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Inverting Images for Uninvited Users
Several readers offered comments on the methods of network interference suggested in the examples linked from the story, or offered other creative ways to impede network freeloaders. First, reader blantonl offers some insight into implementing the same image-flipping technique:
For those that are struggling to understand how the author of this article is accomplishing his approach, here is some further information.
The author obviously has a Linux server in his house, that is running DHCPD
To selectively send some clients to some locations, and others to the normal internet, he assigns an IP address on a different network to clients that don't have MAC Addresses that he knows about.
Forwarding on to sites of his choice is done by using IPTables, which is a utility that allows you to configure the packet filtering components of the Linux TCP/IP Stack. In this instance, the Linux box is just functioning as a firewall, and he is selectively sending requests from certain IP addresses to different hosts of his choosing.
Finally, the Up-side-down and blurry-image conversions is accomplished by sending page requests from those before-mentioned IP addresses to a proxy server, which in this case is Squid — and then allowing the proxy server to run a script which calls an ImageMagick command called mogrify which allows you to resize an image, blur, crop, despeckle, dither, draw on, flip, join, re-sample, and much more.
(Writing "I'm paranoid - I work in information security," reader hab136 points out some potential vulnerabilities in the system as described.)
As to the actual methods of annoyance, jpellino writes
Upside down is cute, but blurry is just too fantastic. You know they were on the horn to the vendor after punching every monitor control and several loud screaming matches and an expensive service call for a monitor that then worked just fine on the bench... As a webmaster I can now say April 1 just got very far away...
Reader Sloppy also admires the "blurry-net" approach ("That's subtle and I love it"), but suggests that image manipulation is only for starters
And perhaps the ultimate in annoyance-as-warning, reader Midnight Thunder writesThe next step is to spy on them and see what websites they visit, and then insert some fake content one day. For example, if they use it to read CNN, insert a casual story about a nuclear weapon getting used in the Middle-East or South Asia, or a story about the president of USA selecting a new vice-president due to the assassination last week ("What?! I didn't hear about that!"), or the CDC in Atlanta is investigating the recent rash of improbable claims about the dead returning to life to feast on the flesh of the living, etc. If they visit Slashdot, then the jig is probably up, but maybe it would be great to have a story where a security study found Windows98 to kick OpenBSD's ass and then a bunch of comments where everyone agrees that the findings pretty much match their own experience, along with complains about "how is this news for nerds?!"
Not all uninvited users are actually unwanted users, though, at least for some readers. Reader Elektroschock writesI suppose you could also add a frame to every page and then sell advertising space. Since you probably know a bit about your neighbour it is much easier make targeted advertising. Of course you could always make the top frame read:
"This is borrowed bandwidth. Have you thought about getting your own connection."
Oh and make sure it is flashing. Actually you could make it so that the whole content flash.
Similarly, trewornan writesSorry, I am a supporter of open networks. I think the freifunk olsr-protocol approach of open wireless networks is best. We don't need internet providers and we don't need internet providers which leak our communication data to the governments and endanger the freedom of the net. The net should be a net and wireless technology is great for the creation of a real P2P internet.
I cannot support any action against people who use your network. It is against my understanding of hacker ethics. When you don't like it then close your network. But no childish games please.
I may even say that I find it unethical to exclude your neighbours from using your network but I respect your opinions. When your network is open it means: Be free to use it. Not: You can use it but I will fuck up or intercept your communication.
I chose to leave my wireless network open so that if someone nearby needed a connection it would be available for them. If someone was to impose an unreasonable load on the network I might do something about it but so far (12 months) I've had about half a dozen people connect and download relatively small amounts of data - my guess is they were checking email. Why would I object to that? No . . . why would *you* object to that? The way I see it it's a chance to do something nice for other people, why not get yourself some good karma.
Even without that sort of altruism, many readers feel that, as geekoid puts it,
Not so fast, goes an argument exemplified in another comment from R2.0:[By]leaving it open he is inviting other people to connect.
Some computer says to the router "Hey, can I come in?" and the router says "Sure." Now, the moment you put something up, like needing a password, then you are no longer inviting people in.
- Computer says "Hey, can I come in" router says "Sure, if you know the password."
- Or you can encrypt it; Computer says "Hey, can I come in?" the router says "KE*jd7638JDEJE*834899(&^&#nd&#&bd*e#"
Yes, the computer is "asking" the router "permission," and the router is "granting permission" — the only problem is, the words we use to describe these actions may appear to be descriptive of thinking and volition, but they really mean neither. Computers and routers simply CANNOT give "permission" in any legal or moral sense.
To use the yard analogy that seems to be popular for these threads, lets supposed your neighbor's massively retarded child asks your massively retarded child for permission for his Daddy to use your yard, and your child agrees. Neighbor then comes over and stages a cookout on your lawn, or for that matter just walks across it.
When you confront him, he says "But my kid asked your kid, and he said yes." This is binding? Common sense and the law would say no, yet you would allow devices with an order of magnitude less analytical power than a retarded child to give and receive similar permissions.
Repeat after me folks: devices cannot give and receive permission for human actions without those permissions expressly being granted via some other means.
A traffic light doesn't give you permission to cross the street; the government (that you studied to get your license) gives you permission to cross the intersection when a light is green, and denies it when red.
Your ID badge doesn't ask permission to enter your building, and the security system doesn't grant permission; YOU ask for permission by presenting the badge, and your employer grants it by programming said system to accept your request.
Closer to the typical small-time network admin, perhaps, bennomatic writes
Various forms of the same disagreement surfaced in various corners of the discussion: squiggleslash, for instance, writesIf I leave my bike outside unlocked for 10 minutes, am I giving explicit permission to anyone who sees it that they can take it? No. Am I allowing it to happen through negligence? Sure, but call it what it is; it's still stealing, or at least trespassing.
Even something as amorphous as bandwidth is a limited resource. To paraphrase the head of the commerce committee, an open wireless connection is not a dump truck you can just load up with as much as you like; it's a tube!
The figurative "visibility" of an open wireless network also isn't enough to convince reader R2.0 that it's fair game for passers by. He writes:[I]t makes sense that no implied permission is given by simply having your router be unsecured, given "unsecured" is the default configuration of most off-the-shelf routers.)
It really isn't an issue in practice. If you want to use someone else's network, all you have to do is ask them. With 802.11, you're close enough to be able to do so. There's no reason not to ask, other than knowing that "No" is likely to be the answer. And I think that's why people tell themselves the myth that somehow they have implied permission simply because the "door" was left unlocked.
So the router is "visible," with an option to make it invisible. Big deal. My garden is visible from the street, but I can put a tarp around it to obscure its existence. What you are saying is that, unless I put a tarp up around my garden, everyone has a right to use it.
Wireless networks may make themselves conspicuous, but that does not confer an invitation to use them. The connection between "visible" and "inviting" is not legally or morally valid. (I am excepting the concept of "attractive nuisance," but I don't think open routers will come under that area of liability)
Reader 4e617474 fired the next volley in this battle of analogies:
No, actually we're saying that if your garden pelts us with carrots and peas as we walk past on the public street, we're at liberty to catch them and consume them. Only if you place anti-vegetable-flight netting around your garden (or stop planting vegetables that lend themselves to comparison to an unsecured WAP) does it become incumbent upon us to behave as good citizens.
Hey! Analogies are fun! Somebody compare Internet privacy law to hunting and fishing licenses!
Readers like ShawnDoc make a case persuasive for discouraging bandwidth borrowing on the basis of enlightened self-interest.
If someone uses your connection for illegal activity (downloading Meet the Fockers, kiddie porn) it will be your IP address that the RIAA/MPAA/FBI will trace. Good luck convincing them it wasn't you. You might be able to do it, but it will take up time and money (lawyers) to clear your name. And in the case of kiddie porn or other criminal act, expect every computer, PDA, and cell phone in your home to be confiscated to be analyzed for incriminating data. The second problem is you are allowing strangers access to not only your Internet connection, but also your LAN. I have multiple computers and put files in shared folders so I can access them from different machines. I don't want some strange to have access to those files, or worse, have their computer be infected with a worm/virus that propagates across the network.
Thanks to all the readers whose comments informed this conversation, and in particular to those whose comments are quoted above.
To use the yard analogy that seems to be popular for these threads, lets supposed your neighbor's massively retarded child asks your massively retarded child for permission for his Daddy to use your yard, and your child agrees. Neighbor then comes over and stages a cookout on your lawn, or for that matter just walks across it.
This is a very interesting anology, as computer systems are very "dumb," but unlike developmentally challenged individuals, computers are also very easy to control (i.e. they do precisely what you tell them to and nothing else, if you count the code as instructions). It is a simple matter to encrypt a wifi point (and a well reccomended practice), whereas a retarded child is probably difficult to train to restrict lawn access, and that is not generally a well-reccomended practice.
To be honest, I don't think any analogy quite sums up the situation. If you're on someone's wifi, and you're not causing harm, and they left it open, what is the problem?
All of the locked door, stolen bike, and lawn analogies miss one important fact. 802.11 uses the radio spectrum. In the US we ALL own the radio spectrum, but "trust" the FCC to manage it.
The FCC says you can transmit on that band within X power. They also say if a a signal enters your reciever you can read it.
Together they imply you can join an unsecured network, because that person is allowing their equipment to broadcast, and recieve on open frequencies.
Slashdot is not about stories, Digg and other linkfarms are about stories. Slashdot is about comments, Slashdot is about community. Considering the sorry state of the moderation system, it's hard to read many of the good comments without also coming upon highly-rated but rather banal comments (including a few I have authored). People who are too busy to browse through hundreds of comments will enjoy the backslash approach, and I, for one, think it can help extend debate on issues that are important (at least for nerds).
We don't need internet providers and we don't need internet providers which leak our communication data to the governments and endanger the freedom of the net. The net should be a net and wireless technology is great for the creation of a real P2P internet.
OK, so how exactly are you connecting to Slashdot without using an ISP? Are you standing at a terminal in the cage at SAVVIS where Slashdot's servers are located?
sarchasm: The gulf between the author of sarcastic wit and the person who doesn't get it.
There's something about Slashdot that encourages these terrible analogies, and it's just awful to watch. Sometimes, I see a story, and I can tell beforehand that there's going to be a bunch of these crappy analogies being thrown around, argued over and refined. It's usually around then that I turn my computer off and go outside, so in a sense, they literally send me running.
For example, an Anonymous Coward said:
What is this backslash garabage? It's just a rehash.
Another user commented:
I hate backlash.
Many readers readers responded to this comment with a wide range of opionions,
etc
If so, then you're giving your neighbors cancer and they're entitled to take some of your bandwidth as retribution / reparations. Do not mod this funny.
Well, get yourself a login and use Preferences > Homepage, disable "Backslash" and quit whining.
Don't just game, Dungeoneer
Edit your profile and uncheck the Backslash sections so you won't see it again. No big deal.
Actually, most of Wyoming is on fiber optic and wireless networks. One of the first broadband offerings in Gillette, Wyoming was from a company called Visionary Communications. They placed towers all around town for their wi-fi subscribers (no, its not open).
One of the interesting things about Wyoming is that within the boundaries of the towns, subdivisions and neighborhoods are closely packed in together. Sure there are the folks that live out on their own ranches but the trend is to live closer to town.
I'm amazed at the amount of people insisting that an open wireless router is an implicit invitation to join, and the number of people saying "if you are doing no harm, what's the problem?"
I love the idealistic vision of information being free, of internet access being free, etc - but the "hacker ethic" is no excuse for stealing.
Problem 1: Your average person is not very tech savvy, so your average internet router comes unsecured so that it works straight out of the box for your average version. This means that the vast majority of wireless routers are open unintentionally by people who don't read instructions or know anything about security. And why read the instructions if they don't have to? If it works right out of the box, why spend time reading the damn booklet? This means that the majority of unsecured wireless connections are likely that way because people don't know any better, not because they're Just Like You(tm) and want to share.
Problem 2: Even if these people left them open for convenience, sharing, etc - their terms of service with their ISP almost always have a clause saying that service is to be used only be residents of the billing address. By using their connection, whether they want you to or not, you are aiding them in breaking their TOS.
Problem 3: No, seriously, get it through your thick skull - that network isn't open because the guy who owns it reads slashdot and agrees with you. It's open because the guy doesn't know any better. However, his "stupidity" (reality: lack of interest in technology to the degree of yours) does not give you the "right" to steal.
Problem 4: You can say "if it doesn't hurt his bandwidth usage, it's fine", but that becomes a slippery slope. How many people get to borrow Unsuspecting Bob's internet connection then?
Problem 5: If you were to win the argument that people should be free to share their connections with the world, you would kill ISPs as a business. It's tantamount to arguing that it should be perfectly legal for one guy at the top of an apartment building to pay for cable internet, and for every resident of that building to mod a Linksys router and get the whole building on a WDS mesh through one connection. I'm no fan of the cable company, believe me, but doing this is still not fair to business.
http://www.babysmasher.com
http://www.openingbands.com
Your analogy misses the point entirely.
The situation the GP was describing is a more like trying to sell yak's milk in a Bavarian beer garden. You can bring as many Nepalese sherpas as you want, each with their own entry visas, and the yak might clear customs, but unless the milk is pasteurized you're still going to run into problems. And who's to say the Germans have a taste for yak's milk anyway? It's shortsighted thinking like this that leads to posts like yours.
Breakfast served all day!
So it's like apples and oranges then?
What bugs me about this is how some people spend time writing up bitingly barbed and highly satirical screeds about the monumental stupidity of common users. "Imagine this bozo trying to set up a home network like he was a real sysadmin," they sneer. "And the whole time he doesn't realize that the brand of router he's using has a vulnerability somewhere deep in the firmware. If I'd been him, I'd have spent more money and more time, but instead this poor sap gets to deal with what his ignorance has unleashed...." and so on, ad nauseam.
The reason it annoys me is because, when these people are caught piggybacking onto their next-door neighbor's wireless, they then post that "this whole debate is silly, anyway, because the airwaves are free to everybody, and it's unfair to expect someone not to take advantage of such an unexpected bounty, and anyway the neighbor wasn't using that much of it in the first place, and he had it coming for not securing his network...."
But then again, I guess that's different.
Strike while the irony is hot! -- The Freethinker
I live in Austin. There are hundreds of businesses here with free WiFi. The city has free WiFi blanketing downtown. This isn't really a trespass issue. How exactly do you know which networks are free to use without using encryption as a clue? If anything the issue of trespass is only an issue because WiFi is public in much the same way as a large green space and includes no way to provide a "No Trespassing" sign.
Not only does it tweak your neighbor, it also produces a high-pitched whining noise from people who choose to find it offensive to their moral sense.
One of the best responses to the "But no childish games please." bleat was the note that "Pranks are a big part of the hacker ethic." , which indicates that Electroschock's "understanding of hacker ethics" is a bit off. (Note that the prankster explicitly referred to this as an alternative to securing the network:
I.e., the network is "open" in the 802.11 sense, but isn't "open" in the sense that he wants people to be able to happily surf normally using his connection, or in the sense that you can expect your traffic through the network to be unmolested at any protocol level. Think of it, if you will, as a form of encryption. Yes, you can choose to view the act of not securing a network at the 802.11 level as an invitation to use the network as you please without any obligation on your part either to compensate the person providing the network or to provide a network others can use. You can also choose to view the act of not locking a bicycle as an invitation to use it as you please without any obligation to return it when you're done, compensate the person providing the bicycle, or provide a bicycle that others can use, but, if you do, in neither case would I take your moral views on that subject very seriously, and I suspect most other people - including, perhaps, even fans of free networks or bicycle-sharing programs - would do so, as moral views of that sort leave some people free of moral constraints on the issue in question.)
Electroschock's speaking of "P2P" in this context was also a bit off; he said "The net should be a net and wireless technology is great for the creation of a real P2P internet." "P" in "P2P" stands for "peer"; unless your neighbors are letting you use their wireless network, what's going on isn't peer-to-peer, it's somebody deciding that they're entitled to your bandwidth but they don't have to provide any bandwidth of their own.
In an ISP-less world of free networks, I think it'd be inappropriate to muck with the network access of people whose packets happen to be traversing your network if it's part of a free (inter)network. That's not a world people use ISPs to route their packets to the rest of the Intarweb, and in which some people use other people's ISP connections to route their packets to the rest of the Intarweb, however, and that's the world the prankster is speaking of.