nanog mailing list archives

RE: Marriott wifi blocking


From: "Naslund, Steve" <SNaslund () medline com>
Date: Thu, 9 Oct 2014 19:41:31 +0000

I don't read it that way at all.  It is illegal to intentionally interfere (meaning intending to prevent others from 
effectively using the resource) with any licensed or unlicensed frequency.  That is long standing law.  

It says in (b) that you must accept interference caused by operation of an AUTHORIZED station or intentional or 
unintentional radiator (like a microwave oven which serves a purpose, or a amateur radio operator messing up your TV 
once in awhile (as long as he is operating within his license), not a jammer that has no purpose other than to prevent 
others from using an authorized spectrum).  To me that looks like as long as the other guy is using the frequency band 
in an authorized manner (i.e. not purposely stopping others from using it, but using it for their own authorized 
purpose) you have to deal with it.  So another guy using your channel (which is not really "yours") for his network 
would be fine but if he is purposely camped on your SSID and deauthing your clients is not using it legally.

As far as who owns an SSID, I don't think there is any law on that unless it is a trademarked name but the FCC rules in 
general give the incumbent user the right of way.  If two licensed systems interfere with each other (common in 
licensed microwave), the older system usually gets to stay and the new system has to change.  I think they would be 
unlikely to get involved in the whole SSID dispute (because they don't regulate SSIDs or the 802.11 standards) they 
would most likely tell you it's a civil matter and walk away.  Now, if you are using someone else's SSID for the 
purpose of intruding, you are violating Part 15 because that is not authorized spectrum usage.  That they will probably 
address.

I don't think the FCC would classify a wifi router operating normally as interference, but a device purposely bouncing 
clients off of the clients own network would be.  I have worked with them a lot as a frequency coordinator with the Air 
Force and find that the enforcement guys have quite a bit of common sense and apply a good measure of it to deciding 
what to enforce or not enforce.  My guess (you would have to ask them) is that an entity defending their SSID from 
unauthorized access is an acceptable security feature but someone using a different SSID and not trying to connect to 
the entities network should not be active messed with.  If my SSID is there first and you show up and try to kick my 
clients off so you can use it, you will appear to be the aggressor and I will appear to be the defender.  In the same 
way that it is not legal for me to punch you in the face unless of course you punched me in the face first and I'm 
defending myself.

It gets messy when you get into the cellular world.  I don't think you would be within the law jamming or blocking cell 
phones even within your building (even though the government is known to do so).  You could however have a policy that 
prevents people from bringing a cell phone into your building.  The public has no right of access to your property so 
you are free to make rules about what can and can't come within your building.  I do know that the areas I have worked 
in that had cellular jammers for security purposes are already areas where they are prohibited by regulation.  National 
security trumps a lot of other laws.

Remember, a lot of law is about intent and it is clear that the intent of this law is to allow everyone access to use 
the ISM spectrum for useful purposes and to prevent people from interfering with your right to do so.  Any case has to 
take that into account.  In the Marriott case, I think it would be a tough argument for them to show anything other 
than stopping people from using anything other than their wifi service when it is clear that someone could use their 
own network services without causing undue harm to Marriott.

In my own environment, there are tons of clients running around with their devices wifi tethered to phones and 
searching for their home wifi networks.  As long as they stay off my SSIDs, they will not be harmed.  If they try to 
connect to my SSID they better authenticate or they get denied.  If they keep trying, they will get ACL'd out.  If you 
set up an AP and try to plug it into my wired infrastructure that's when the active stuff comes into effect because you 
have no right to add a device to my wired network.

Steve Naslund
Chicago IL

-----Original Message-----
From: NANOG [mailto:nanog-bounces () nanog org] On Behalf Of Robert Webb
Sent: Thursday, October 09, 2014 2:05 PM
To: Owen DeLong; Brett Frankenberger
Cc: nanog () nanog org; Brandon Ross
Subject: Re: Marriott wifi blocking

So is the main factor here in all the FCC verbage become that the WiFi spectrum is NOT a licensed band and therefore 
does not fall under the interference regulations unless they are interfering with a licensed band?

I think the first sentence below says a lot to that.

The basic premise of all Part 15 unlicensed operation is that unlicensed devices cannot cause interference to licensed 
operations nor are they protected from any interference received.  The operational parameters for unlicensed 
operation are set forth in Section 15.5 of the rules, as follows:
(a)  Persons operating intentional or unintentional radiators shall not be deemed to have any vested or recognizable 
right to continued use of any given frequency by virtue of prior registration or certification of equipment,
(b)  Operation of an intentional, unintentional, or incidental radiator is subject to the conditions that no harmful 
interference is caused and that interference must be accepted that may be caused by the operation of an authorized 
radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) 
equipment, or by an incidental radiator.
(c)  The operator of a radio frequency device shall be required to cease operating the device upon notification by a 
Commission representative that the device is causing harmful interference. 
Operation shall not resume until the condition causing the harmful interference has been corrected.



Current thread: