SRXN3205 Slow file transfer over WLAN

40Mhz is full N using bonded channel so you would expect upto 300Mbps.

each wifi devices will device equally so in nature, speed will change between single wifi <-->wired transfer vs wifi <-->wifi.
3.3Mb/sec is only about 25Mbps

40Mhz is full N using bonded channel so you would expect upto 300Mbps. [...] 3.3Mb/sec is only about 25Mbps

That is the reason, why I wrote this question and can't understand why the speed is so low. I will test the single devices with a transfer on a wired computer and report the results.

So I tested it again and the maximal through put over WLAN is 7 MB/s and the device can transfer more than 7 MB/s.

Here are no other 5 GHz WLANs around and we are sitting next to the router.

seems only using 802.11A (54Mbps/5Ghz) speed

Yes, but Windows shows me in the device settings 300MBits.
What shall I trust?

Welcome to the world of wireless - where advertised speeds are the maximum theoretically available and NEVER attainable in the real world.

For reasons best known to the IEEE and the equipment manufacturers, the manufacturers are allowed to advertise the maximum theoretical speeds of the technology, rather than the actual throughput of the product - it has been this way from the time WiFi was accepted as a mainstream technology.

802.11b - advertised at 11mbs - is incapable of delivering more than 6~7 mbps
802.11a & g - advertised at 54 mbps - will not deliver more than 22~25 mbs
802.11n - advertised at 300 mbps - will not deliver more than 70~80 mbs.

I know you're going to tell me that your 25 mbs is far less than the 70~80 I'm saying is possible, but, you need to learn what it takes to deliver that 70~80 and see if the combination of router & adapter can meet it.

The 802.11n specification allows for four spatial streams - which would require both router & adapter to have four channels (four radios & four antennas) - the most I have seen are three, and that is relatively rare - the norm appears to be two - please note the word appears is in italics, that's a personal observation - right now I'm searching for a wireless access point that will support more than two streams and in both frequency bands - it might be easier to find the holy grail.

Thanks for the enourmous informations about wireless.

In general I can agree with all points, but it doesn't explain why a laptop can reach with other network more than 12 MB/s and not with the SRXN3205.
Is the WLAN throughput not high enough?

You don't mention this 12MB/s laptop in your other posts, nor do you provide any details as to the circumstances under which this 12MB/s throughput was achieved - I am therefore not in a position to make a comment.

Suffice to say 12MB/s, which translates to roughly 120mbs (yes I know it's 8 bits to a byte, there's also addressing & encryption overhead), is significantly faster than most wireless systems are capable of, and I'd certainly like to know ...

a) what wireless router/access point was used
b) what wireless client was used
c) how the throughput was measured.

It is a 5 GHz n-Network with 300 MBits with -38 dB. The access point is following Aruba AP-124/AP-125. Throughput was measured with a HTTP download.

I forgot informations about the used wireless device:
device: Intel Centrino Ultimate-N 6300 AGN
driver version: 13.4.0.9
driver date: 18.10.2010