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SSID Spec

PostPosted: Wed Aug 17, 2005 2:49 pm
by lullabud
I don't know that this is necessarily off-topic, but I couldn't create threads anywhere that seemed appropriate...

I'm can't seem to find conclusive information about the allowed characters for an SSID, or the allowed length thereof. From what I can tell, you're allowed to use any character, be it ascii or upper-ascii or whatever. The limit seems to be somewhere around 32 characters... Does anybody have a link to a definitive answer?


Oh, and hi to everybody who I haven't talked to in the last few years.

PostPosted: Wed Aug 17, 2005 2:59 pm
by wrzwaldo
The limit is 32. If I recall the spec says alphanumeric.

PostPosted: Wed Aug 17, 2005 3:07 pm
by lullabud
Yeah, I think 32 is the answer. That's actually part of the problem though. I don't know that it's 32. I know that alphanumeric is definitely not right though. Looking through a list of stumbled AP's shows other characters like spaces, underscores, hiphens, etc.. So, really what would be perfect is a link to a definitive answer. The Wi-Fi Alliance home page is pretty crappy and I can't find the spec there... go figure.

PostPosted: Wed Aug 17, 2005 3:12 pm
by King_Ice_Flash
lullabud wrote:Yeah, I think 32 is the answer. That's actually part of the problem though. I don't know that it's 32. I know that alphanumeric is definitely not right though. Looking through a list of stumbled AP's shows other characters like spaces, underscores, hiphens, etc.. So, really what would be perfect is a link to a definitive answer. The Wi-Fi Alliance home page is pretty crappy and I can't find the spec there... go figure.

I thought the answer to the life, universe, and everything was 42?

PostPosted: Wed Aug 17, 2005 3:18 pm
by renderman
It's 32 characters. It's buried in the 802.11b spec somewhere, I'm not going digging for you

Any ASCII charachter is legal, though anything really wierd tends not to be liked by alot of clients (who limit themselves to alphanumeric), and alot of AP's web interfaces only allow alphanumeric.

I've got a paper coming out soon about this stuff. When I get off my ass and write it, I've found some fun you can have with SSID's

PostPosted: Wed Aug 17, 2005 3:28 pm
by fregniacciaro
King_Ice_Flash wrote:I thought the answer to the life, universe, and everything was 42?


I checked it very thoroughly and that quite definitely is the answer. I think the problem, to be quite honest with you, is that you've never actually known what the question is.

PostPosted: Wed Aug 17, 2005 3:28 pm
by beakmyn
renderman wrote:It's 32 characters. It's buried in the 802.11b spec somewhere, I'm not going digging for you

Any ASCII charachter is legal, though anything really wierd tends not to be liked by alot of clients (who limit themselves to alphanumeric), and alot of AP's web interfaces only allow alphanumeric.

I've got a paper coming out soon about this stuff. When I get off my ass and write it, I've found some fun you can have with SSID's


Like using FakeAP to stream newsfeeds? and the tinyurl SSID?

PostPosted: Wed Aug 17, 2005 3:39 pm
by lullabud
OMG, 42... How could I be so STUPID? Man, I'm sorry for wasting everybody's time... *hides his face in shame*


After digging around I found the answer to my question at the IEEE 802 Standards site.

"The length of the SSID information field is between 0 and 32 octets." -- 802.11 spec, Ratified 1999, reaffirmed June 2003.

PostPosted: Wed Aug 17, 2005 4:09 pm
by lullabud
This is kind of interesting too... Kistmet limits SSID's to the range of ascii characters between ' ' and '~'. This would seem to indicate that SSID's only use those characters, but that only uses up about 1/3 of the possibilities that an octet offers. This is where I get curious about the interesting stuff that renderman was refering to. Hmmmmm......

PostPosted: Wed Aug 17, 2005 4:26 pm
by Dutch
lullabud wrote:This is kind of interesting too... Kistmet limits SSID's to the range of ascii characters between ' ' and '~'. This would seem to indicate that SSID's only use those characters, but that only uses up about 1/3 of the possibilities that an octet offers. This is where I get curious about the interesting stuff that renderman was refering to. Hmmmmm......

Kismet mungles the SSID before displaying it, in order to avoid Bad Things<tm>.
That doesn't mean you can't use other characters in a SSID. I.E. the Danish alphabet has special characters, which is located above ASCII 128. These characters are valid in the SSID. Kismet just don't display them.

Dutch

PostPosted: Wed Aug 17, 2005 4:39 pm
by wrzwaldo
lullabud wrote:Yeah, I think 32 is the answer. That's actually part of the problem though. I don't know that it's 32. I know that alphanumeric is definitely not right though. Looking through a list of stumbled AP's shows other characters like spaces, underscores, hiphens, etc.. So, really what would be perfect is a link to a definitive answer. The Wi-Fi Alliance home page is pretty crappy and I can't find the spec there... go figure.


Alphanumeric includes special characters and punctuation...

http://dictionary.reference.com/search?q=alphanumeric

And I just told you it was 32. :rolleyes:

PostPosted: Wed Aug 17, 2005 5:05 pm
by lullabud
wrzwaldo wrote:Alphanumeric includes special characters and punctuation...

http://dictionary.reference.com/search?q=alphanumeric

And I just told you it was 32. :rolleyes:


Wow, you're totally right. I would've figured that Alpha-Numeric would mean "Alphabetical characters and numerical characters", however, according to the Wikipedia definition of alphanumeric, it really does include punctuation. Kick ass, I'm switching my home SSID to use the interrobang as soon as I get home! Oh, and to confuse hackers who are trying to manually type my SSID, since they don't need no stinking point and click snazzy Graphical UI, I'm going to use the ellipsis to make them think it's really a dot dot dot. I'll be invincible!

PostPosted: Wed Aug 17, 2005 5:14 pm
by wrzwaldo
lullabud wrote:Wow, you're totally right. I would've figured that Alpha-Numeric would mean "Alphabetical characters and numerical characters", however, according to the Wikipedia definition of alphanumeric, it really does include punctuation. Kick ass, I'm switching my home SSID to use the interrobang as soon as I get home! Oh, and to confuse hackers who are trying to manually type my SSID, since they don't need no stinking point and click snazzy Graphical UI, I'm going to use the ellipsis to make them think it's really a dot dot dot. I'll be invincible!


Of course a good dose of common sense could be usefull. Wikipedia is as useless as tits on a boar hog! I guess if you wanted "a link to a definitive answer." you should have visited the ieee web site.

PostPosted: Wed Aug 17, 2005 6:18 pm
by G8tK33per
lullabud wrote:I don't know that this is necessarily off-topic, but I couldn't create threads anywhere that seemed appropriate...

I'm can't seem to find conclusive information about the allowed characters for an SSID, or the allowed length thereof. From what I can tell, you're allowed to use any character, be it ascii or upper-ascii or whatever. The limit seems to be somewhere around 32 characters... Does anybody have a link to a definitive answer?


Oh, and hi to everybody who I haven't talked to in the last few years.

Those damned FAQ's...

PostPosted: Wed Aug 17, 2005 6:33 pm
by theprez98
G8tK33per wrote:Those damned FAQ's...


What is a FAQ? Can you add that to the wireless dictionary? ;)