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Why PyCon 2010's Conference Wi-Fi Didn't Melt Down

kdawson posted more than 4 years ago | from the five-point-two-is-where-it's-at dept.

Communications 145

jafo writes "There's been a lot of teeth gnashing going on recently about broken wireless at conferences. We just wrapped up PyCon 2010, with around 600 (out of 1,000) attendees simultaneously accessing the volunteer-run network, and response has been fairly positive. 2.4GHz (802.11b/g) continues to be problematic, but most users were on 5.2GHz (using 802.11n) and associating at 130mbps, with a 100mbps link to the net (though after the fact we found that 35mbps would have sufficed). My PyCon 2010 wrap-up reveals all the secrets of how we did it, including pretty bandwidth and user graphs."

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145 comments

Maybe nobody cared enough to have it melting?$ (0, Offtopic)

Adolf Hitroll (562418) | more than 4 years ago | (#31357330)

nt

Uhh (1)

robinstar1574 (1472559) | more than 4 years ago | (#31357332)

Why were you expecting it to melt down? The mere fact that it stayed up is a good thing. Why do you need to know the why? Was some idiot trying to melt it down? You should accept it as fact instead of questioning the why's.

Py Con? (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31357342)

what dat?

Re:Py Con? (0)

Anonymous Coward | more than 4 years ago | (#31358304)

I think that phrase is "WHO DAT?"

On units and their prefixes (2, Insightful)

Bromskloss (750445) | more than 4 years ago | (#31357350)

Editors, please do your job before you accept a story - that's an easy way to make Slashdot much better. In this particular story, it would have been easy - no research required. As I'm sure almost everyone here knows, m != M. Also, what is wrong with "b/s" instead of "bps"? (Also, how do I write non-ASCII characters here?)

Re:On units and their prefixes (4, Funny)

Jurily (900488) | more than 4 years ago | (#31357422)

(Also, how do I write non-ASCII characters here?)

What makes you think you can, huh? Just because url's can contain them and the civilized portion of the net is already fine with them?

Re:On units and their prefixes (0)

Anonymous Coward | more than 4 years ago | (#31360186)

Not a lot of people know this, but Slashdot is actually written in an undecyphered, obscure, probably guttural language from the previous millennia (a typical word of which is, in the author's original notation, "/(^\d{7}$)|(^\d{11}$)/") and anyone who could read, let alone meaningfully modify, the code must have surely long since perished.

Re:On units and their prefixes (-1, Troll)

Anonymous Coward | more than 4 years ago | (#31357446)

Editors, please do your job before you accept a story - that's an easy way to make Slashdot much better. In this particular story, it would have been easy - no research required. As I'm sure almost everyone here knows, m != M. Also, what is wrong with "b/s" instead of "bps"? (Also, how do I write non-ASCII characters here?)

I thought 130 millibits per second sounded kind of slow.

I want to illustrate "Offtopic" to that mod... (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31357506)

who modded the parent as "Offtopic"

Regardless of how much oil will drill for and even if every well is a gusher, the long term price trend for oil will be up. Even if supplies increase three fold, oil prices will continue to go up.

Now, the zipperheads on AM talk radio will say "drill here! drill now!" but the fact is the demand part is increasing dramatically because of Asia. We would need to find 10 Saudi Arabias (230 billion barrels of reserves) to keep prices stable of the long term - 20 -50 years. Ain't gonna happen. ANWAR has only 12 billion barrels of estimated reserves - the optimistic estimate. AM Radio jockeys have been talking out of their ass (as usual) in saying there's as much oil up there as Saudi Arabia.

That's offtopic.

Criticizing about units isn't - moron.

Re:I want to illustrate "Offtopic" to that mod... (0)

trapnest (1608791) | more than 4 years ago | (#31358298)

zipperhead is a racial term for some kind of Asian. Are you sure that's the term you ment to use?

Re:I want to illustrate "Offtopic" to that mod... (-1, Offtopic)

Dishevel (1105119) | more than 4 years ago | (#31358416)

The guy is an idiot who either dose not know or dose not care about basic market forces. All he needs to know is Government is Good. Companies are Bad and he is right.

Re:I want to illustrate "Offtopic" to that mod... (1, Informative)

Anonymous Coward | more than 4 years ago | (#31359236)

For fuck's sake, he was offtopic and rambling but you guys on the right need to stop lying about what people are saying.

He did not say government == good OR business == bad. You completely made that up, and used it as justification for calling the poster an idiot. Outside of politics, this sort of dishonesty is considered disgusting. But in the modern incarnation of the republican party, it's wholly encouraged.

You Glenn-Beck-listening assholes turn moderate health care regulation into a "government takeover". Anything that could even remotely be labelled progressive or liberal is instantly tarred as socialism. It sucks. You guys just don't care about reality anymore -- you just want everything to fit in your Ayn-Rand-inspired stereotypes.

Re:On units and their prefixes (-1)

Anonymous Coward | more than 4 years ago | (#31357618)

ý¥╜◘ ë ↓§F'ü○R°╞zu"c

Re:On units and their prefixes (1)

the_other_chewey (1119125) | more than 4 years ago | (#31357640)

Pet peeve of mine. Big one. It's really hard for me to take someone seriously who
writes about millibits while meaning megabits.

Re:On units and their prefixes (2, Informative)

maxwell demon (590494) | more than 4 years ago | (#31357682)

For some, like ä, ß, €, you can just use the HTML entities (ä, ß, €). More esoteric ones like ॐ just won't work.

Re:On units and their prefixes (0)

Anonymous Coward | more than 4 years ago | (#31357854)

For some, like ä, ß, €, you can just use the HTML entities (ä, ß, €). More esoteric ones like ॐ just won't work.

™ doesn't work either

high UIDs can't triforce (1)

Thud457 (234763) | more than 4 years ago | (#31358216)

&nbsp;&#x25B2;<br>
&#x25B2;&nbsp;&#x25B2;

Re:high UIDs can't triforce (1, Funny)

Anonymous Coward | more than 4 years ago | (#31358394)

awwww man, it "worked" on preview. Way to go, Taco. Ruined my fsck'n joke.

&nbsp;&#x25B2;<br>
&#x25B2;&nbsp;&#x25B2;

Re:high UIDs can't triforce (2, Funny)

iknowcss (937215) | more than 4 years ago | (#31359732)

Triforce fail

Re:On units and their prefixes (4, Insightful)

Rogerborg (306625) | more than 4 years ago | (#31357698)

Just FYI, the "job" of a Slashdot "editor" involves scoring Rob Malda some weed when you were at community college together, writing a very small shell script to post every 25th story submission, then scarfing beer and cheetos while playing in the Furry zone of Second Life for the rest of your "career".

Mod hints: -1 Troll, +1 Informative, +1 Insightful

Re:On units and their prefixes (1)

enilnomi (797821) | more than 4 years ago | (#31359486)

Meh; would have been funny except for the "community college" fail. (Especially since the reality [absoluteastronomy.com] of a wishfully elite church-affiliated [hope.edu] libarts school offers much better material ;-)

Re:On units and their prefixes (1, Funny)

Rogerborg (306625) | more than 4 years ago | (#31359616)

My Alma Mater was incorporated in 1410; anything founded after that is a Community College. :P

Re:On units and their prefixes (1)

Lordnerdzrool (884216) | more than 4 years ago | (#31357874)

Most books on computer networks that I have seen use bps. But I haven't seen many. I suppose the counter question would then be: What's wrong with "bps" instead of "b/s"?

Re:On units and their prefixes (4, Interesting)

TeknoHog (164938) | more than 4 years ago | (#31358234)

What's wrong with "bps" instead of "b/s"?

"Per" is a word that does not work in all languages, whereas "/" is a universal mathematical symbol. Even non-scientists use units like km/h, at least in Europe.

Re:On units and their prefixes (3, Insightful)

trapnest (1608791) | more than 4 years ago | (#31358328)

I suppose that would be really important if the summery were not in english.

Re:On units and their prefixes (1)

TeknoHog (164938) | more than 4 years ago | (#31358618)

Yeah, because scientists in different countries use different units and symbols... oh, wait

Re:On units and their prefixes (1)

TheLink (130905) | more than 4 years ago | (#31358622)

b (bits) and s (second) don't work in all languages either.

We spend lots of time complaining about people who confuse bps vs Bps, and milli with Mega, and there are the kibibyte vs kilobyte wars. And now b/s vs bps?

Re:On units and their prefixes (1)

TeknoHog (164938) | more than 4 years ago | (#31359110)

b (bits) and s (second) don't work in all languages either.

Not the full words, but the same abbreviations are used everywhere. I admit my original argument on "per" was a bit hazy in this sense. But these are mathematical quantities, so we can use mathematical symbols for clarity and brevity. Mathematically, "bps" looks like b times p times s, which is not intended.

For example, here in the Nordic countries, the words for "hour" begin with a "t", but we still use km/h to denote speed in kilometres per hour. The same unit is used all over the world and understood without ambiguities. Scientific collaboration is possible even when you're not particularly fluent in the same language, since most scientists use the same units with the same abbreviations.

We spend lots of time complaining about people who confuse bps vs Bps, and milli with Mega, and there are the kibibyte vs kilobyte wars. And now b/s vs bps?

What about bit vs. byte? The lowercase "b" sometimes means bytes, sometimes bits.

Re:On units and their prefixes (1)

Sir_Lewk (967686) | more than 4 years ago | (#31359302)

Mathematically, "bps" looks like b times p times s, which is not intended.

I guess it is a good thing that humans are good at deducing things from context then. Realistically, nobody familar enough with networking to even know what b/s means will be confused by bps. This is needless pedantry.

What about bit vs. byte? The lowercase "b" sometimes means bytes, sometimes bits.

Where does 'b' mean byte? I have never seen that in literature, and the only times I've seen it written in conversations it can generally be attributed to laziness, often accompanied by a lack of capitalization at all.

Re:On units and their prefixes (2, Insightful)

TeknoHog (164938) | more than 4 years ago | (#31359680)

Where does 'b' mean byte? I have never seen that in literature, and the only times I've seen it written in conversations it can generally be attributed to laziness, often accompanied by a lack of capitalization at all.

I once filed a bug about an application that used kb/s to denote kilobytes per second. It was changed to kB/s for a while, but pretty soon reverted to the lazy form. At least they used / though :)

Here's a nice example from the manpage of tc, part of iproute2:

Bandwidths or rates can be specified in:

kbps Kilobytes per second

mbps Megabytes per second

kbit Kilobits per second

mbit Megabits per second

bps or a bare number
Bytes per second

Amounts of data can be specified in:

kb or k
Kilobytes

mb or m
Megabytes

mbit Megabits

kbit Kilobits

b or a bare number
Bytes.

Well, perhaps this is so that you can write your command line in all lowercase. In other words, laziness.

Re:On units and their prefixes (1)

frogzilla (1229188) | more than 4 years ago | (#31359996)

Apparently it is in (at least) IEEE 1541. b is for bits, B is for bytes.

Re:On units and their prefixes (1)

TheLink (130905) | more than 4 years ago | (#31359382)

> For example, here in the Nordic countries, the words for "hour" begin with a "t", but we still use km/h to denote speed in kilometres per hour.

Over here the word for hour begins with j. But people understand both km/h and kph.

Lowercase b = bit. Uppercase B = byte.

Re:On units and their prefixes (1)

bdwebb (985489) | more than 4 years ago | (#31360370)

The formal term is bit/s rather than bps or b/s. The accepted informal abbreviations are bps and b/s. If anyone is in an IT related field and knows the difference between a 'bit' and a 'Byte', I guarantee you that they also know what the word 'per' means.

Re:On units and their prefixes (1)

TeknoHog (164938) | more than 4 years ago | (#31360558)

If anyone is in an IT related field and knows the difference between a 'bit' and a 'Byte', I guarantee you that they also know what the word 'per' means.

Agreed, perhaps this is only a matter of style. As a scientist I would never write something like mps for metres/second, even though the spoken unit is "metres per second". It would look silly and unprofessional, and I've already explained the point about mathematical symbols elsewhere in this thread.

Re:On units and their prefixes (1)

jadin (65295) | more than 4 years ago | (#31361046)

Is "per" even an English word originally? Looks like something we pillaged from Latin or wherever.

Re:On units and their prefixes (1)

frogzilla (1229188) | more than 4 years ago | (#31359226)

Thank you. I agree completely. Units are important and are not just letters to be applied willy-nilly. The m and M are not lower and upper case versions of a letter they are completely different symbols.

Re:On units and their prefixes (1)

bdwebb (985489) | more than 4 years ago | (#31360202)

FYI...just because the unit of measure is capitalized does not mean the data that the article contains is invalid. That's like saying 'Holy shit...I can't believe this article misspelled they're instead of their. I can't read this shit!' Granted, spelling and syntax issues are worth noting, but he clearly states mbps in his article and doing some deductive reasoning one can infer that the graph's numbers, being mentioned in the discussion, are related to the discussion. Also, he is not necessarily incorrect using M because mbps is frequently written as Mbps due to the fact that the standard format for the prefix 'Mega' in units is a capital M. This is the same for MBps excepting that the B is also capitalized here because it is 'Bytes' instead of 'bits'. Further, I don't quite understand what your problem with bps instead of b/s is. They are both the same thing and neither one is the real formal bit/s. You like to write it b/s, he likes to write it bps. I don't see that your 'issues' with this article have any merit and certainly neither of your 'issues' is serious enough to say 'OMG editor!! PLZ READ ARTICLES B4 ACCEPTING!!! How can you miss such glaring nonexistent flaws?!?!?!11!!?!@'

Re:On units and their prefixes (1)

FatdogHaiku (978357) | more than 4 years ago | (#31360274)

(Also, how do I write non-ASCII characters here?)

Only the printable ascii table and extended ascii table seem to be supported. If the HTML ascii code (e.g. é=&#233;) is greater than 255 (a.k.a. ÿ), then you can't get there from here. This fact has been pointed out by many users... no unicode, no change.

Re:On units and their prefixes (0)

Anonymous Coward | more than 4 years ago | (#31360834)

And isn't it supposed to be Mib/s now? Or does data transfer do the base ten thing? The whole thing is horribly confusing to me. (And certainly proves to me why we need to follow standards.)

Easy (0, Funny)

Anonymous Coward | more than 4 years ago | (#31357352)

They redirected all requests to goatse.

Typo in model number (3, Informative)

madsci1016 (1111233) | more than 4 years ago | (#31357360)

The AP he used was a Netgear WNDAP350. There was a typo in the article.

I avoid conference WiFi's... (4, Interesting)

SerpentMage (13390) | more than 4 years ago | (#31357488)

Because of the notorious slow conference WiFi's I have learned a new trick...

I use 3G networks. Since I live in Europe it would be expensive except I get pay-per-day for the country and that averages around 4 to 5 USD per day. That is great considering I can get 3G within restaurants, in my hotel room, and where ever else... Beats having to figure things out with the Wifi...

Re:I avoid conference WiFi's... (1)

Bromskloss (750445) | more than 4 years ago | (#31357554)

Since I live in Europe it would be expensive except I get pay-per-day for the country and that averages around 4 to 5 USD per day.

Does that mean you have a single SIM card (or rather, a UICC card, as I believe it's called) and use that in all countries or do you have to order a new one for every place you visit?

Re:I avoid conference WiFi's... (2, Insightful)

hitmark (640295) | more than 4 years ago | (#31357806)

probably picks up a pay-as-you-go at the airport of whatever nation he happens to visit.

Re:I avoid conference WiFi's... (0)

Anonymous Coward | more than 4 years ago | (#31358696)

I use a single prepaid Sim-card everywhere I go in Europe.

Re:I avoid conference WiFi's... (1)

Andy Dodd (701) | more than 4 years ago | (#31357660)

Elaborating on the previous user's question:

If you are using a different SIM for the "other country" provider, where do you typically start looking to shop?

If you are using your own SIM, if you were in a position like myself (US resident considering travel/vacation in Europe) - How would you go about getting a short-term SIM/finding one in your given country?

Every time I've looked into SIMs in other countries, the solutions I've found have been extremely expensive and despite Europe not doing the contract thing like we do, clearly not oriented towards the "used for 1-4 weeks" situation. Most of the short-term SIMs seem to be voice only too.

Re:I avoid conference WiFi's... (1)

Jaegs (645749) | more than 4 years ago | (#31358016)

This has been my experience too. I was in the Netherlands and was only able to get voice, not data, as I was not a resident (US citizen)--though I was going to be there for a month. I'm going there on Saturday and would love to have data whilst I travel around. If Germany is covered too, that would be great.

Re:I avoid conference WiFi's... (1)

obarthelemy (160321) | more than 4 years ago | (#31359768)

For France, here's what a quick search came up with:
- day pass @ 2 euros up to 10 megs, 8 euros then, for PC, need 3G dongle
- day pass @ 9 euros for mobile phone
- 15h pass @ 40 euros for mobile phone
from
http://www.sfr.fr/internet-mobile/offres-internet-mobile-cle-internet-3g/les-offres-internet-3g-?vue=00235e&addFilter=&usage=occasionnel&sfrintid=hbolmid_off_pass_bolmid [www.sfr.fr]
http://www.laboutique.bouyguestelecom.fr/forfaits-mobiles-offres-internet/forfaits-internet-mobile-3g-147_g.html#nogo [bouyguestelecom.fr]

I think the general idea is to plan ahead: find out what the big mobile phone operators are, go to their web sites, hope for an english version :-p Then once you get there, go to one of their shops, there's usually one at airports.

Re:I avoid conference WiFi's... (1)

cmoss (14324) | more than 4 years ago | (#31361352)

I start looking here: http://www.prepaidgsm.net/en/operators.html

It is a better resource for voice but you can find details on some data prepaid SIMs.

The last trip I took I was able to get a 3g data only SIM with 1gig data allowance good for a month for ~$20. This was Austria

More such reports, please! (4, Interesting)

Enleth (947766) | more than 4 years ago | (#31357496)

Even though it's just a short report, it's going to be very valuable for anyone doing similar work, be it for a conference or for a more permanent setup. No textbook is going to protect against those "oh crap, why didn't I think of it before?" moments like some actual experience would, and this posting is the next best thing after actually having someone with experience on site. And this works for any field of applied technology, not just wireless networking.

So, thanks and be back with some more soon!

Nothing to see here, move along (3, Informative)

Jurily (900488) | more than 4 years ago | (#31357518)

Re:Nothing to see here, move along (5, Informative)

Incongruity (70416) | more than 4 years ago | (#31357676)

Of course, the top answer to the question you link to comes from Sean (Jafo), the same person who authored the story submitted here. Sean's been nothing short of a hero @ PyCon for a number of years now – the one or two times we tried to replace him with a sub-contracted internet solution, it always ended painfully... or, well, more rightly, with Sean coming in and saving the day.

So, as someone who has worked with Sean on making PyCon happen, I can say, without a doubt, that he really knows how to get it done. My hat's off to him and Tummy.com

Re:Nothing to see here, move along (2, Insightful)

Anonymous Coward | more than 4 years ago | (#31358164)

If he's so great why did you try to replace him?

outsourcing is a fetish at harvard MBA school (1)

decora (1710862) | more than 4 years ago | (#31358254)

take a bunch of bluebloods who have maids and chauffers, their number one 'business' idea is of course 'dont do anything yourself, not even wipe your own ass. you are too important for that and shouldnt get involved in minor operational details. stick to your core competency'. then wait a few decades for the cancer to spread... despite numerous unmitigated disasters like Vietnam, Detroit, and the Iraq War.... congratulations! you destroyed America!

Re:Nothing to see here, move along (4, Informative)

AMK (3114) | more than 4 years ago | (#31360378)

For the first year or two, Sean was an unpaid volunteer, and the wireless was an all-volunteer effort. We felt bad about using up all his conference time, so we hired a company to run the network -- they're professionals, so everything should work fine, right? -- and Sean ended up helping them diagnose problems, using up *even more* of his conference time. Now we just pay Sean.

i feel his pain (0)

Anonymous Coward | more than 4 years ago | (#31357666)

[quote]This was caused by us doing our own RJ47 crimping, which I really wanted to avoid.[/quote]

I really like to avoid doing RJ47 crimping, myself. Results are always totally unexpected.

Re:i feel his pain (2, Insightful)

v1 (525388) | more than 4 years ago | (#31357838)

Saves the worry, AND saves the fingers. Mine start cramping at about the 25th end when I'm in a hurry.

I can't believe that they seriously planned to crimp things by hand. I can understand for the occasional single long haul runs, but they made it sound like they were doing many dozens of crimps, and that's just plain silly. The money you save in not paying for molded cables you lose in time and hassle created by bad crimps.

Did you catch the other hilarious minor detail? they only had one crimping tool! That's how to turn fail into epic fail. And they PLANNED it this way... wow.

Re:i feel his pain (1)

gmack (197796) | more than 4 years ago | (#31358190)

For single long haul runs you are better off with a 110 tool and a proper female end. It's easier, faster, and more reliable.

I don't own a crimping tool on principal.

Re:i feel his pain (1)

v1 (525388) | more than 4 years ago | (#31358708)

I don't own a crimping tool on principal.

Know what's more fun? I know two people that own a crimping tool and are color blind. lol... "Does this look ok to you?". *shakes head* "cuss* *cuss* *snip*. *grumble* *grumble*

And the other tech here is also color blind. There sure is a lot of that going around...

Re:i feel his pain (1)

RobertLTux (260313) | more than 4 years ago | (#31360644)

and why didn't they just pop down to the local RadioShack and buy a few crimpers??

IETF meetings solved this 2 years ago (4, Informative)

mbone (558574) | more than 4 years ago | (#31357674)

IETF meetings are larger (1200+ typically), and basically everyone has an uses a laptop / pda, so they make for a demanding wireless environment [ietf.org] . After some really bad experiences, resources were put into this, and the last few years, things have really improved.

What we have found is that

- it is necessary to have good gear (not all access points are created equal)
- To serve a lot of people, lower the power per access point, and put in a lot of them. Raising the power because of poor reception is a mistake.
- having both 2 GHz and 5 GHz networks really helps.
- telling attendees how to turn off "ad hoc" mode on their computers really helps.
- tracking down ill-configured boxes doing bad things on the network really helps.

Having said that, most recent IETF meeting sponsors have chosen to pay for professional wireless network providers. This is not trivial, and there is no better way to cause a flame war than to have the WLAN melt down.

Re:IETF meetings solved this 2 years ago (1)

Anubis350 (772791) | more than 4 years ago | (#31357894)

While it certainly doesnt apply to a smaller, less vendor-sponsored conference like pycon, Supercomputing's SCinet [supercomputing.org] is always a rather impressive feat. The wireless reception off the main conference floor this past year sucked on 2.4 (I dont know if it was the fault of the convention center's construction plus maybe policies that limited router placement or something), but if you had a device that could do 5 (like most people at the conference), you were golden. Speeds were quite good too, and SCinet handles a *lot* of traffic.

Re:IETF meetings solved this 2 years ago (1)

Omnifarious (11933) | more than 4 years ago | (#31358370)

Is there a good place that lists which equipment is good and which isn't?

Re:IETF meetings solved this 2 years ago (2, Interesting)

mi (197448) | more than 4 years ago | (#31358412)

IETF meetings are larger (1200+ typically), and basically everyone has an uses a laptop / pda, so they make for a demanding wireless environment. After some really bad experiences, resources were put into this [emphasis mine -mi], and the last few years, things have really improved.

At what point does it become cheaper (or comparable) to just run a CAT6 cable to every seat in the conference room? I mean, movie theaters and airplanes have that for headphones. Every laptop I've seen has an Ethernet jack... You spend some more money once, but then save on every event... And you provide better service — while emitting less radiation and consuming less electricity (would somebody think of the polar bears?!)...

Those few devices, that only have WiFi can still use wireless, but, if the bulk of your audience use cables, you can get away with cheap "SoHo" equipment...

When renovating my house, I ran CAT6 to every room — the number of power outlets is only 4 times higher, than :-)

Re:IETF meetings solved this 2 years ago (1)

Zerth (26112) | more than 4 years ago | (#31361204)

Now if the facility manager thought to do this the next time they redo the carpeting, that'd be awesome for tech conferences.

But I think having a grid of floor boxes dense enough would make the floor rough to walk on when arranged as a vendor hall or dining room.

"/." meetings solved this 2 years ago (0)

Anonymous Coward | more than 4 years ago | (#31360418)

A good choice for AP is this [amazon.com]

The real trick was getting APs that would do 802.11n on both radios at the same time. Most APs are not able to do N on both radios. So we ended up using the Netgear DWNAP-350, a $300 AP but it does support lots of features including gigabit Ethernet, N on both frequencies at the same time, PoE...

The Netgear WNDR3700 can't?

Piffle. (2, Interesting)

dtmos (447842) | more than 4 years ago | (#31357692)

The bimonthly IEEE 802.11 standards meetings are co-located with other 802 wireless working groups (802.15, 16, et al.) and regularly have attendance from 600-1000 persons, substantially all of whom are active on 2.4GHz (802.11b/g) substantially all the time the meetings are in session (it's required to register session attendance, upload and download documents, etc., but is largely used for Internet-based multitasking). These networks have worked flawlessly for years. They are specially-built for the meetings by VeriLAN Event Services [verilan.com] , a company specializing in network services for special events. Their web site claims that they have supported events with up to 5000 simultaneous users.

Re:Piffle. (2, Funny)

mbone (558574) | more than 4 years ago | (#31358422)

Verilan and Swisscom are the IETF's providers at the present, for when the sponsor doesn't want to do it themselves.

When sponsors do do it themselves (generally because they sell wireless gear) I would advise them to be afraid. I still remember a poor sales-engineer from a previous meeting (that did not go well in a wireless sense) being told they had implemented some piece of the standard wrong, by engineers who had helped to write the standard. After a few rounds of that, he started visibly flinching whenever someone else came up to complain.

Hmm, other equipment options? (2, Interesting)

Andy Dodd (701) | more than 4 years ago | (#31357708)

I don't like the dual-band routers much - they always seem to do a crap job serving both bands, even in the rare cases that the router supports it.

$300 each for those Netgear APs sounds ridiculous when you can get carrier-grade equipment (such as Ubiqiti Rocket series units) for far less. Instead of getting dual-band stuff, just set up independent 2.4 GHz and 5 GHz networks.

Re:Hmm, other equipment options? (1)

G00F (241765) | more than 4 years ago | (#31360638)

I found it interesting that they used netgear products as well. I use to use a lot of netgear, however, the stuff I have used in the last 5 years have been complete and utter crap. Dieing in a year, and the replacements dieing in a year as well. Although, they do have a nice list of supports xyz technologies.

I know their office grade is different than their home/soho stuff but my home network which was built 2-3 years ago had 6 different netgear products now only has 1, replacing them with Dlink. In fact I am replacing a 8 port gig switch, and may be using the Trendnet because of the lower power it has over even all the other lower power.(and cheap)

A few other things... (1)

Andy Dodd (701) | more than 4 years ago | (#31360810)

GAH. Somehow I typed this all up but forgot to hit submit...

My experience is that in addition to few routers/APs doing simultaneous dual-band, many don't allow you to do different modes on the two bands.
802.11n degrades severely in the presence of legacy devices, and it's a spectrum hog. So N in the 2.4 GHz band is a bad idea - my experience is that every 2.4 GHz N solution I've worked with has performed worse than a good 802.11g router with an external antenna.
802.11n works pretty well in the 5 GHz band - very few legacy devices and plenty of spectrum.

Nearly all dual-band routers/APs also now use internal antennas. Routers/APs with internal antennas suck. Period. It is far easier to find singleband routers that support external antennas (and singleband antennas) than dualband routers that support external antennas.

My own apartment setup is:
802.11g router with sector antenna running DD-WRT
802.11n router configured as an AP in the 5 GHz band, running "n-only" mode
Each network has a slightly different SSID so I can explicitly choose which network to use.

I would reccommend something like:
1) A 2.4 GHz network of G-only units with external antennas like the Ubiqiti Bullet2 or Bullet2-HP
2) A 5 GHz network of N-only units with external antennas

Very few people have equipment capable of 802.11a but not 5 GHz N, and forcing N-only on the 5 GHz network will improve performance. If you really want support for "legacy A" users, install a third network on a different set of channels.

Test, you idiot (2, Insightful)

cerberusss (660701) | more than 4 years ago | (#31357718)

FTFA:

Crimping your own RJ45 should be avoided

Author should have said "testing should NOT be avoided".

I hate it when people say such things. A cable tester costs $15 and you neglected testing. Don't say "crimping your own RJ45 should be avoided". That's blaming someone else for your idiocy.

Re:Test, you idiot (2, Insightful)

ZorinLynx (31751) | more than 4 years ago | (#31357900)

As someone who crimps our own cables at work, full agreement here.

I rarely have problems with self-crimped cables. Another group that crimped its own cables here was having all sorts of problems. Why? They were doing a lousy job of it.

Test every cable. Make sure the conductor order is correct. Make sure the conductors go all the way into the connector to the stop at the end. USE THE RIGHT CRIMPER. Some cheap crimpers don't crimp all the crimp points and leave the wires less mechanically supported. The crimp point that's usually missed is the one just behind the metal contacts, which is one of the most critical points of all.

And most importantly, make sure you are using the correct plug ends for the cable you are using! Stranded and solid conductor cables require different types of plug. Using the wrong one nets you a connection that works now but won't work later.

Re:Test, you idiot (0)

Anonymous Coward | more than 4 years ago | (#31358442)

Problems with self-crimped cables -- you should really test with a qualification or certification tester rather than some LED box -- you want to make sure there are no crosstalk, impedance or resistance issues. These may work well if you just have the patch cord, but when it's at the end of a 90 meter run, they start to matter. For example, split pairs would never show up with continuity testing, but on a even slightly longer patch cord they'll kill your gigabit and even fast Ethernet. Those testers unfortunately cost hundreds if not thousands of dollars.
Also, factory-made patch cords have other nice things such as strain relief / anti-tangle boots and mechanical strength against flexing at the connector and pull forces. At two dollars per patch cord for a tested Cat 6 cord we've long since given up making them ourself.

Re:Test, you idiot (1)

v1 (525388) | more than 4 years ago | (#31357924)

The other thing I was wondering about is the use of stranded or non stranded cat5, and the associated ends you need to use. Last major crimping I had to do, I was provided with solid core cat5 and ends for stranded. (with spades in the ends) You can imagine how that goes, makes for incredibly unreliable crimps trying to use stranded ends on a solid cable. (I don't expect vice-versa to be much better)

Have they settled on a standard yet? Solid I hope. It's been a few yrs for me.

Re:Test, you idiot (2, Informative)

Kizeh (71312) | more than 4 years ago | (#31358396)

Solid is for horizontal runs (within walls), stranded is for patch cords that will be flexed, such as between a jack and a user's computer. As it's always been.

Re:Test, you idiot (1)

v1 (525388) | more than 4 years ago | (#31358678)

As it's always been.

Perhaps. But I have yet to work for a place that stocks both kinds of cables and ends.

I doubt the flex properties of stranded has much of a net benefit for use in a patch panel... the RJ45 ends are going to wear out long before solid cable. And I've never seen solid get kinked in a patch panel. (contrary to seeing numerous examples of a long run getting kinked)

Re:Test, you idiot (0)

Anonymous Coward | more than 4 years ago | (#31359820)

As it's always been.

Perhaps. But I have yet to work for a place that stocks both kinds of cables and ends.

I doubt the flex properties of stranded has much of a net benefit for use in a patch panel... the RJ45 ends are going to wear out long before solid cable. And I've never seen solid get kinked in a patch panel. (contrary to seeing numerous examples of a long run getting kinked)

You've probably never SEEN a solid core patch cable, because nobody makes them (unless you make them yourself), patch cords are ALWAYS stranded. If you picked up a solid core patch cable, you'd immediately say "what is wrong with this" because it's stiff as a ruler.

Re:Test, you idiot (1)

Kizeh (71312) | more than 4 years ago | (#31360294)

Well, not necessarily in a patch panel, but on the office side where the cable gets moved on a daily basis, kicked around etc. We've certainly seen solid conductors snap after enough flexing. (Then again, when you roll chairs and filing cabinets over patch cords, they all get demolished sooner or later ;-) )

My employer did stock both, when we still did patch cables in house.

RTFA, you idiot (0)

Anonymous Coward | more than 4 years ago | (#31358360)

RTFA.
If your read further, he said that the issue wasn't the WIRE connection, it was the little plastic snaps that lock the ends into the jack.

"the crimp on ends had the tabs in fairly close, so unless you bent them up before plugging them in, they wouldn't click in place."
"Because of this, we had several of the Ethernet connections come loose"

He said he'd avoid it because:
1) it's harder to get the good quality control (both physical crimp, individual part quality & total assembly), especially with Volunteers like he had.
2) It takes a LOT of time. He also noted that they didn't have enough crimpers to have multiple people crimping.

With pre-terminated cables with strain relief, you hopefully avoid both those issues, at the addition of a little cost.
I sort of agree with him: preterminated cables would save lots of time, and avoid having to buy multiple crimping tools & a tester to get a minimal speed/quality boost.

Re:Test, you idiot (1)

TheLink (130905) | more than 4 years ago | (#31358840)

In most cases it's better to buy pre-crimped certified cables and test them, than to crimp them and test them.

How much money are you going to save? If you're charging $$$ for the project, crimping your own cables is a waste of time and resources. Unless of course your job is making cables :).

Re:Test, you idiot (1)

Vancorps (746090) | more than 4 years ago | (#31359544)

Except in temporary setups where you don't have specified lengths or you have lots of wildly different lengths. By the time you measure out a run and test a pre-crimped cable you could have already installed the uncrimped cable. This also doesn't mention the fact that pulling cables with ends already on them is quite difficult compared to just straight cat5 or cat6 especially if you're using conduit.

We used to do the whole pre-crimped thing, costs us a lot less money and we can deploy a lot faster just making new cables. We deploy a good 50 miles of cabling for each of our events, that includes fiber as well as cat5. Fiber runs require more care so they still make sense to buy pre-made especially considering that they are more expensive per foot. We buy sufficient strand count fiber so it doesn't take long to string usually since you only have to string one, then copper takes whatever is in range.

Naturally everyone in my department has a set of professional grade crimpers though and a couple black box testing kits. We can setup our entire office consisting of 60 machines in one day with four of us. That used to take us three days having to measure out cables to make sure the run would work because naturally somebody decided to move something so it no longer matches our nice CAD drawings. Now we just simply don't have any issues.

Most of the time we don't even bother to test our cabling because we know how to crimp properly, all of us, so I just plug my netbook into each station and verify its connected to the right VLAN and away we go. I haven't had one not work in years unless wind has thrown a tree against it or something, but of course we still test because that's the last thing you want is for some marketing drone to come in and immediately start complaining they can't connect.

Most people don't realize the harsh realities of temporary setups that hold thousands or in my case tens of thousands of people many of whom love to hop on the network whether to watch our video feed or to surf the net. Course I don't know how many events PyCon has, I have four events that stay up for three to six weeks at a time. Our stuff just works and has survived impressive weather conditions since lots of it is in tents. We owe this to redundant wiring and switching. We've done the math as well and it's not even worth it to retain the cable, you might as well throw in a bin and recycle and use the money to fun an office party.

Crimping?! WTF? (-1, Flamebait)

cepler (21753) | more than 4 years ago | (#31357938)

I lost any possible respect for the poster when I saw this:

Lessons Learned

                * Crimping your own RJ45 should be avoided.

Any idiot that's been in IT and networking knows you don't crimp your own connectors. You punch down wire to panels, you buy pre-made patch cables.. Often people will purchase the wrong crimp connectors for the cable they are using, or they will use solid wire for patch applications AND use the wrong crimp connectors (solid vs. stranded) and then wonder why things don't hold up... *rolls eyes*

Re:Crimping?! WTF? (1)

ZorinLynx (31751) | more than 4 years ago | (#31357964)

Any "idiot" that's been in IT and networking knows HOW to crimp their own connectors properly so that they work reliably.

If you can't trust your people to do the job correctly, then yes you may be forced to buy pre-made patch cords. This doesn't mean there's something inherently wrong with doing your own crimping; you just have to do it properly.

stating the obvious (1)

malp (108885) | more than 4 years ago | (#31358222)

There's a certain type of person who thinks that simple statements of truth are either wrong, stupid, or unnecessary. These people had a field day ridiculing Newton when he presented his 3 laws of motion.

Learning is knowledge (1)

adosch (1397357) | more than 4 years ago | (#31357944)

...So you pretty much learned:
  • Not to be a novice and get your enterprise and common-sense hat on for a big event?
  • How to a proper WIFI site survery prior to deployment?
  • Not to make your own hacked-together setup (This isn't your mom's basement, buy/use legitimate, reputable and trusted equipment, cabling, software, ect.
  • Using SOHO/home networking equipment for THAT many potential users?

Learning is good and you were successful for the most part. Regardless of the downplay of comments you'll receive here on /. on what you did, it's what you took away from it and how to make it better for next year is what will make you great. That's how we all learn is by things like this. Anyone to admit otherwise is a more than likely a liar.

Re:Learning is knowledge (2, Insightful)

RzUpAnmsCwrds (262647) | more than 4 years ago | (#31360700)

Actually knowing a bit about jafo and the setup at PyCon, I can tell you exactly what's wrong with your idea: money.

The IEEE/ACM SuperComputing trade show's network (SCinet) does exactly what you say. They also have 10,000 attendees, over 50 people working on the network, a decent budget, and a ton of donated gear and bandwidth.

PyCon (and jafo) don't have $100k to spend on the network. That means that you have to make do with low-cost commodity hardware. The fact that the network can stay up and deliver acceptable quality of service is a testament to jafo's experience.

Building a conference wireless network that works when you buy gear designed for that purpose isn't particularly notable.
Building a conference wireless network that fails miserably with consumer-level gear isn't particularly notable.

Building a conference wireless network that works with consumer-level gear on a shoestring budget *is* notable.

The tummy people are great (1)

mmcgrath (1072410) | more than 4 years ago | (#31357968)

Tummy sponsors some hosts for the Fedora Project (I'm a Fedora contributor) and they're just all around good people. If you're looking for hosting give them a serious consideration: http://tummy.com/ [tummy.com]

Typo in the Summary (0)

Anonymous Coward | more than 4 years ago | (#31358010)

"but most users were on 5.2GHz (using 802.11n) and associating at 130mbps". It should say 802.11a, not 802.11n.

Re:Typo in the Summary (1)

makomk (752139) | more than 4 years ago | (#31358492)

Nope, they really do seem to mean 802.11n and not 802.11a. Recall that 802.11n includes both 2.4GHz and 5GHz networking...

Damn toasters.... (2, Funny)

fractalboy (1078025) | more than 4 years ago | (#31358120)

Hmmm.... that's odd.... the Cylons must have managed to just miss all of Picon's wireless access points with their barrage of nukes. Or maybe it was just part of their "plan" all along?

PPTP? Seriously? (1)

QuoteMstr (55051) | more than 4 years ago | (#31358178)

one of the guys couldn't establish a PPTP connection

PPTP? People should know better. PPTP is very [schneier.com] weak [wikipedia.org] . OpenVPN and IPSec are much better all around.

This year I tried to get public IPs again... (1)

Omnifarious (11933) | more than 4 years ago | (#31358204)

This year I tried to get public IPs again, but we just weren't able to get any meaningful number of them. So, we had to do NAT. This worked well, and I had no complaints beyond the first one: one of the guys couldn't establish a PPTP connection. I had forgotten to load the NAT protocol modules... I loaded those up and it went smoothly after that.

And you think that's going to be more likely to happen in future years?!

Next time, set up IPv6. Use 6to4 tunneling if you can't get an actual IPv6 drop from the network provider. But just get IPv6. Then everybody will have a public IP.

Re:This year I tried to get public IPs again... (1)

Vancorps (746090) | more than 4 years ago | (#31359668)

Except that more than likely the vast majority of attendees won't have IPv6 enabled on their machines or are running XP or older. IPv6 in XP is crap especially if you're trying to do a 6to4 setup.

The problem with conferences is that you have to accommodate a wide range of equipment. I'd love to just deploy 802.11n at my events except that I've yet to see any vendors or attendees with equipment that supports it. Hell, for a lot of them 802.11b is still the only choice. So I'm left with needing to expand 802.11b/g while at the same time deploying n so that the people paying for wireless can indeed get it reliably. That's why I only offer where I know I can do it properly otherwise we run them a wire for free. Haven't had to do that in a long time as I've made all those rookie mistakes before and I learned from them.

If you make your audience adjust to you expect lots of complaints and refunds!

Re:This year I tried to get public IPs again... (0)

Anonymous Coward | more than 4 years ago | (#31361050)

Yeah. I was there, and I guarantee you--I don't run IPv6. And I will resist it as long as I can, because it's a broken piece of crap in every implementation so far. DNS munges it all the time, libc dns lookups handles it inconsistently with ipv4 and treats * records differently--resolving a * record in ipv6 before looking up the appropriate A record in ipv4 for a domain for example. There's been other known bugs with the implementations for nearly six years that nobody's fixed, and yet we still have people screaming to use it.

And I don't feel like customizing my laptop's firewall rules to do anything other than reject ipv6 so I don't have to deal with this or troubleshoot it. Hell--what was the last remote exploit in oBSD? Oh yeah... ipv6.

Now, I don't expect jaf0 to support ludditism for the sake of as much. But public IPs are actually invaluable in these spaces--people throw up a django install on their system and have it shown to their peers all over the net in a few minutes. Heck--in order to preserve bandwidth last year I'd pulled down a VM over my 3g aircard and then served it internally. I didn't *need* a public IP for that, but this is a conference where probably 75% of the attendants are capable of throwing up a webserver in under five minutes with a few lines of code. And it won't be Apache.

IPV6 just wouldn't meet the needs.

Re:This year I tried to get public IPs again... (1)

david_thornley (598059) | more than 4 years ago | (#31361072)

The network was set up with low-end gear and a lot of ingenuity to save money. I don't have a whole lot of experience here, but I haven't had a low-end router yet that understood IPv6. I'd really like that to change, but I think it's going to be a few years.

This is nothing!!!!! (1)

Shadow_139 (707786) | more than 4 years ago | (#31358896)

This is nothing, have a look at the setup at 26c3 last year.... Full 802.11a/b/g/n, DEC and GSM !!!!!!

two questions (1)

eison (56778) | more than 4 years ago | (#31359204)

* My laptop only does 2.4ghz n, and I thought that was par for the course? Are laptops with 5ghz N really that common?
* There is clearly a quality difference among access points, but how do you tell in advance which equipment will work and which won't?

anyone know FOSDEM's setup? (1)

AceJohnny (253840) | more than 4 years ago | (#31359314)

This year's FOSDEM [fosdem.org] in Bruxelles had over 2400 unique MAC addresses and 3600 visitors a day(source [twitter.com] ). We enjoyed a 1Gbps pipe, and far from saturated [twitter.com] it.

It was overall of excellent quality, though there was a glitch in at least one of the hacker rooms where the operators had to upgrade the AP firmware. The geographic setup was more broken out: FOSDEM happens at the Universite Libre de Belgique (how appropriate), with talks in lots of classrooms spread across a few buildings.

It would be useful for everyone if they could post a writeup of their infrastructure.

Not melting is such a relative term (1)

Ranger (1783) | more than 4 years ago | (#31360804)

I wouldn't exactly call PyCon's Wi-Fi a success, but it was better than in years past. The venue changes every two years, so all the bugs have to get worked out in each new location then it's better the second year. I mostly used my iPhone on 3G and stayed off of Wi-Fi. The Hyatt must have had a micro-cell in the bldg because I had a strong signal 2 floors below street level.

If you tried to use wi-fi during the keynote session in the morning, it was slow as molasses. During the regular conference sessions it was more reasonable.

During Guido's opening talk he took questions via the twitter feed. That could have been painfully slow but it wasn't. It's not that twitter takes up much bandwidth, but the website serving up the feed and everyone hitting it could have been.
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