% $Id: conclusions.tex,v 1.7 2005/03/01 10:06:58 gokhale Exp $

\section{Concluding Remarks}
\label{sec:conclusions}

In this paper we discussed the resource tradeoffs for WSNs. We studied
the protocol performance against steady increase of sensor nodes and
sink size in the network. The contributions and lessons learned from
our work are twofold.  

\noindent {\bf 1. Effects of resource tradeoffs in sensor networks:}
We studied the effects of resource tradeoffs on network performance,
which indicated the following:
\begin{enumerate}
\item We show that increasing nodes per unit sensing area does not make
   the network mode redundant, instead this may lead to a fast
   depleting network which is counter productive. 
\item At increased network densities and sink sizes (number of sinks in
   the network), the energy consumption starts increasing very rapidly
   due to increased traffic that each node has to handle. This argues
   for an intelligent energy utilization mechanism which scales the
   network well as the above parameters. 
\end{enumerate}

\noindent{\bf 2. Proposed enhancements to protocols:} 
Based on our analysis, we propose the following improvements to the
two protocols studied. 
\begin{enumerate}
\item In Directed Diffusion (DD), we propose a local broadcast, which
   reduces redundant transmissions during broadcast
   operations. Further, performance improvement can be achieved by
   maintaining multiple paths instead of a single reinforced path, to
   reduce the energy depletion of the single path nodes. 
\item In Two-tier Data Dissemination (TTDD), we propose a new
      mechanism to dynamically change the 
   flooding area without changing the cell size {\em i.e.}, without
   having to reconstruct the grid. In the worst case, our approach
   gives a reduction of almost 50\% in the local (cell) flooding area. 
\end{enumerate}


