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I'm trying to configure a home server, but the connection is very unstable. I looked at the WLAN adapter's (USB) settings and found out that the speed never goes above 72 Mbps (I mean Mbps not MB/s). On the box of this adapter is written "300 Mbps USB WLAN adapter". On the box of the router is written "150 Mbps" and my laptop (also my sister's and my dad's laptops and my mom's PC) is with 150 Mbps. However, when I took a look on them the speed never goes above 68 Mbps. I'm wondering if the problem could be in the router, because I turned off all the devices in the network and the speed remains the same?

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The router may not be configured correctly or there may not be two available adjacent channels. – David Schwartz Nov 8 '12 at 15:09
Does the channels affect the speed. Because I tried to change them, It was set to Auto Select and I tried setting it on everyone (13) – Emil Avramov Nov 8 '12 at 15:20
If you are going to do a home server, the absolute best thing you could do is hardwire it and set a static IP. That doesn't help with the router issue directly, but it will provide significantly better performance and less interference. – nerdwaller Nov 8 '12 at 15:22
I can't use a cable. I need to drill two walls for that. I understand it's the better option, but it's impossible for now. – Emil Avramov Nov 8 '12 at 18:10

Several reasons why the speed is limited to 68/72 Mbps.

  1. 150Mbps is the theoretical limit of wireless transfer. This includes all the data, several layers of network headers (TCP/UDP, IP, mac layer), control packets between the end points, packets lost due to collision (wireless is a shared medium), etc. The products are sold with the highest number possible even though practically it can never be achieved.

  2. The speeds can be affected by the signal strength. It can dynamically change the speed that is negotiated between the router and the laptop based on the signal strength (I think). Higher speeds might be possible if the laptop is brought closer to the router.

  3. Either the source or the destination could be a bottle neck. Not sure what was being transferred when you measured the speed, if you are transferring a huge file from the server to the client, the bottle neck could be file reading speeds in the server or the file writing speeds in the client. For eg. if the client cannot write fast enough it will flow control the traffic.

  4. USB adapter could reduce the speed of the transfer since it is another bus device which means it could be shared with other USB devices in the laptop and hence can affect the speed.

  5. Poor router quality. It might be routing or transmitting packets slow.

Somethings you can try.

a. Try connecting the laptop directly to the router using a cable and see what the performance is. That can eliminate point 3 as the cause if you can get faster speeds.

b. Try bringing the laptop next to the router to see if the speed increases. That can clarify if point 2 is playing a part.

c. Try a different router of better quality. Of course this will not give 150 Mbps but might improve. If you ask me for 150 Mbps router, 72 Mbps is pretty good.

d. Better yet, get a faster router (not just better quality, but that supports upto 300 Mbps). This is only if you want higher speeds.

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It should be said that the WIFI standard is a lie. You can't get the promised speeds outside a lab, even if the devices are very close together.I agree that 72 Mbps is pretty good for a 150Mbps router. – davidgo Sep 7 '13 at 21:03

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