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Contest For a Better Open-WRT Wireless Router GUI
Reader RoundSparrow sends word of a contest, with big cash prizes, being mounted by a commercial vender of open source Open-WRT routers. You have 10 months to come up with "the most impressive User Interface/Firmware for Ubiquiti's newly released open-source embedded wireless platform, the RouterStation." Entries are required to have open source licensing and will all be released. First prize is $160,000, with four runners-up receiving $10,000. RoundSparrow adds: "Could be built on top of existing X-WRT or LuCI OpenWRT web interfaces. OpenWRT Kamikaze 8.09 was just released. Now is perfect timing for OpenWRT to get some kick-ass interface and usability ideas. I'm not affiliated with the contest vendor."
What's wrong with X-WRT?
OpenWRT is something you set up, then forget. It doesn't need "themes" or "skins", or 3d effects. This is not "pimp my router".
I want to delete my account but Slashdot doesn't allow it.
Other OpenWRT news. The newest Atheros 9xxx radio chips is available in a number of OpenWRT supported routers now. I have been working to help organize new 802.11n support in OpenWRT. I have compiled a list of consumer routers that work with Linux ath9k driver and ar71xx CPU. In order of current recommendation:
Planex (PCI) MZK-W04NU, 32MB RAM and 8MB flash, USB port, 10/100 Ethernet
Trendnet TEW-652BRP, 32MB RAM and 4MB flash, 10/100 Ethernet
Trendnet TEW-632BRP, 32MB RAM and 4MB flash, 10/100 Ethernet
D-Link DIR-615 revision C1 (ONLY!), 32MB of RAM and 4MB flash, 10/100 Ethernet
TP-Link TL-WR941N WR941ND, 32MB RAM and 4MB flash, 10/100 Ethernet
OpenWRT team is pretty close also on the Netgear WNR2000.
These listed above all come from a common Atheros AP81 reference platform. see http://wiki.openwrt.org/AtherosAR9100
In USA and Japan, the Planex is available on Amazon.com for $59.99 with free shipping... it has more flash and USB port. 3 removable antennas, is a nice hacker system. In the USA, the Trendnet routers have been on sale from Newegg, Fry's, buy.com for only $25 a few times. I will try to post on Reddit / my Slashdot journal when I see them on sale for $25 next time.
The ath9k driver for Linux is not yet mature but is moving along... in 2 to 3 months I expect we have a very nice platform... and the router interface and ease of use of OpenWRT is getting attention with this contest! Now is an exciting time for OpenWRT and Linux routers - finally moving to some new N devices.
should work as easy as a personal firewall
not everyone can understand or spend the time to learn iptables
Tomato for the win!
The higher the technology, the sharper that two-edged sword.
I mean seriously... you're putting out a new product... why not put in gigabit lan ports?
You guys altered the name to Open-WRT :) Anyway, thanks for spreading the world on this and Kamikaze 8.09 release. the OpenWRT devs work hard.
Oh god no.....no Web 2.0 Crap. the router GUI is supposed to be fast, small, and compatible with EVERYTHING.
DDWRT has a problem with Firefox on the latest builds because of the stupid Web2.crap to make things more flashy instead of working right.
I am really tired of the "ooh shiny" becoming far more important than functionality lately in both projects.
Do not look at laser with remaining good eye.
interesting contest, but I searched and couldn't find an answer to my biggest questions:
does it run linux?
are there any requirements to use it in a beowulf configuration?
any requirement to be resistant to, and remain working, after having hot grits dumped on it?
should it support QoS by streaming naked photos of natalie portman at top priority?
have all used cli
It's not like it's your money! I currently use Tomato on one of my routers. I love the interface. I don't log in very often, mostly to check those fantastic real-time usage stats.
But when I do log in, it is nice to be able to find things quickly. I respect developers who take into account usability and style. In fact, I have basically no respect for those who discount it.
You probably can code circles around me. But in the end, the customer or user only sees the interface. They only see those "useless" graphics, and that "Web 2.0 Crap". Yet, a well designed interface will allow new users to appreciate the product faster, and hopefully keep them around.
Just because the majority of web developers suck at designing "web 2.0" interfaces doesn't mean that the problem lies with the "web 2.0" part. We'd have a lot less technology if we used that metric to measure a tools value.
Fail, you stole that from Full Metal Jacket, what an uncreative dumbass..
I think the comments so far some up one of the major issues with the open source world and usability. At this point most of the comments are saying "we don't want themes" and "it's fine the way it is". The usability of a device has NOTHING to do with being able to skin it or apply themes. Usability is all about making the device simple for someone with limited knowledge or experience to use. This means things like dimming or disabling options if someone chooses a checkbox for an item that is incompatible those options. If they choose to only run the device as 802.11b (god knows why, but humour me), then don't ask them to set up the security options that only apply to 802.11g and higher. Explain what the options do in plain English. That's what usability is.
In fact, I have basically no respect for those who discount it.
You probably can code circles around me. But in the end, the customer or user only sees the interface.
Actually you've hit on a major problem of programers that we don't like to talk about (well, except me, obviously..). The thing is, GUI design is a complex art, one that takes a long time to learn to do well, so its hard to be good both at visual interfaces and the often very complex code that they control.
I know this from my own work. I'm a pretty good coder (gosh, how modest of me). I can write code to just about anything, and charge a pretty penny to do so, but my ability to code a user interface is rather poor. Sure I know all the theory, but there's something extra you need, that 'eye for the visually pleasing' thats hard to cultivate unless user interfaces are what you do all the time.
I've used plenty of applications where the guy who wrote the backend code also coded the gui, and as a rule the gui is somewhat lacking. This is't just restricted to single coder projects, it also occurs when a project is full of able back end coders, and they build the gui to suit their own level of ability to use the code.
You can see this if you use Emacs. Nice though that software is in features, the interface is godawful, and actively prevents anyone new to computer usage or programing from using it.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
"Simplicity and intuitiveness for the end user (both newbie and expert)"
Maybe this will be won by the most blinged-up interface but there's hope here that the competition organisers get some well thought out entries which help guide the users through the configuration of their routers.
Some installs are jargon heavy and just assume you know what all the options mean, little to no explanation or help. I've spent many hours sweating over some WRT GUIs that have (to me as a relative beginner) had meaningless options. I really really want to use these excellent installs but I get really put off by zero-to-poor documentation or explanations of what all the options are.
A simple interface with excellent documentation and guidance would be worth the prize.
Can it be Flash based? I've got some cool ideas involving fancy animated text effects and transitions that would be really useful for a router interface.
Better known as 318230.
Open-WRT needs a Redmond theme. Bonus points for defaulting to Aero theme, which the user immediately disables, reverting to Redmond theme.
You can see this if you use Emacs. Nice though that software is in features, the interface is godawful, and actively prevents anyone new to computer usage or programing from using it.
What would you honestly change? 99% of the feature set is packed up in control sequences. If you're using the GUI at all one would have to wonder why you are using Emacs. Vi doesn't even bother.
I understand the point you are making but Emacs is really not the program to pick on because it has a *fantastic* User Interface for programmers--which is the entire point of the program. No your grandma will not be able to point-and-click her way through writing a new database application, but I think that is ok.
As far as "new programmers" go, I would say (i) if they can't easily get through the included Emacs tutorial, programming is probably not going to work out for them (ii) they should not start off in Emacs anyway. Emacs solves a lot of problems but until you've written your first big program you're unlikely to have much appreciation for its features.
When things get complex, multiply by the complex conjugate.
If you really like CLI and have decent knowledge in networking then give Vyatta a try. No GUI at all.
I've tried it and it's not too hard. Just have to pay close attention to the syntax or you'll screw it up.
GUI in routers do provide a quick glace as to what is going on. High end Cisco routers do NOT have a nice web-gui as it is entirely CLI based except for some home versions of the PIX.
I personally use DD-WRT v24 SP1 in all of my wireless access points (they're really routers but I turned those functions off) and never skipped a heartbeat. I got a Linksys that been running 6 months solid without a single reboot as DD-WRT is meant to be set and forget type thing.
I do wish peeps luck in this contest as we all could use the money.
I'd like to find an affordable (US$80)router to use my Merlin V640 ExpressCard EVDO modem. I have a USB adapter for it that works, so other than the Kyocera KR2 Mobile Router (now $188) and similar, do I have more choices?
RE: "If you really like CLI and have decent knowledge in networking then give Vyatta a try. No GUI at all."
OpenWRT has "no GUI at all". it is an optional piece when you build the firmware. It has all the settings in /etc/config/ tree. There is a command-line program called UCI that allows you to easily edit them. The GUI's get built on top of that typically.
There are at least 3 installable package GUI's available that I know of: X-WRT, LuCI, Gargoyle. But people have used it for years and years without a GUI.
OpenWRT's is really great at being portable to many routers and CPU types. They spent a lot of time investing in the long-term and not worried about the visual fluff.
Pimp My Router.... that's an awesome idea
I'd like to see an open-wrt router firmware with.
8+ - eth ports for multi wan (load balancing and failover)
8+ - port USB so I can attach everything
Different size distribution so we can choose what to install and a nice auto-update to support all the devices.
Love many, trust a few, do harm to none.
You don't have openfirmware for this* router.
*Clue: This is a house brand.
Shai Schticks:"You don't make peace with friends, you make peace with enemies"
I don't know, LuCI seems pretty good to me and is a good choice for people who actually know about the technical stuff but don't want to do everyting in the CLI. Basically, it's nothing more than a graphical add-on for uci (the OpenWRT configuration manager) that shows you what options are available and what they do. Oh, and the live network/CPU load diagrams are a nice touch too.
As far as "new programmers" go, I would say (i) if they can't easily get through the included Emacs tutorial, programming is probably not going to work out for them (ii) they should not start off in Emacs anyway. Emacs solves a lot of problems but until you've written your first big program you're unlikely to have much appreciation for its features.
I get where you're coming from but when I was a post grad teaching first year students my experience was that that they found Emacs to be uncomfortable and used it only when the tutorial sheets required them too. Most of the time the dominant linux text editor in use by students I taught was kwrite.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
It's cute that they're doing this the open-source way, but realistically they'd be better off hiring a few designers and letting them fight it out. Maybe I'm jaded from years of Linux adminning, but I have absolutely no faith in the graphic abilities of network geeks, myself included.
-Billco, Fnarg.com
The majority of the posts seems to be sneering down in elitism to these poor folks that don't know how to setup a router in the CLI and, god forgive them, try to setup their home network by themselves, without paying a sysadmin to do the work.
Yes, a sysadmin that can't configure a router without a good GUI should be hanged by the neck until death, but last time I checked, the majority of the routers supported by OpenWRT were SOHO ones.
Do you really expect people that just want to setup a minimal network of maybe a printer, one desktop and two lappies to read RFC 1123?
One shouldn't need to. Yes, networking is interesting and useful, but not everyone wants to be an expert on it.
I have seen a physics PhD setting up a wireless net for his lab with WEP, because the list of protocols was sorted alphabetically and it came before WPA. Well, he should have told the lab's undergrad to do the job but, nevertheless, a good GUI would at least put an (deprecated) near the option.
He wasn't being dumb. Would be if he put a short common word as password. Even if he didn't knew about dictionary attacks, common sense would have told him that they're easy to guess. Actually he chose some interval of the digits of pi because it had high information entropy. But how could he know that the router would offer an insecure option to him or which 3-letter acronym was better?
entropy happens
The thing is, GUI design is a complex art, one that takes a long time to learn to do well, so its hard to be good both at visual interfaces and the often very complex code that they control.
You hit the nail on the head. It's an art, and that means that, when all is said and done, it's the guy with the eye who polishes the job. Programmers can follow all the user-interface design rules laid down in the multitude of books on the subject, but if they don't have the touch, what they'll come up with may be functional, but will still look like crap. It's as inevitable as the tide. Good coding can be an art as well ... it is by no means always thus, but some developers do carry their work into the realm of true art.
Look at the history of video game development. Early products were as you describe: often designed by single coders, or maybe a team of coders. That worked, because the hardware was too crude to allow an artist to do much with it, although some companies did hire animators. Blocky programmer-drawn graphics were acceptable because that was about the limit of the equipment. However, as the resolution, color space, and processing power of graphics systems improved, you began to see specialization occur in game development. Much as happened in motion pictures decades before, the evolving complexity of the products demanded an expanding team effort. Designers, coders, artists, animators, level designers, writers, play testers, quality control testers, a whole host of wildly different disciplines are now required to produce a single game.
It's no different in the world of Web development. You need a team, with people capable of handling overall design responsibility, documentation (something coders are notoriously bad at doing), back-end requirements, the GUI, and many others. It's easy for developers who have no talent for user interface work to dismiss such as unnecessary glitz. Understandable, but entirely wrong when talking about software that is marketed or used by the general public (like a Web site.) Furthermore, in the real world people (especially people who write big checks) are impressed by a polished, well-written GUI.
Personally, I've spent almost thirty years in this business, and I started out doing largely embedded-type stuff for the game industry, and eventually got into doing higher-level graphics and artwork. Then I got into manufacturing and control systems, and discovered that users like software that is attractive, not overly-complicated for the problem it purports to solve, and above all does the job. The years I had spent learning graphic techniques paid off handsomely during that time, since my competitors generally couldn't draw their way out of a shoebox.
In any event, I found that while I had successfully worn a number of hats as an application developer over the years, it was getting harder and harder to be a solo act. So, nowadays I'm not, I work with lots of other people, and I've found that my skill set is complementary to many of them. It works out well, if you have a good team.
The higher the technology, the sharper that two-edged sword.
IMO, the best router interface is a CLI.
Says who? If it is cheap enough (and energy efficient enough), why not throw a damn Core Duo in the damn thing and use powerful statistical magic to figure shit out?
"Fast and small" for "fast and small"'s sake is old school man. Nobody gives a rats ass about wasting CPU or memory. The computer works for us and what you should really be concerned about is saving *our* CPU cycles and memory--not the computer.
<blockquote>I am really tired of the "ooh shiny" becoming far more important than functionality lately in both projects.</blockquote>
Your definition of "functionality" is too narrow to be of use. If you broaden your definition to include the user experience, "ooh shiny" matters a whole hell of a lot. Contrary to some, presentation matters almost as much, if not more, then your very narrow definition of "functionality".
My guess is that they want it as easy to use and configure securely as possible. Its time to ask yourself, what would Steve Jobs do?
Think Deeply.
Maybe the task is needlessly complex? Why should somebody connecting to a access point need to configure which encryption protocol to use? Why should the damn WiFi card and the access point negotiate automagically and *pick the damn best one they both support*?
^ this space reserved for replies telling me that the protocol doesn't allow it. Well you know what? The user isn't broken, the protocol is. 802.11/whatever is horribly insecure because the protocol doesn't fucking handle the encryption for you. Let me pick a key on the router, type it into the laptop, and the damn things can pick WAP, WPA, WEP, WAZOO or whatever the fuck some encryption dudes dream up all on their own. As long as it works and is secure, I dont really care what the hell protocol is used.
Blame the user is arrogant, stupid and is increasingly a black mark on employment. The world expects the programmer and the designer to do everything for them. That is the market. Deal with it. Programmers who design usable stuff will find their skills highly desired. Programmers who say users are spoiled children will rapidly find nobody wants to hire them.
You know who to blame? Blame the designers and programmers for not understanding what the goals and tasks are. Blame the designers (or lack thereof) and programmers for not removing all the roadblocks in the way of accomplishing said goals and tasks.
Honestly, the real reason programmers get bent out of shape (*cough*aside from the weird vibes coming from those still in the computing stone age like RMS*cough*) is that programming a usable interface is very hard. Lots of edge cases and you can't catch all of them. Really, the shit is hard and no silver bullet will ever be found that makes the hardness go away.
It looks like the overall discussion quickly drifted away from the actual topic and the further degrades into insults and endless discussions about cli vs. gui / enduser vs. professional etc. But hey, this is slashdot so I think it's expected.
Anyway, I think that most people miss the point here. The challange is about to implement a (new) gui for the Ubiquity Router Station, based on AirOS which is actually a snapshot of the OpenWrt Kamikaze trunk with some patches added for board support and another proprietary hal to drive the Atheros cards used with the board.
The RouterStation is not exactly a SOHO device, it's a bare embedded board featuring a fast MIPS cpu and three MiniPCI slots, POE and some other fuzz.
It has higher specs then the average Broadcom gear and is intended for larger infrastructure deployments, like wisps etc.
So far on the target hardware. Since one requirement is to use OpenWrt/AirOS as base operating system, one can rule out Tomato (which ppl quickly suggested) since it's built on top of the former disclosed Linksys SDK for WRT54G devices and relies heavily on a Linux 2.4 kernel to use bcm43xx wireless phy. Part of the original Linksys firmware design was the use of nvram as central configuration storage which is abandonned in nowadays Kamikaze releases. Anyway - I think it's nearly possible to rip the gui off an existing firmware project and refactor it to run on top of OpenWrt, it would be easier to just start from scratch.
Now the list of required features is pretty long and includes stuff that's not present in (half) open source firmwares like Tomato, DD-Wrt or OpenWrt. It includes things like bgp/ospf routing, bonding, snmp or layer 2 firewalling (ebtables, arp nat ...) just to name a few. That are things a normal ui designer can't draft without the support of one or more networking experts who actually know whats this about and how it's done properly. Some of that features also are inherently complex and can't be fully abstracted away with some fancy ui elements and a short help text on each page. On the other hand an ui allows to present complex relations like traffic flow, qos behaviour, wifi signal stength etc. in a visual way that can't be accomplished with a cli-only interface.
The to-be-developed ui is not intended for casual users that just want to hook up a bunch of computers and get into the internet. It's also not intended to be used by people who don't have a clue about networking or don't want to learn about the principles of the involved technologies. You have to keep in mind that the interface should be able to handle multiple wifi cards with multiple wireless networks each, that it should ease the setup of complex network configurations without limiting the amount of possible options. It's also not about a fancy web 2.0 portal or shiny flash interfaces, just to please possible customers.
Imho the ui should also be designed in such a way that it allows a smooth coexistance with cli-based workflows. Neither Tomato nor DD-Wrt provide such abilities since the underlying system is optimized to be used by the ui and hardly intuitive to use via the cli. Think of it like the relation of Linux and Xorg. You can uninstall all X related stuff and still have a functional system where you can access all resources etc.
Another fact to worry about is the portability of such an ui - if one wants to make it into a generic interface for OpenWrt, it would have to support a wide range of hardware from simple Linksys boxes to X86 gear like Avila or Alix boards, tt would have to support wireless configuration for madwifi, legacy broadcom and mac80211 based wireless drivers, each with different ways of configuration. Oh - and it should support kernel 2.4 and 2.6 which becomes a real pain if one relies on sysfs for state information.
Also the choice of the programming language and framework matters, one could go ahea
GUI in routers do provide a quick glace as to what is going on. High end Cisco routers do NOT have a nice web-gui as it is entirely CLI based except for some home versions of the PIX.
Well, the PIX isn't really a *router*. But as long as you mentioned the Cisco firewall product line (which includes the ASA), have you tried ASDM? It's maturing into a pretty useful way to admin a Cisco firewall through a GUI.
http://www.cisco.com/en/US/products/ps6121/index.html
When you said "home version of the PIX", I assume that you are referring to the PIX 501 and possibly the 506. Those devices can run the PDM GUI interface which is kinda clunky.
If only the iPhone had a more useful CLI and ditched the glitzy interface, it could be the best phone on the market!
Boot Windows, Linux, and ESX over the network for free.
Editors, do your fucking job already. It's vendors -- you even have it quoted.
All good points and one left out. One needs to purchase the hardware in order to be in the game.
Shai Schticks:"You don't make peace with friends, you make peace with enemies"
While slightly OT, I took a moment to seek out possible alternatives but it seems DD-WRT is still the only 3rd-party firmware to solidly support the WRT54G(S) v5 and above. Is any fellow /.'er aware of firmware that would work well with v.5 and above considering that friends and family happen to have purchased the newer/stripped down versions.
>> there's something extra you need, that 'eye for the
>> visually pleasing
Not only you need "an eye" (i.e. the discriminative system in learning theory parlance), you also need the ability to come up with something new (i.e. the generative system).
I have "an eye". I can tell whether something is good or not, and can convincingly explain why. I can suggest improvements to an existing interface and explain how they will improve matters. I just can't roll a good UI from scratch.
The brand doesn't matter. What chipset is inside matters. And even though there are thousands of different routers to choose between, there are less than 10 chipsets they are based on.
The rules of the contest say this:
Required elements for web interface pages:
Does this mean entrants do not own the copyright to the web design portion of the contest?
(Btw, in case you thought this was just about adding a web-based front-end to an existing product, think again: this is about designing intuitive user interfaces for complex networking options. Not a trivial task.)
I'd say it's because DD-WRT has a nice GUI and is easy to configure... OpenWRT, not so much.
/etc/config/network and /etc/config/wireless, adding about 20 lines to each file. (source: http://forum.openwrt.org/viewtopic.php?pid=53924 )
I use a wireless router as a repeater, and upon searching for which firmware version I would like to use, I found that:
DD-WRT you click repeater, set the SSID of the source network, the SSID of the new repeater network, and assign it a WPA password. Done. Happy point and click. (source: I did it.)
OpenWRT I found that you have to edit the
The OpenWRT was doable, but would certainly take more than the 30 seconds I needed to setup, then forget, the DD-WRT firmware that I went with. I think this story is an advertisement because they are losing a popularity contest with DD-WRT. And yes, you can telnet into the DD-WRT and edit the files manually as well if that's your thing.
I use dd-wrt and find the interface good enough for everything I've tried to do with it... But I've been thinking that this stuff would get more wide-spread attention if end-users could have various scenarios auto-configured for them. ie: I want a firewall but I also want to provide an open access point while protecting my home network from anonymous users. I want to restrict anonymous users to 100kb/sec of bandwidth. I want my security cameras to be blocked from talking to the outside world .. blah blah blah... none of this "WDS" "VLAN" "DMZ" "QoS" "WPA2" unless you're in expert mode.
I just saw this article and wish I had known about these guys before I wasted money on my last router. Retail consumer routers don't have enough features, high-end routers are too expensive and running WRT on consumer routers still leaves them with a few features missing due to memory limitations. I've been toying with building my own but now I definitely know where my next router is coming from.
Tomato for the win!
Doesn't support IPv6 AFAIK, which a lot of us would like to play with.
I'd like a good Linkxsys WRT replacement. The RouterStation mentioned in this sounds interesting but looks more like a board in need of a case in need of radios sort of thing - yes? The Pro model was the only one I saw a price on and it too doesn't look like it has radios onboard. Are these aimed at consumers or at WiFi dealers? If possibly for consumer use can you point to some dealers maybe?
Currently running DD-WRT on one of the early WRT54G units and an upgrade might be nice indeed!
Build it, Drive it, Improve it! Hybridz.org
The #1 problem with WiFi in my area is the lack of available channels. Half the problem is the all the unsecured routers still set to SSID "linksys" and on the default channel. So, add in a feature that can connect to each visible network that has a default SSID and admin password and moves its channel to free up a channel for my use.
some sort of the gui which has the firewalls - bricks like blocks would be awful. You are like playing the tetris but in reality configuring the iptables, got the point? I dont care about the implementation java/app/script/flash but the idea should be "routing is the game!" :)
You don't have openfirmware for this router.
The number of closed routers and outright crippled routers far exceeds the number of open and well supported routers.
This problem continues as long as consumers buy the flavor the week and with no concern as to quality or the product even meeting the claims printed on the box. Routers aren't new, this has been over 10 years of this mess.
Take the famous Cisco/Linksys WRT54G/GS beyond version 4. That router is still for sale more than six years after introduction. Now it is a ghost of it's former self on internal parts. A stream of supposedly self-proclaimed experienced Linux users continue to buy these (version 7, 8, etc) each day and then whine away that the various Linux projects don't support it. 2MB of flash for a $60 router that sold 6 years ago for $60 when it has 8MB of flash... yha, ok. Keep supporting and recommending that model to people. The Least Common Denominator sadly drags down all.
I meant "lowest common denominator".
GUI design is a complex art, one that takes a long time to learn to do well...
I'm not a programmer, so I respectfully defer to your knowledge.
Question: GUI can be greatly improved by:
Right?
After reading the technical requirements, it's clear this isn't really a user interface competition. User interface is a part, yes, but I would say the much smaller part of the contest. Take a look at this part of the official "technical requirements" of the contest to see what you would have to implement, in addition to a UI. Actually, I would say the 200,000 they are putting up for the contest is an absolute steal... implementing all these features would typically take a team of quite a few engineers (or a few working much longer), and you'd probably end up paying them much more than 200,000 dollars combined regardless.
Technical Requirements:
Beware of bugs in the above code; I have only proved it correct, not tried it.
Done. Where's the price?