Does 802.11b use a lot of resources?

[Christopher Kelley]

Loren M. Lang wrote:

>On Wed, Mar 02, 2005 at 01:26:45AM -0500, Bob Johnson wrote:
>  
>
>>On Friday 25 February 2005 12:06 am, Christopher Kelley wrote:
>>    
>>
>>>Have I tried too hard to squeeze usability out of an old computer?
>>>
>>>I have a Pentium-166 that has been a faithful router & firewall (FreeBSD
>>>5.3 and pf) for a couple years now.  It has no trouble with the 3 to 4
>>>Mbps I get from my broadband connection, at least not with ethernet.
>>>
>>>I wanted wireless, so I could use my laptop around the house.  I
>>>dutifully read the section in the manual about setting up FreeBSD as an
>>>access point. I'm using a Netgear MA311 802.11b card (Prism 2.5
>>>chipset).  And it does work, except it's very slow.  Now I know that I
>>>can only expect about 50% of the rated speed with wireless, but I
>>>figured even if I got only 4Mbps, I'd be fine.  But I get less than
>>>1Mbps.  I've updated the firmware, added a signal booster and hi-gain
>>>antenna, and I have "excellent" signal strength throughout my house.
>>>
>>>So my question is, is there more overhead with wireless than with
>>>ethernet?  TOP doesn't seem to show that I'm taxing it too hard, idle
>>>never goes below about 70% with polling enabled (Hz=1000), and never
>>>below about 80% with polling disabled.  Am I expecting too much out of
>>>an old Pentium-166?
>>>
>>>      
>>>
>>My experience is that:
>>
>>1) 50% throughput is probably the best you should expect.  I generally plan on 
>>3-4 Mbps for an 11 Mbps 802.11b card.
>>
>>2) Using 128-bit encryption (WEP) will significantly slow down some (many?) 
>>cards. The WEP processing is done on the card (I think), and they simply 
>>don't have hefty processors. If you use 128-bit WEP, try 64-bit WEP and see 
>>if that speeds things up.  64 bit WEP is adequate to keep out casual 
>>snoopers, and 128 bit is not adequate to keep out a serious attacker, so the 
>>difference in security may not be as important as some believe.  64-bit WEP 
>>is also known as 40-bit, and similarly for 128-bit WEP.
>>    
>>
>
>Actually, what I recommend for home you, if you have the time, is IPSEC.
>Much more secure than WEP and it's all done on the main cpu so it should
>slow the wifi down as much.  There's a good article on freebsddiary.org
>I believe.
>
>  
>
I found the article on freebsddiary, and I admit I only skimmed it, but 
I have a mix of FreeBSD and Windows (XP) on my wireless network, and for 
now I'd like to keep it as simple as possible.

Christopher