Linksys WRT54gs v5
 

So...when we got the laptop awhile back, we also snagged a Linksys wireless router from Sams at the same time. Did I know that some were tremendously more desireable than others? I did not. But now that I have it in service, and have spent some time trying to improve its performance without spending money, I find that I should have checked it out first.

It seems that the WRT series of Linksys wireless G routers were made with 8 megs of flashable ROM and a *Linux operating system*. Why is this cool? Because the Open Source crowd has created hacked operating systems that let you do neat things with them...the neatest being that you can *increase the output power* of these things.

I need to increase the output power on mine, because I am getting terribly marginal signal in my kid's apartment across the driveway, and I can't spend $100 on a bridge or other nifty signal gizmo right now. However, beginning with v5 of these boxes, Linksys cut the ROM down to 2 megs and changed the OS to VxWorks, effectively making it no longer possible to hack these boxes and subvert them to your whims. Bastards.

There is an alleged method to install a stripped down version of one of the most popular of such firmwares, but despite having followed the instructions implicitly, I was unable to do it. So...any of you out there enough of a computer geek to give me any ideas, here?

To let you know how desparate I am, today, I took the little coax-connected remote antenna on my kid's 'net card and stuck it into a coffee can through a hole in the bottom at a calculated position, making a "cantenna".

It improved the s/n by 100%...

That's awesome! If the corporations won't provide what you need, you make it yourself.

Get this firmware then...
 

I had this router, and used this firmware with it:

http://www.dd-wrt.com/dd-wrtv2/index.php

This is an excellent router when you reflash it the right way :)

Mitch

Is there anyway you can tell what version it is from the box, barcode, whatever without opening it?

I did try the micro version of dd wrt, following some rather detailed instructions to the letter. The router refused the binary that you are supposed to load first.

There are several versions of this router, with the change coming at v 5.0. Mine is 5.0. You may have gotten an earlier version? At any rate, this is the link from whence my attempts ensued.

Also, as far as I have been able to tell, you cannot ascertain what version you are getting from looking at the box.

I had a v5
 

I bought my v5 for $40 on eBay :).

It took me two tries, but I did get it up and running.

Mitch

How does software increase power to a transmitter? WiFi outputs a full power and regulatory limited signal as defined by its unlicensed frequency band. How is this changed by software?

firmware
 

tw,

The firmware controls the transmit power of the radio via software.

You can adjust up to the max using the software.

Mitch

I'm all aquiver with excitement waiting for the followup to this one...let me just go get some popcorn.:corn:

Which is true with cell phones. But WiFi runs 100%. With any power reduction comes a data bandwidth reduction. Why would a WiFi port ever reduce power from 100% when that automatically means a reduction of signal to noise ratio and therefore a data bandwidth reduction below 54 Mb? I don't recall seeing any mention of transmitter power reduction or power control in 802.11 standards. Either it was on or it was off.

may be it reduces the packet size so insted of like 5 gallon buckets of data it is more like cups size packets , i know THAT can increse data flow ??

Just a thought , not an opinion .

I don't know jack about 802.11 standards and how they are acheived, but is it possible that the manufacturer designed the hardware to exceeding the 802.11 power standards? And to meet the standard, they could have used firmware to cripple the hardware's power and bring it down to the level of the standard? If so, then a change of the firmware could increase output to the level allowed by the hardware.

That's what I was thinking glatt. Is it possible that the output will exceed FCC limits?

If power is sufficent for a readable copy of the signal, data bandwidth remains constant, unless you tweak the modulation scheme...I'm not aware of any provision for that in 802.11.

For example, your Wi-Fi won't run faster if you shorten the hop distance from 20 feet to ten feet at constant RF power. And there's no advantage to running extra power unless the path loss has made the signal marginally readable...when adding power can reduce the number of unreadable packets, and this increases your range and/or aggregate data rate, as does changing the antenna gain to focus available power in a specific beam direction...that's what a Pringles can antenna does.

http://www.defcon.org/html/links/dc_...6592636783.jpg
Above: the "Sniper Yagi" demoed by the Schmoo Group at DefCon in 2004. Alleged to have 10 mile (15km) range.


Given the above, I'd guess that controllable power allows conforming the unit to regulations in various countries by changing the software config only.

I should add that S-band--the other name for 2.4 GHz--is not actually unlicenced...only the WiFi usage under FCC regs Part 15 is. Amateur Radio has a licenced primary allocation.

It should also be noted that more costly routers *do* have a higher output. I believe that the power level for home gear is some combination of "don't step on the neighbor's toes very much" and "hey, want better performance? buy this more expensive Professional Router!".

Also of note, if you use the dd-wrt firmware to 'turn up the power' (however that works), while you get increased range of signal (again, I'm not sure how it works, but it does, b/c I did it with mine at home), you also run the rotuer at a higher temp, which could (and does) break important bits.

Hello? You don't have a liquid intercooler on your router ???

Well duh, NOW I do...grumblegrumble...stupid bricked router....grumblegrumble

The Part 15 power limit (one watt) applies to all unlicened devices in this band, and there's no higher limit for "professional" devices. That said, I've read that most WiFi equipment runs between 20mw and 200mw. So check your spec sheets if looking to upgrade a device. I suspect a device using the lower end of that power range does so not out of courtesy but to use cheaper parts.

Of course, Part 15 prohibits you from using a non-type-certified antenna too.

You may find this calculator useful

So, in the continuing saga of trying to get broadband wireless to my kid at minimum cost, I purchased a used Microsoft MN500 802.11b wireless base station (router). According to what I am reading online, it is configurable as a bridge. I have followed the instructions describing this process, but so far, no joy.

Can anyone tell me this...When configured as a wireless bridge, shouldn't this device pick up my Linksys' signal and send it through a network cable to the desired computer?

Nope.

a bridge (wireless or otherwise) works only from a point to point location, and pre-supposes a permament connection. Bridges are useful mainly in the corporate networks, rather than in Internet connections. To be more succint, bridge conections cannot be routed. Re-configure your device as a router rather than a bride, and ensure your lan-side addresses are in the same range.
t

But it doesn't connect to the cable modem...so how does it get to connect to the Internet and our LAN?

Does it presume wireless? In other words does it need to pick up a wireless signal to forward? I have no idea about the device you got, that's just my initial thought.

Yes. That is the whole point, actually. To put the router, configured as a bridge, in a better location than the onboard computer card is in, and then have the router/bridge receive the wireless signal from the main house and transmit that via CAT5 cable to the network card on the remote computer.

Everything I read seems to indicate that this is a routine function for wireless routers, but damn if I can get it to work.

I beleve a "wireless bridge" doesn't use an Ethernet connection...it receieves and retransmits the packets that it hears, making it possible for a packet to travel further than a single radio hop would permit.

In ham radio we call that function "digipeating".

That would be mesh networking if it involved more than one wireless point. I believe mesh networking is coming in 802.11s. We are still waiting for 802.11n to be approved. I believe the 802.11s design will be based upon a Motorola technology which in turn was learned from designing military mesh networks.

Motorola equivalent on a metropolitian area network is called Canopy. Aspects of that same technology also may be implemented in WiMax or WiBro.

Meanwhile, using a wireless router as a communication repeater between two wireless computers has long been available. But I don't know if it works between 802.11b and 802.11g access points. It should.

Some routers do permit multiple wireless points to bridge to distant computers. But the routers must be from same manufacturer and I believe it is limited to only (maybe) four wireless points.

MIMO available in the Netgear RangeMax would have helped you. I've always found Linksys to be trash. The Linksys WAP I have doesn't even reach outside the living room. But the Netgear RangeMax reaches all over the house and the patio.

Nonetheless, for work, I was given a Linksys "wireless range expander" (repeater) to test. It has no wired ports and simply repeats the wireless network signal that you configure for it. I haven't tested it yet.

The Buffalo "air station" ethernet bridge recieves a wireless signal and provides connection to it via 4 ethernet wired ports. We've tested it and it works very well.

Sunday, I spent 6 hours working at our booth at a local Art & Wine festival explaining wireless connectivity to a bunch of luddites and drunks. It was so much fun I stayed longer than my 4 hour shift.

We use dual and tri -band radios that mesh via 802.11a and connect to customers via 802.11b. In some cases, we support municipal services thru 4.9 GHz licensed band.

Anyone familiar with dd-wrt know if I can link two routers with the same ssid and move between them seamlessly?
Specifically: one ssid, two seperate wired connections leading to the same external connection.

Yes. With Win/XP alone you can't see the different sources of SSIDs. Other software often report a more detailed list of SSIDs, including duplicates, and their MAC address sources and signal strength. This software is often packaged with hardware such as USB Wireless Adapters for PCs and multi-PC Wireless Access Points.

It's never completely seemless as it may take a few seconds for your connection to be handed off to a different source radio. That's why trains and bookmobiles have their own source radios to mesh with local fixed radios, rather than managing client connections that move.

Good idea! I've been using Wi-fi hopper, and that's a sweet package, but I'll try with the Windows Wireless Zero configuration.
+15 points to Rock Steady!

UPDATE:
Double Bonus Points for RS. That worked like a charm! I can now walk over 10,000 sq. ft. of warehouse/office/server room without having to disconnect and reconnect my wireless signal. Badassery!

Very good. Did I already tell you that my bro lives in Minny? Went there twice in the last 4 years.

You did not.
It's a good town. I spent most of last year in Ft. Lauderdale, and that made me appreciate how much I like the TC and MN in general.