Member of the Board of the Polish Linux Users Group. Human rights in digital era hacktivist, Free Software advocate, privacy and anonimity evangelist; expert volunteer to the Panoptykon Foundation; co-organizer of SocHack social hackathons; charter member of the Warsaw Hackerspace; and Telecomix co-operator; biker, sailor.

Formerly President of the Board of the Polish Free and Open Source Software Foundation; CTO of BRAMA Mobile Technologies Laboratory on Warsaw University of Technology and a student at Philosophy Institute on Warsaw University.

Table of Contents

02.07.2016Dzień, w którym cenzura Sieci w Polsce stała się faktem pl 152 13.04.2015Needless haystacks en 151 12.03.2015e-Dockleracje pl 150 19.01.2015Ban on encryption is not about banning encryption en 149 13.01.2015Not Free as in Beer en pl 148 30.12.2014GPG Key Transition en pl 147 18.12.2014Siła wyższa pl 146 04.12.2014Internet in Poland to be porn-free after all? en pl 145 27.11.2014Block everything! en pl 144 02.11.2014Introducing: rysiek's law of unavoidable consequences en pl 143 09.09.2014Stop paedophilia en pl 142 22.06.2014Even with EME, Mozilla will become "the browser that can't" en 141 21.06.2014EuroDIG 2014 en pl 140 19.06.2014Hacker in the Digital Affairs Council en pl 139 30.05.2014Public consultations and anonymity en pl 138 18.05.2014Why being a pirate is not worth it en pl 137 15.05.2014On Mozilla, DRM and irrelevance en pl 136 14.05.2014Not-quite-good-enough-Mundial en 135 12.04.2014Irresponsible non-disclosure en pl 134 29.03.2014Ecologic, Ford and surveillance en pl 133 15.03.2014Otwórzmy edukację pl 132 10.03.2014Blurry line between private service and public infrastructure en 131 08.03.2014IM IN UR MINISTRY, CONSULTING UR INTERNETZ en pl 130 17.02.2014Encrypted VoIP that works en pl 129 11.02.2014So you want to censor the Internet... en pl 128 02.02.2014This is why we can't have nice IRC en 127 31.01.2014Decentralize where your mouth is en pl 126 30.01.2014A link cannot be illegal en pl 125 30.01.2014Copyright reform debate lives on en pl 124 26.01.2014Neat HaCSS, or let's de-JS the Web a bit en 123 27.12.2013Information Account Number en 122 14.12.2013HaIPu en 121 20.11.2013Friends of TTIP and data protection in Brussels en 120 19.11.2013Social media, Polish Pirates style en pl 119 05.11.2013A rude comment en 118 20.10.2013TEDx Warsaw Women and privacy en pl 117 03.10.2013Copyreform at CopyCamp 2013 en pl 116 22.09.2013Long-expected KMail2 rant en 115 18.09.2013Facebook for schools en 114 12.09.2013In which I call upon United Poland parliamentarians to guarantee citizens the right to Internet free of surveillance en pl 113 08.09.2013Complaintivism en 112 04.09.2013It's his own fault en pl 111 19.08.2013Lies, damn lies, and analytics en pl 110 27.07.2013Shortest Internet censorship debate ever en pl 109 22.07.2013Cómo el compartir información desarraiga los modelos conservadores de negocio en es 108 22.07.2013Posts' markup is now available en pl 107 11.07.2013Kultura wolna i legalna pl 106 07.06.2013Internet is not a problem en pl 105 05.06.2013Libel Culture en 104 17.05.2013Wojtuś Fatalista i wolność w Internecie pl 102 17.05.2013Por qué hallo la licencia -ND como innecesaria y dañina en es pl 101 28.03.2013Wolność nasza codzienna pl 100 17.03.2013Nie wszystko korpo co o wolności w Internecie pl 99 15.03.2013♫ Odpowiadam na e-maile ♫ pl 98 11.02.2013One year anniversary of Anti-ACTA en pl 97 30.01.2013Nie ma haka na słabe dziennikarstwo? pl 96 30.01.2013Fighting Black PR around OER en pl 95 29.01.2013HOWTO: effectively argue against Internet censorship ideas en pl 94 20.11.2012Border conditions for preserving subjectivity in the digital era en pl 93 19.11.2012Social blogosphere en pl 92 07.11.2012Embrace fragmentation en pl 91 02.11.2012SERVICES.TXT en pl 90 24.10.2012Apple por fin saltó por la borda en es 89 24.09.2012Rompiendo los muros del jardín en es pl 88 24.09.2012Minister i Kultura pl 87 24.09.2012Melbourne CryptoParty video message en 86 16.09.2012On sailor's sensitivity, or "the starry heavens above me" en pl 85 22.08.2012Black PR around Polish e-Textbooks en pl 84 15.08.2012Regaty utracone pl 83 24.07.2012Hypochristian Love en 82 24.07.2012Some new Layout Goodness en pl 81 17.07.2012Party 2.0 en pl 80 16.07.2012Prawo autorskie po ACTA pl 79 13.07.2012Party as a system hack en pl 78 10.06.2012Are corporations dangerous only in collusion with governments? en 77 09.06.2012Proxies! Proxies everywhere! en 76 05.06.2012Automagic re-publishing from Twitter to StatusNet en pl 75 18.05.2012TPSA/Orange and GIMP, or a word on 5 users en pl 74 16.05.2012Słowo o Warsztatach MAiC pl 73 15.04.2012Schowaj gadżeta pl 72 05.04.2012Perfect ToDo-oid en 71 27.03.2012Subjectively on Anti-ACTA in Poland en pl 70 25.03.2012On copyright in Budapest en pl 69 23.03.2012Kościoła poczucie odpowiedzialności pl 68 20.03.2012Learning to Internet en pl 67 19.03.2012Kościoła wiara w wiernych pl 66 29.02.2012Brussels Safari #1 - EP press conference and ITRE en pl 65 21.02.2012Because ACTA is passé en pl 64 20.02.2012Privacy of correspondence, EU-style en pl 63 17.02.2012Polish PM on ACTA: I was wrong en pl 62 12.02.2012Anonymous vs Corponymous en pl 61 10.02.2012To have a cookie and dowload it too en pl 60 19.01.2012About ACTA at Polish PM Chancellery en pl 59 19.01.2012Free as in United en pl 58 16.01.2012Towarzystwo czuje się oszukane pl 57 10.01.2012Terms of Using the Service en pl 56 05.01.2012Corporate lack of patriotism en pl 55 04.01.2012Terroristcopters en pl 54 03.01.2012IceWeasel and Privacy en pl 53 28.12.2011Good Uncle Stal... Putin en pl 52 25.12.2011Useful Bash defaults done right en 51 21.12.2011Google Mail, or how mail becomes publication en pl 50 20.12.2011Occupy Gotham en pl 49 11.12.2011Copyfraud en pl 48 08.12.2011Multikino Wikipedia FAIL pl 47 27.11.2011Nie miejsce na pl 46 18.11.2011One-way cutting en pl 45 12.11.2011Tolerancja dla Kościoła pl 44 11.11.2011Users and Citizens en pl 43 30.10.2011Adhocracy and Net4Change en pl 42 18.10.2011War on Fun en pl 41 16.10.2011Boli mnie w krzyżu pl 40 14.10.2011Technocomplacency en pl 39 10.10.2011I Can Haz? pl 37 09.10.2011Election Silence in Poland en pl 38 03.10.2011Kibice i kampania pl 36 02.10.2011E-textbooks, Johnny Mnemonic, business and the Net en pl 35 19.09.2011CC Global Streaming/Summit/Party pl 33 19.09.2011Czy jest coś takiego jak darmowe śniadanie? pl 34 12.09.2011Faktycznie Super pl 32 12.09.2011Diaspora-Based Comment System en 31 11.09.2011Conflict of values en pl 30 06.09.2011Wolność słowa to nie wolność od myślenia ani od krytyki pl 29 06.09.2011On-line privacy and anonymity: case in point en pl 28 04.09.2011On being careful with words en pl 27 03.09.2011W obronie QR Code pl 26 31.08.2011Stolica Nie Tak Święta pl 25 29.08.2011Of malware, hot steam, privacy, using one's brain and paedoparanoia en 24 29.08.2011Kragen Thinking Out Loud en pl 23 18.08.2011Ból, blizny, dziewczyny i wiosła pl 22 07.08.2011Worst. Woodstock. Ever! pl 21 27.07.2011Willpower, productivity and cycling en pl 20 19.07.2011Neo FreeRunner as a WiFi Soundcard en 19 10.07.2011A Weekend with lawyers en pl 18 09.07.2011One step closer to ideal en pl 17 04.07.2011Apostasy in Poland en pl 16 28.06.2011YAFR (Yet Another Facebook Rant) en pl 15 19.06.2011Wiara w priorytety pl 14 17.06.2011Important meetings, fun meetings en pl 13 13.06.2011Ooops I en pl 12 30.05.2011Playing with Node.js en pl 11 25.05.2011Mozilla, Google and the Location Bar en pl 10 24.05.2011At Sector 3.0 conf en pl 9 23.05.2011Layout, CSS and RSS/Atom en pl 8 15.05.2011Startup Weekend Network Fun Fun Fun en 7 11.05.2011Nowy szef Bramy pl 6 10.05.2011World's Smallest Open Source Violin en pl 5 10.05.2011Po kolejnym spotkaniu w KPRM pl 4 08.05.2011Inspiracja na niedzielę pl 3 08.05.2011I horizontally the whole blog is that serious pl 2 07.05.2011I can has brag en pl 1

Startup Weekend Network Fun Fun Fun

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To all the newcomers here — this is alpha version of my brag, and things will break. Please use Firefox or Chrome/Chromium to have the best experience; Opera will work too, but will not be as nice. Rekonq, Konqueror, other KHTML/Webkit-based browsers — newer version probably needed. To all the Internet Explorer and Safari users out there — please get a real browser, it's free and it's fun.

During the weekend I was responsible for the network and tech support at Startup Weekend Warsaw co-organized by my lab at Warsaw University of Technology. I cannot say I did a stellar job, but then again, I cannot say I didn't try and do my best to keep the network alive and kicking. So...

The Scenery

100+ participants. Every single one of them with at least one laptop. Most - with some mobile, WiFi-enabled device in their pockets, too. Many with some third device - tablet, second mobile, etc. All in all, probably more than 200 devices trying to connect to the Internet. Quite a bunch.

The Setup

2 Access Points (Linksys WRT-54GL; one with vanilla Linksys software, the other with DD-RT), two 8-port gigabit switches, loads of cable, and the Faculty infrastructure. And it's always about the infrastructure, ain't it.

The Plan

The Plan was simple enough and looked quite well:

  • set-up two different WiFi networks, on different, separated channels;
  • get as many people on the wired network as possible.
  • ???
  • PROFIT!!

As always, the "???" turned out to be the crux of the whole thing.

The Unexpected

As per Faculty Network Policy, many outgoing ports were blocked. Obviously, in that NAT-ed network, all the incoming ports were filtered. I decided to set-up a tunnel (an SSH-based VPN) for those few of our users that would need some "exotic" ports (like, oh you know, 25/tcp if they would fancy sending an e-mail). That was supposed to be far from mission-critical and just a courtesy towards the technically-inclined guys and gals in the room — so, basically, 90% of them.

However, it became uber-critical as soon as it turned out the (important) live audio/video stream that was supposed to allow more people to participate on-line actually uses some of the blocked ports. Whoopsie! The quick-and-dirty solution became a very important piece of duct-tape.

Fun with Streams

And there were loads people watching this stream too! Problem was, many of them were in the very room the stream was transmitted. Now, sending a video stream was enough of a network hog to cause minor hiccups; when people started watching it within the same network, basically all hell broke loose...

Oh, and let's not forget the great job Skype was doing to help our network tank even deeper. Yay for that.

The Fa(c)ulty Infrastructure

To be honest we had some real faith in the Faculty's solid backbone. And with good reasons too. It is a solid backbone, so why shouldn't we? Ah, faith, you are a funny thing. There comes a moment that reality catches up and, say, the Faculty's DHCP server goes down. Good for us we had a nice Ubuntu box (yes, the one with the SSH tunnel/VPN running). 5mins with apt-get and dnsmasq.conf and we were back on-track to the next failure in the string.

WiFi Mavericks

Well, obviously, the wireless quickly started getting quirky. As in, not working properly. Or at all for that matter. When suddenly 100 devices try to connect to a single AP in a matter of minutes, the AP will go down in a matter of those same minutes. Vicious circle.

So people started using 3G connections, which would not be that bad, as it would lessen the traffic on the poor battered APs, right? If only those were used via Bluetooth or USB. But guess what? Setting up your own ad-hoc WiFi mininetwork is sooo coool, right? Hence, suddenly, we had about 15 different ad-hoc networks interfering with the two Startup Weekend official WiFi nets. Guess what, that was not helping.

How it all played out?

or "putting the fires out"

To be honest - not well. There were simply too many points of failure. Too many fires. Often times the APs got in some strange mode in which connectios already established work passably, but no new devices were able to connect. Should we reboot such an AP to get the new devices on-line, or just go with the flow and let the already connected use the network without interruptions? Damned if you don't, damned if you do.

Lessons Learned

So, "mistakes have been made", moving on with the knowledge. In particular:

  • QoS! next time each and every single user will get a dedicated, albeit small, bandwidth channel.
  • less security can buy quite a nice amount of reliability; seriously, we did not need WPA here, we could have gone with WEP — or no security at all.
  • in-house as much as you can: get your own network segment, your own DHCP server, etc. — this way at least you are in control if something goes awry; and believe me, it will.

We got a few things right, a bit more on that further on down.

Blaming and Name-calling

We already know I was responsible for WiFi, but far from being able to do it all by myself. Special thanks for all the hard work go to Piorek and Karolina. Piorek was helping me all the time with tech stuff (and doing a great job); Karol was the bureau and chancellary, making everything go as smoothly as possible.

Many thanks to Kamila, Konrad and Krzysiek for the great atmosphere at the conference. You guys should have been pissed a few times, but weren't, and that went very far in helping us deal with the Wireless Notworking rather than interpersonal stuff. Seriously, to all the conference organizers out there — take heed, as this may well save your WiFi!

Last but not least - @zstanska and @mpaluchowski, doing the social media and video streaming, were usually the first to nag inform us about any problems. And in style! Also made fun of us on twitter. Really, you guys could have used a better service.

Finally, heartfelt thanks to all the people at and around Startup Warsaw.

Icing on the cake

Microsoft reps doing a presentation on a Linux box (that was our presentation box, simple as that)... I am not even sure they knew that, to be honest. Ah well, fun anyway. If and when I get the video, I will drop it here.

Actually, quite a few people had Linux on their lappys. Interesting times.

Follow Up

Today Shot sent a great article about making conference WiFi work. Better late then never — but hey, turned out we actually did many, many things right! I'll try writing a follow-up bragpost on that later, when I sleep a bit.