Rts Threshold Adalah
I disagree that “if you don’t take a hidden node problem then changing the RTS threshold won’t better performance.” Using CTR/RTS e’er lowers the chances of data collisions. Since every data collision causes information corruption and thus requires data to exist re-sent, less collisions means less re-sending of data and less re-sending of data can largely improve your WiFi performance; of course just if there is a notable amount of collisions in your network.
To explain the details: A node always has to wait for a certain menstruum of time and sense the aqueduct for possible transmissions prior to stating an own one. Merely if it doesn’t sense any transmissions, it may showtime an own one. Without RTS/CTS, this transmission is directly a data transmission. If now two nodes both have the same idea and commencement a data transmission about at the same fourth dimension, then these transmissions will collide. The result is, that neither transmission makes it anywhere as all received information will be corrupted for all other node and the AP.
If RTS/CTS is used, the transmission starts with a RTS packet beingness sent by the node afterwards the sensing. Only if that RTS request is answered past a CTS reply, a information transmission is started. Of course, if ii nodes desire to transmit at the same time, their RTS requests can likewise collide with the aforementioned negative consequence that no RTS is received at all. The deviation is, the entire network volition recover much faster from a RTS standoff than it will from a data collision. So a RTS collision is less harmful to the entire network operation than a data collision.
The downside is that RTS/CTS itself requires some network bandwidth on its own and it introduces new sensing times during that no other data transmissions or RTS/CTS transmissions may take identify. To brand things even worse, of course RTS/CTS e’er has to be performed using the slowest speed the network supports equally otherwise nodes simply supporting this speed won’t run into it. So basically you can say that RTS/CTS ever lowers the theoretical throughput of your entire network, notwithstanding if your network suffers past lots of collisions, either past the hidden node problem (which tin can also be caused by nodes from other networks just using the same channel as your network) or because your WiFi is crowded (as more nodes increment the chance for random collisions), it may in fact increase the actual throughput. Non the number of hidden nodes, the number of collisions is the of import cistron here, no matter how they are acquired.
I read a study (I volition update and add a link here once I was able to discover it over again), that suggests that unless your network is really small (less than maybe half dozen nodes and covering only a pocket-sized expanse) and not isolated from other networks using the same channel, using RTS/CTS almost always has a rather positive effect in do. So why the threshold value? If sending the data would take as much fourth dimension as a RTS/CTS handshake would take, there is little proceeds on using RTS/CTS, since whether the network has to recovery from a very small data collision or from a RTS standoff won’t make much difference. The meliorate recovery from from RTS collisions is because RTS packets are very modest whereas data packets are usually not. Only for very modest data packets, RTS/CTS just adds overhead for no practical gain.
And now you also know how a fragmentation threshold tin can improve network performance. On the one hand it limits the size of packets sent and every bit explained above, the smaller the packet in a standoff, the faster the network will recover from it. And on the other hand, if at that place was a standoff, just the fragment affected by it needs to be re-sent, not the entire packet. Withal, every fragment sent has an overhead of its own, then the more than fragments existence sent, the more than overhead that volition add and overhead is basically wasted bandwidth that could as well have been used for data transmissions instead.
Rts Threshold Adalah