From 722ca30ad49f0b3a2726ad3620612407caed3596 Mon Sep 17 00:00:00 2001 From: "Achim D. Brucker" Date: Wed, 4 Jan 2017 14:44:15 +0000 Subject: [PATCH] Removed outdated citations. --- StatefulFW/VOIP.thy | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/StatefulFW/VOIP.thy b/StatefulFW/VOIP.thy index f11eddb..1940e77 100644 --- a/StatefulFW/VOIP.thy +++ b/StatefulFW/VOIP.thy @@ -47,9 +47,8 @@ text{* complicated example, namely Voice over IP (VoIP). VoIP is standardized by the ITU-T under the name H.323, which can be seen as an "umbrella standard" which aggregates standards for multimedia - conferencing over packet-based networks (for a good overview of the - protocol suite, see \cite{switch_basic}). H.323 poses many problems - to firewalls. These problems include (taken from~\cite{vtel}): + conferencing over packet-based networks. H.323 poses many problems + to firewalls. These problems include: \begin{itemize} \item An H.323 call is made up of many different simultaneous connections. @@ -60,8 +59,7 @@ text{* \end{itemize} Again we only consider a simplified VoIP scenario with the following - seven messages which are grouped into four subprotocols (see Figure - \ref{voip}): + seven messages which are grouped into four subprotocols: \begin{itemize} \item Registration and Admission (H.225, port 1719): The caller contacts its gatekeeper with a call request. The gatekeeper