in UMTS to provide session handover for SIP-based multimedia services. - Ian Herwono; Joachim Sachs; Ralf Keller (PIMRC, 2005)

Provisioning and performance of mobility-aware personalized push services in wireless broadband hotspots. - Ian Herwono; Joachim Sachs; Ralf Keller (Comput. Networks, 2005)

Mobile Network Evolution - "The Return of the Pipe". - Ralf Keller; Fredrik Alriksson; Zoltán Richard Turányi; György Miklós (Wirel. Pers. Commun., 2005)

Voice Call Continuity - A Novel Mobility Scheme for Voice on Call Control Level. - Ralf Keller; Marc Vorwerk; Colin Barschel (VTC Fall, 2006)

IP basierte mobile Systeme (IP based Networks). - Ralf Keller (it Inf. Technol., 2006)

ScaleNet - Converged Networks of the Future (ScaleNet - Konvergente Netze der Zukunft). - Matthias Siebert; Bangnan Xu; M. Grigat; Erik Weiss; Nico Bayer; Dmitry Sivchenko; Thomas-Rolf Banniza; Klaus Wünstel; Stefan Wahl; Rolf Sigle; Ralf Keller; Armin Dekorsy; et al. (it Inf. Technol., 2006)

Network Virtualization: A Viable Path Towards the Future Internet. - Norbert Niebert; Ibtissam El Khayat; Stephan Baucke; Ralf Keller; René Rembarz; Joachim Sachs (Wirel. Pers. Commun., 2008)