\section{Authors' Addresses}

\begin{flushleft}
Elin Wedlund\\
Switchlab\\
Ericsson Telecom AB\\
S-126 25 Stockholm\\
SWEDEN\\
electronic mail: {\sf elin.wedlund@etx.ericsson.se}
\end{flushleft}

\begin{flushleft}
Wenyu Jiang\\
Dept. of Computer Science\\
Columbia University\\
1214 Amsterdam Avenue\\
New York, NY 10027\\
USA\\
electronic mail: {\sf wenyu@cs.columbia.edu}
\end{flushleft}

\begin{flushleft}
Henning Schulzrinne\\
Dept. of Computer Science\\
Columbia University\\
1214 Amsterdam Avenue\\
New York, NY 10027\\
USA\\
electronic mail: {\sf schulzrinne@cs.columbia.edu}
\end{flushleft}
