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[on:]

Since no one seemed to have the arduino wifi shield in stock (in the US) we had to find an alternative that supported 802.11g.  We opted for the DFRobot shield since they claimed it supported 802.11b/g/n.  However our testing is showing that it is really a 'b' only shield since we cannot get it to see our a/g/n routers.  Any router that supports 802.11b it seems to see just fine.  I am a bit disappointing in the misleading advertising (or hopefully/possibly poor documentation).  If anyone out there can correct me on this, I would be very pleased.

I noticed today that the Arduino version seems to be in stock now.  So the other option would be to try and return what we have and get one of those.  It lists itself as supporting 802.11b/g .  Will this shield actually work on our 802.11g routers with no support for b?

UPDATE: I have done some further tests with the DFRobot shield and it seems to work with a linksys wireless router in 802.11g only mode so it does appear to work with some 802.11g routers.  The question now is why it won't see our enterprise grade routers (made by Xirrus).  My question about the Arduino version remains the same as I will probably switch to that shield for future projects.

[Reply #1 on:]

 Will this shield actually work on our 802.11g routers with no support for b?

I have never heard of such a thing. Every consumer and enterprise grade wireless router I have ever used supported the current newest format, and all the previous ones. Usually through a setting called "mixed mode". -Correction, "Mixed-Mode" is apparently a new term that deals with N devices, but the idea is the same. b/g/n are backwards compatible, and you can change this setting on the router.

Sounds like the router is misconfigured. It is common to disable b/g support on a router because it can slow the remaining faster devices down.

[Reply #2 on:]

These are enterprise grade routers and the b protocol is disabled intentionally.  The protocols do not have to be backwards compatible.  Most routers do support the mixed mode but leaving mixed mode on has downsides to performance when a b device actually connects (it often downgrades everyone else to b as well).  Mixed mode was around before n (my old SMC g router could be "b only", "g only" or "mixed").  Our network engineers have chosen to disable support for b.  

I guess my point is that if you say your device supports 802.11b/g/n that implies that it can run in all three of those modes. 802.11b/g/n itself is not a standard.  It represents three separate standards.  Marketing has shortened it by saying 802.11b/g/n when a device supports all three standards.

[Reply #3 on:]

I guess my point is that if you say your device supports 802.11b/g/n that implies that it can run in all three of those modes. 802.11b/g/n itself is not a standard.  It represents three separate standards.  Marketing has shortened it by saying 802.11b/g/n when a device supports all three standards.

According to the spec sheet for that module, it does support b/g/ and n.

http://www.wiznettechnology.com/Sub_Modules/en/product/Product_Detail.asp?cate1=&cate2=&cate3=&pid=1132

It also supports WEP and WPA/WPA2–PSK, so I don't know what to tell you.

[Reply #4 on:]

It was that statement which caused us to buy it.  However looking at it now, I can see clues that supports what I am seeing.

This one for example:

Operates with standard 802.11b/g/n access point at speed up to11Mbps (802.11b)

The page you reference also claims the "Radio Protocol" is "802.11b/g/n compatible".  What exactly is "Radio Protocol"?  802.11x is a specification, not a protocol.  Are they saying that since b, g and n all can operate at 2.4 GHz that their b device has the same "radio protocol".  They might as well say their device's Radio Protocol was compatible with "802.11b/g/n/bluetooth" devices.  Bluetooth also operates ant 2.4 GHz but the wiznet device can't connect to a bluetooth device anymore than it can connect to a 802.11g or 802.11n device.  Their documentation is confusing at best and intentionally misleading at worst.

[Reply #5 on:]

So I think we are getting sidetracked a little from my main question.  Has anyone tested the Arduino WiFi shield with 802.11g only routers (without mixed-mode or 802.11b compatibility enabled)?

[Reply #6 on:]

Just to close this thread I figured I should say that I did end up getting the Arduino WiFi shield.  Within 5 minutes I had the thing installed, talking to our enterprise access point and hosting a web server.  The difference in experience between these these two shields was night and day.