Converting from "b" to "g"

[Ed Hansberry]

I want to convert my 802.11b WLAN at home to 802.11g. The addition of a Windows XP Media Center to the family and moving around video files is just too painful over "b" speeds.

I currently have a Linksys BEFW11S4 that I am 100% happy with so am inclined to go Linksys again, probably the WRT54G.

I know I'll need to get a new USB "g" adapter for the MCE so it can talk at those higher speeds and will also get a new PCMCIA card for my notebook. I have no desire to talk at those speeds though with my Pocket PC. Will there be any issues, other than the temporary drop in LAN speeds when online, with just using my Socket CF WiFi card? Anyone else using this card with the WRT54G router?

[Janak Parekh]

I believe temporary speed drops is it. You'll have to leave the WRT54G in "mixed" mode. I haven't done any benchmarks, though.

However, just a note of warning with the WRT54G: I found it has substantially worse range than the BEFW11S4. I had a BEFW11S4 at a client that got fried during the ROM upgrade and replaced it with a WRT54G, only to find it had about half the range, so I had to downgrade them back to another BEFW11S4. I hope the unit I worked with was defective, but I don't think so. :| And this was with the ROM at the latest version, and using different radio channels. If you're at 4/5 bars at the farthest with the BEFW11S4, you should be OK, but beware if you're at 2-3 bars.

--janak

[arnage2]

b+g mode will lower speed.

[c38b2]

Will a b-g transaction slow down a simultaneuos g-g more than another g-g transaction at the same settings? :?

[Janak Parekh]

Will a b-g transaction slow down a simultaneuos g-g more than another g-g transaction at the same settings? :?
Definitely. A "b" connection slows down every other connection to/from the router at that same time.

--janak

[c38b2]

Definitely. A "b" connection slows down every other connection to/from the router at that same time.
8O OK, I guess the next question is how much? With a 'b' user on the network do all the 'g' users have reduced bandwidth to that of 'b' networks?

Oh, and does this affect wired networks? Do 100Mbps users feel the pinch if a 10Mbps user logs on?

[Janak Parekh]

8O OK, I guess the next question is how much? With a 'b' user on the network do all the 'g' users have reduced bandwidth to that of 'b' networks?
I think the presence of a b node slows down all g users on that base station to something like 15-20mbps tops. This is why I'm not very bullish on g at all. I'll be deploying 802.11a in a few places, because it's not susceptible to this problem and because the 5GHz frequency band is less polluted -- but will only do so in business environments, because a is more expensive and has even less range than g. :|

Oh, and does this affect wired networks? Do 100Mbps users feel the pinch if a 10Mbps user logs on?
No. Separate subnets. Unless you've got a wireless server. ;)

A workaround, mind you, would be to deploy two wireless networks in your house, and hook them together via a hub or switch -- a "g-only" network, and a "mixed" or "b-only" network. This is a bit of work, though, and isn't for the network newbie. :)

--janak

[Ed Hansberry]

8O OK, I guess the next question is how much? With a 'b' user on the network do all the 'g' users have reduced bandwidth to that of 'b' networks?
I think the presence of a b node slows down all g users on that base station to something like 15-20mbps tops.
Is it the presence of a b node or is it a b node actually on and using the network.

What I am getting at is if I have all of my security stuff done and not allowing anyone on my LAN without a security key, will my neighbors b client just being around cause me to drop to these slow speeds?

[shawnc]

Ed,

You guys might as well be speaking Greek to me, but I'll share with you my experience.

I have a Lynksys G router and pc card for my laptop that I purchased this past summer. In January, I introduced my 4150 into the mix. Obviously my 4150 surf's at a slower speed, but I have not noticed ANY difference in speeds on either the laptop or our desktop.

[JustMe]

Keep the Ipaq on the B router and upgrade everything else to the G hardware.

That is what I did and everything is running full speed.

JM

[Janak Parekh]

I have a Lynksys G router and pc card for my laptop that I purchased this past summer. In January, I introduced my 4150 into the mix. Obviously my 4150 surf's at a slower speed, but I have not noticed ANY difference in speeds on either the laptop or our desktop.
Of course, it depends on whether or not you were "maxing out" the 802.11g connection. :)

Is it the presence of a b node or is it a b node actually on and using the network.
I think it has to be physically turned on, but I haven't done the testing. You might want to try a few searches for "802.11g mixed mode" for more discussion.

--janak

[Mark_Venture]

Suggested reading on the subject of B vs G speeds, both in B only, Mixed mode, and G only....

http://www.dslreports.com/forum/remark,8026298~mode=flat
http://www.dslreports.com/forum/remark,7393295~root=wlan~mode=flat
http://www.dslreports.com/forum/remark,7835833~root=equip,16~mode=flat
(they also include other links and tests/results, including PCMagazine write ups)...

To sum up and repeat what I posted back in September...

My Devices... IBM Thinkpad T23 with Linksys WPC54G (802.11G) card, iPAQ 2215 with Ambicom WF1100C-CF (802.11b) and a Linksys WRT54G wireless router (802.11G) stacked to Linksys BEFSR41 with PC's wired to it.

With just the laptop (WiFi card removed from iPAQ), I get sustained transfer rates of 20 to 22Mbps. When I turn the iPAQ on with the WiFi card inserted and surf the net in addition to the laptop, The laptop's transfer rate drops to around 16Mbps.

The only way for me to test B only speeds is to put the Ambicom card in the Thinkpad with a Compact Flash to PCMCIA adapter. Doing that, B is about 5 to 6Mbps.

So when use both B & G devices at the same time, the speed of the G clients, drops, but not all the way down to B speeds.

Oh, and I should say, that the Wireless icon in the system tray of WinXP on the laptop always reads 54Mbps Excellent signal strength.

(speeds measured via AnalogX NetStat Live while copying file from laptop using WiFi to a desktop wired to the WRT54G)
Also, test were done with the router set in MIXED MODE at ALL TIMES. I did not test with the router set to G-ONLY mode.

[Janak Parekh]

Thanks for the numbers, Mark :) Still sounds like a bit of a performance boost -- I'm curious about the range, though, compared to b-only routers...

--janak

[that_kid]

I can't speak for the benchmarks but I've transfered files from my file servers to my laptop with my wap54g and wrt54g with just the "g" cards gives and I found that I get the same throughput as when transfering files in mixed mode with my ipaq's connected and accessing the network as well. I've read through all the things saying that the speeds will decrease but I'm going by what I've done myself. As always ymmv but so far I have no problems running mixed mode and getting 2 MB/s transfers to the "g" cards....oh and yes that's 2 megabytes per seconds 8O. Having said all that I run my "G" cards on an ap to themselves to take avantage of wpa and I also have my other ap's behind another firewall.

[Mark_Venture]

...I'm curious about the range, though, compared to b-only routers... That I can't comment on... I had a BEFW11S4 for only about 3 days... It was too slow for streaming audio/video to the laptop so I took it back and got the WRT54G.

My apartment is 998sqr feet. I'm in the bottom floor at the end of the building. The WRT54G is almost in the middle of front to back, but on the "inside" wall (i.e. closer to my neighbor than the end of the building.) I can go anywhere in my apartment with the laptop at get 100% signal strength (according to the Linksys utility for the WPC54G card). With the iPAQ, PocketWiNc always shows full signal.

I have not gone outside with the laptop, but with the iPAQ, I can only go about 200 feet out front before I loose connection. This might be due to the fact that the ground slopes from front to back of the apartment along the outside wall. The front of my apartment is about 4.5 feet below ground, the back is at ground level (I can walk out my sliding glass door and keep on going.) The router is about 2feet off the floor in the room its in. The ground around the walls might be cutting down the signal outside. I can't walk too far behind my place... 10 feet out the back door I hit a tree line that dropps off about 30 feet nearly straight down to a creek.

[that_kid]

The range of the wrt54g is less than the BEFW11S4. I also have a BEFW11S4 here I used to use at my parents house and it put out close to 100mw which was great and had excellent coverage all over the house. With the WRT54G the coverage was less because linksys scaled the power down to 22mw, BUT because the WRT54G runs linux there are people who have come up with some nice firmware where you can adjust power up to 84mw, adds pptp server and client, bandwidth shaping, telnet to the box, vlans, the ability to assign certain dhcp ips to either the wlan or wired clients and some other things. Sveasoft (http://sveasoft.com/forum6.html) is one of the people who have been making great firmware for the WRT54G. When I replaced the BEFW11S4 at my parents house I bumped the power up to about 44 mw which gave a nice increase in coverage and stability.