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- Changing the way of RREQ and RREP processing, dynamically changing txpower of the nodes under ns-2
Sir,
I am trying to do a improve the performance of wireless sensor network in three steps.
1)AODV modification: Changing the way of RREQ and RREP processing and increasing and decreasing TTL in a dynamic fashion.
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2.Incorporating ideas of GAF protocol by doing a better wake-up Scheduling algorithm
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3)By dynamically changing txpower of the nodes.
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1)AODV modification:Changing the way of RREQ and RREP processing and increasing and decreasing TTL in a dynamic fasion.
There are so many probabilistic RREQ and RREP handling methods implemented for really improving AODV similar to this idea. But for your information, the idea that you presenting will not improve the performance of AODV in any way (it will just increase the overhead in high-density network because you are increasing ttl in your idea – it will just increase the routing overhead and overall message overhead)
2.Incorporating ideas of GAF protocol by doing a better wake-up Scheduling algorithm
What you are presenting is a nothing but “same old wine in a new cup” – every wake-up scheduling algorithm will do the same in all most same way – ( I mean there is no point in your logic for any improvement better than existing algorithms)
In a “seemingly genuine GAF implementation” that you may see in a published literature, if you see their published code, then you can find that they are simply getting the location information and grid information as follows:
((MobileNode *)thisnode)->getLoc(&x, &y, &z);
gid_ = God::instance()->getMyGrid(x,y);
It means that they didn’t address the way in which the location of nodes will be resolved in a real world scenario.
If GAF is meant for WSN, then getting location information using GPS like functionality is a also a costly thing.
Further, you can not maintain grid membership and other grid information without additional message overhead.
But in the above mentione code they are just getting them from GOD object – In real implementation there will not be any global location from which you can get those information without any additional message overhead (like using a location information server).
What I am telling is: what you “see” as a working GAF implementation is nothing but fake work.
As far as I know there is no genuine, fully working implementation available for ns2.
3 By dynamically changing tx powor of the nodes.
There are so many papers in the published literature that are claiming that they reduced energy by dynamically changing tx power. But most of them were fake (trust me). You will need a better understanding to realize this as fact.
Anyway I hereby try to explain it to understand its significance :
For example, if you will need 0.01 w of energy to transmit a packet up to 100 meters, and you will need another 0.01 w to relay the packet to another 100 meters.
But if you try to transmit the packet for 200 meters, then you can not do it with 0.02 w. You will need higher than 0.02 watt. It is the nature of radio waves.
For example, if we need to transmit a packet up to 200 meters, then it may need (for example) 0.03 w. But if you do it in two steps (I mean two hops) with 0.01 watt, then totally you will need only 0.02 w. It is actually true.
But “reducing tx power technique” under high-density MANET or WSN will never practically work. Because, if you increase the hops, then it will increase the number of broadcasts. The increase in broadcasts will lead to more collisions and re-transmissions – It will lead to a high end to end delay and very poor throughput. So, there will be a lot of RREQs and RREPs in the network and will actually consume much power in discrete steps to find route in the large multihop network.
Since there will be a considerable increase in both transmissions, as well as receptions (because in wireless network, if one transmits, all the neighbors will receive it (yes receiving of too much packets also drain the batteries)
So, as per your imaginations, you can not reduce the overall energy consumption of network by reducing or increasing power.
So simply the things that you are telling in (3) will not improve performance in any way or reduce the overall energy consumption of the network (you may need to do lot of genuine experiments to really understand what I am trying to say).
You may see a lot of such idiotic ideas in reputed journal papers. Simply, they are all nothing but manipulated, fake works (or only work with some funny network constraints – and simply will not give improvement under real networking condition).
Charles Pandian