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Wireless Woes - Lack of speed

 
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nordle
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PostPosted: Fri Sep 14, 2012 6:51 pm    Post subject: Wireless Woes - Lack of speed Reply with quote

Hello.

Do you remember a simpler world? A world where if we wanted things to communicate, we strung up a wire. Whether as a child, string and tin cans, or extending your telephone, installing a TV aerial. Indeed, the Victorians conquered much of the world by laying wires in straight lines. Our recent history is largely built on taking something from point A and controlling its exact path to point B. It goes where we tell it to. Wires. Controlled and orderly. The British way.

Fast forward to 2012 and we have this abomination that is wireless. It goes wherever it wants (usually not very far) and we have to stick things in places where we hope the signal will connect. We are no longer in control, instead dictated to by an invisible bunch of acronyms. The master is now the slave.

This is of course a very long winded and not very helpful post to essentially ask for advice / help. Which also means this is probably miss-post in terms of forum.

I have a dual band Netgear 802.11ac wireless router. Fifteen feet away, in line of sight and at the same height, I have a dual band Netgear 802.11n wireless extender. Attached to the extenders 10/100 ethernet ports using 2-3m CAT6 UTP are a PC (mythtv), TV and BluRay player.
Upstairs, a mere 4 meters from the router downstairs, is my desktop PC using a PCIE-1 Asus dual band 802.11n wireless NIC.

The router and extender are connected on 5GHz at 270Mbps.
The NIC and router are connected on 5GHz at 160Mbps.

With my old setup, the PC went to a router as did the mythtv box, on CAT5e UTP via 10/100 ethernet. Copying files via Samba share achieved 9 meg a second, or roughly 72Mbps.
Pinging the router was around 1-3ms

So now, I'm getting 160Mbps and router pings of 0.7-1.2ms
Not too bad considering I didn't have to drill through forests of floor boards and skirting.

So I should be getting a transfer of around 15+ meg a second, right???

Well, it's 4. Yes, I'm getting 4 meg a second. What the hell is going on? I've updated all the firmware. I've tried connecting the desktop PC at 2.5GHz and 5GHz, at 2.5GHz the speed drops to 3 meg/second

I've tried connecting to either the router or the extender. I tried running the extender in "Fast Lane" where it connects at 2GHz to outside devices and 5GHz to the router. Tried turning off my mobile, microwave and cordless phone.

The best I achieved was 5.5 meg a second. The theoretical speed of this is 37 meg a second.

Have I cocked up by buying an extender? If I connect the PC to the extender to send a file to MythTV (which is attached to the extender), does the extender send it to the router first, to then pass it back to the extender. I don't know enough and assumed that if connected to the extender, the data would not travel via the router. Even if it did, its still very poor throughput considering the connected speed.

I got annoyed and wiggled the aerial at the back of the desktop PC about 1 inch. I'm now connected stably at 215Mbps (from 160Mbps) and I'm getting....... 3.5 meg a second... ggrrrrrrr.
Where are the other 15-20 meg/sec?

Evil or Very Mad

PS. I'm pleased that the Asus pce-n53 works with Linux, albeit having to compile drivers they supply, but it was simple.
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wyliecoyoteuk
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PostPosted: Fri Sep 14, 2012 8:35 pm    Post subject: Reply with quote

What people often don't realise is that wifi bandwidth is shared.
It isn't this simple, but if you have 5 wifi devices accessing a wifi router, divide the bandwidth by 5.
If you use a repeater, yes it connects to the router, and traffic effectively travels via one port on the routers switch, which is shared with any other wifi device connecting to the router
A lot of routers effectively treat the wifi as one port, so if you have 5 ports each dedicated to one device, and five devices effectively using one port, guess which has the best throughput?

Again, It isn't this simple but really Wifi is excellent for surfing and email not bad for media streaming, rubbish for file transfers.
Another factor is device speed. one b or g device on the wifi can effectively reduce the speed of all other devices, even if they are n devices.

http://networking.nitecruzr.net/2006/05/you-have-to-share-wifi-bandwidth.html

Reading your post, your Myth box, TV, Bluray player and PC are all using the same port as far as the router is concerned.


If you are using a repeater, if you can connect it via ethernet cable that will almost double your wifi bandwidth.
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Bruno
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PostPosted: Fri Sep 14, 2012 9:02 pm    Post subject: Reply with quote

wyliecoyoteuk wrote:
...Again, It isn't this simple but really Wifi is excellent for surfing and email not bad for media streaming, rubbish for file transfers...


That's good to know, as I have observed the same (especially wrt file transfers) and just thought it was my kit.
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nordle
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PostPosted: Mon Sep 17, 2012 10:59 pm    Post subject: Reply with quote

This extender has the option to use one band for the incoming and one band for the outgoing, Netgear call it "Fast Lane".

So the PC connects to the extender via 5GHz, the extender connects to the router via 2GHz. So the latency through sending and receiving is reduced, albeit you then limit yourself to 145MBps.
But given the router and extender are less than 20ft apart, in line of sight in the same room, I figured that I'd get 95% of 145MBps. But no. That would be 18 meg a second, and I'm struggling to get over 6.

Probably should have spent the extra time on drilling and laying cat6 cable around the house before the carpet went down. But honestly, I stupidly thought 300MBps would beat 100MBps. Thought I'd be too old and cynical to fall for the marketing. But nope Smile
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wyliecoyoteuk
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PostPosted: Tue Sep 18, 2012 8:15 am    Post subject: Reply with quote

It is still half duplex, and all devices connected to the extender are sharing the bandwidth.
So the data from your mythtv box goes to extender, to the router and then to your PC.

Might be worth taking a mobile phone, if you have one with wifi, and mapping the signal.
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nordle
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PostPosted: Tue Sep 18, 2012 11:08 pm    Post subject: Reply with quote

wyliecoyoteuk wrote:

Might be worth taking a mobile phone, if you have one with wifi, and mapping the signal.


I've got an Android phone with WiFi. What does it mean to map the signal?
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towy71
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PostPosted: Wed Sep 19, 2012 1:11 pm    Post subject: Reply with quote

I believe there is and app that lets you wander about and work out where you lose signal

I'm sure someone will know of such Wink
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Ram
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PostPosted: Wed Sep 19, 2012 2:39 pm    Post subject: Reply with quote

Try Wifi Analyzer
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wyliecoyoteuk
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PostPosted: Wed Sep 19, 2012 2:54 pm    Post subject: Reply with quote

WiEye works well.
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towy71
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PostPosted: Wed Sep 19, 2012 4:18 pm    Post subject: Reply with quote

wyliecoyoteuk wrote:
WiEye works well.

is that a Geordie app? Laughing Laughing
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wyliecoyoteuk
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PostPosted: Wed Sep 19, 2012 5:04 pm    Post subject: Reply with quote

towy71 wrote:
wyliecoyoteuk wrote:
WiEye works well.

is that a Geordie app? Laughing Laughing


Groan. Methinks we need a bit of eckythump!
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