[lug] Wireless pcmcia for linux

[Nate Duehr]

On Wed, Nov 15, 2000 at 01:24:35PM -0700, Kevin Fenzi wrote:
> To: herold at cslr.Colorado.EDU (HEROLD)
> --text follows this line--
> >>>>> "HEROLD" == HEROLD  <herold at cslr.Colorado.EDU> writes:
> 
> HEROLD> Can anyone recommend a wireless pcmcia network card that will
> HEROLD> run in linux and that other OS?
> 
> I would reccomend the 11mb 802.11b cards from lucent...

Ditto.  

> The "silver" ones are about 160$. The "gold" ones are more and likely
> not worth it. (That determines how much hardware encryption it
> does...) From what I understand if you enable full encryption with the
> gold cards your throughput goes all to hell. ;( 

I've never seen this, I have a Gold card and run it with a 40-bit
encryption key at home off of an Apple Airport for the base station, and
128-bit at the office off of standard Lucent (now Orinoco) Access
Points.  I'll try to do some real testing and get back to the list, but
I can't say I've ever seen it in practice.  My card is a true Lucent
(not Orinoco) with Firmware Rev. 1.01 using the wvlan_cs GPL'ed driver,
not the Lucent wavelan driver.

> You need to make sure and get cards that are "802.11b" not just
> "802.11". The "b" makes them 11mb cards and much more standard. The
> plain 802.11 cards can only do 2mb. Also, the lucent cards are nice
> because they have a plug for an external antenna. Some 802.11b cards
> don't have any means for an external antenna... ;( 

Other comments about the experience I've had:

- If you don't need an external antenna on the wireless access point 
  and you want a real base station  -- if you have a Mac to manage it with,
  the Apple Airport is pretty nice and looks good sitting on a desk.  It
  will only do 40-bin encryption, however.  ("Silver" in the Lucent
  terminology.)  You do have to own a mac to manage it though.  
  
- Others like Lynksys have just come out with AP's as cheap as the Airport,
  and who knows what their service reliability will be.  Lucent wants an
  arm, a leg, and a newborn child for their AP's, but rumor has it that
  they're going to release a 40-bit encryption only version of their AP
  in a cheaper case with an on-board no antenna xmtr/recvr for around
  $400.  

- If you don't mind fiddling around, you can take one of these cards and
  put it in a PCI or ISA adapter board and get one of your linux
  machines acting as an Access Point instead of buying a real one.  I
  didn't have enough time on my hands to futz with this, but it would
  have saved me about $100.

- Cisco does really strange things with their SSID's (I believe you
  enter them in Hex or something similar) so if you're going to mix
  vendors, be aware.

- Cisco's software for their cards doesn't support multiple profiles for
  different locations.  You end up having to type in different
  encryption keys over and over again to move from site to site.
  Lucent/Orinoco's software supports four locations and up to four
  network keys (if your policy is to rotate them, for example).

- Turn on the encryption!  Even if it's only 40-bit!  Setting your NWID
  to nothing makes your wireless card promiscuous.  You can see and
  sometimes attach to networks you don't own.  (You have to deduce the
  ESSID, but my understanding is that with the NWID disabled, you can
  sniff it.  Remember no matter how secure you think it is, even with
  encryption, it's still wireless.  Get and use 128-bit encryption if
  you're going to use it in a corporate setting.  (Comments about
  throughput still outstanding...)

- Only one other thing: The Apple Airport in bridging mode didn't play
  nicely with broadcast packets from my Debian Linux (potato) DHCP
  server.  Never did figure out why... just turned off the DHCP server
  in the Linux box and turned on NAT/DHCP for wireless clients in the
  Airport.  Works great.

In general, um... I'll never go back to wired networking (except between
servers and CD-ROM ISO transfers on 100Mb) again.  Wireless is great for
the vast majority of what I'm doing, and doubly so because I work so
much on laptop(s) now.

(I also have an iMac DV SE in the living room -- look ma, no wires!)


-- 
Nate Duehr <nate at natetech.com>

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