[GNUnet-SVN] r27800 - msh/doc

[gnunet]

Author: harsha
Date: 2013-07-08 18:45:22 +0200 (Mon, 08 Jul 2013)
New Revision: 27800

Modified:
   msh/doc/msh.tex
Log:
- update doc; instance selection in rounds


Modified: msh/doc/msh.tex
===================================================================
--- msh/doc/msh.tex     2013-07-08 16:02:51 UTC (rev 27799)
+++ msh/doc/msh.tex     2013-07-08 16:45:22 UTC (rev 27800)
@@ -84,18 +84,25 @@
 
 While using \texttt{msh} remote hosts are addressed with their IP addresses.
 However, as the real communication is done through MPI, a mapping between the 
IP
-addresses of all the hosts where the instances run and the instances' MPI id 
has
-to be determined.  This mapping is given to the application as a file from 
which
-the application can refer by IP address the host for executing a remote 
command.
+addresses of all the hosts where the instances run and the instances' MPI ids
+has to be determined.  This mapping is given to the application as a file from
+which the application can refer by IP address the host for executing a remote
+command.
 
 The mapping is determined by having each instance verify the IP addresses of 
all
-other instances in $n$ rounds for $n$ allocated hosts.  Before beginning the
-verification rounds, all instances open a socket on their hosts with a randomly
-picked free port and bind to all the host's IP addresses.  In each round an
-instance learns about the IP addresses of other instance and verifies them by
-establishing TCP connections to the other instance's socket with one TCP
-connection for each of its IP address.  The TCP connections are started in
-parallel and in non-blocking mode.  This is depicted in 
Figure~\ref{fig:ip_map}.
+instances running on the allocated hosts.  The verification proceeds in rounds
+where each instance verifies IP addresses of several instances.  At the
+beginning of each round, every instance opens a socket bound to a random port
+and all available IP addresses on its host and sends the IP addresses to the
+instances for verification.  The set of instances $n$ to be contacted is
+determined by the current round $r$ and the round width $R$ such that 
+\begin{center}
+  $ n = \{i\in I | (r.R + 1) \le i \le (r.R + r)\} $
+\end{center}
+The instances verify the IP addresses of the sending instance by establishing
+TCP connections to the sender's listening socket with one TCP connection for
+each of the sender's IP addresses.  The TCP connections are started in parallel
+and in non-blocking mode.  This is depicted in Figure~\ref{fig:ip_map}.
 
 \begin{figure}[h]
   \centering