

Creating a Functional Network for a Radio Station? 60
E-bot & Ro-bert asks: "I volunteer for my campus radio station and, as the only techy there, I've been asked to help design their new network. We're on a very fixed budget and we're working with win98 PCs. The network needs to provide the ability to simultaneously stream and transfer large files (uncompressed WAV data) w/o interruptions to the stream. I know their current idea of using a simple hub and connecting all the computers won't work, but I'm drawing a blank on what to suggest. The specifics: Two of 6 Win98 PCs need to have the ability to broadcast audio data from any source on the network. The other 4 of 6 computers must be able to transfer files on the network w/o taking too much bandwidth away from the streams. I'm thinking of QoS, but how should it be implemented? What does the slashdot community look for, and suggest, in making a high-bandwidth network?"
Comment removed (Score:3, Insightful)
Re:win98??? (Score:2)
Re:win98??? (Score:1)
Re:win98??? (Score:2)
Re:win98??? (Score:3, Insightful)
Re:win98??? (Score:2)
Granted there were some restrictions, but getting a legit copy of Win2000 was about as hard as saying 'Please'.
Re:win98??? (Score:2)
M$ also gave some of the Engineering Honors students Win 2000 and VS 6.0, retail boxed versions of both, back in the day. So a Windows upgrade might not be so out of reach for them. But yeah I would move away from Win98, it really is
Re:win98??? (Score:2)
Uncompressed WAV data? (Score:5, Insightful)
The switch will allow you to dedicate 100 Mbps each way per machine by preventing each box from having to see streams in which it is uninterested. It will also allow you to run full-duplex, which will decrease latency if you're ACKing your transmissions (e.g. using TCP).
Really, a 10 Mbps switched network would probably be sufficient, but good luck finding a 10 Mbps switch these days.
I'd be more concerned about the ability of Win98 boxen to stream/process realtime data without hiccups, but I assume you've already got that solved.
pls think. thx. (Score:1, Troll)
I always suspected that whenver I've had trouble handling networked media files, that the problem really was that the network was just too bloody fast.
I'm so glad that NetLimiter will finally slow things down to such an extent that I can reliably transfer a WAV recording.
Too bad it's less than one-third the speed of my fucking cable modem.
Talk about pathetic and absurd. It's a stupid idea, and you know it. More bandwidth to the world than across the desk? Fucking-a NOT.
Now: How about spending $25 o
Re:pls think. thx. (Score:1, Funny)
He must be punished.
Re:pls think. thx. (Score:1)
Re:Uncompressed WAV data? (Score:1)
You could also use 1-mile category 5 cables wrapped around a gigantic magnet, this would efficiently limit the bandwith of every computer.
Seriously, how the hell this solution can be voted as "3, Informative"??? This is Slashdot, not Fox News!
Re:Uncompressed WAV data? (Score:1)
This guy is obviously that fuckwit that installs that 1 486 in the fucking cupboard thank RUNS FUCKING EVERYTHING but nobody knows what it does!
You know the box i'm talking about right? The first one you unplug and throw out..
Re:Uncompressed WAV data? (Score:2)
It certainly sounds more cost-effective than buying a high-end switch or router with rate shaping.
What you need is proper QoS on the switch (Score:2)
Why limit the speed of your machines on the network to a fraction of the available bandwidth, when in 99% of the time this bandwidth would be freely available to use and allow fast file transfers.
What you need to do, is implement simple and efficient QoS on the switch. If you know that two PC's will be streaming at 1.411 Mbps then define the appropriate class to isolate this type of traffic and reserve the appropriate bandwidth on the switch.
Then all the rest ca
Re:Uncompressed WAV data? (Score:2)
That's what came to my mind when I read the article. When transferring data @ 100Mb/sec in full-duplex mode the bottleneck typically becomes the hard drive. For that, you'd have to upgrade the RAM in the high-bandwidth using machines to max your disk cacheing.
Re:Uncompressed WAV data? (Score:1)
I have a 3com rackmount 10mbps managed switch with a 100mbps fiber port in the back.
$25 + Whatever it costs me to ship.
http://www.sharkchat.com/ [sharkchat.com] - you know where to get me
An Inexpensive and Flexible upgrade path (Score:3, Funny)
I have a suggestion...Upgrade the entire network to Macintosh 512's and PhoneNet and VOILA! Problem solved!
Use a switch (Score:1)
Start with the network (Score:3, Informative)
Make sure every PC has a 10/100 card in it.
At that point just test. I don't think that bandwidth is going to be the problem. I wouild be more worried about CPU since the machines are so old.
So just spend a little bit to upgrade the network and then start testing. Get some streams running first, then try to hammer the network with file transfers. See how much it takes to break things. You may find that the simple upgrade is all you need. If you can beef up the buffering on the destination for the streams it would help, but if you have to do that you're pushing the limits already.
Worst case:
2 network switches and 2 network cards each for the PCs. Do the file transfers on one network and the streaming on the other network. Segregating the traffic guarantees they will not interfere with each other on the network layer... I would make a "streams only" network and put all other office traffic, including the file transfers, on a normal office lan.
Hope this helps.
--Chris
Re:Start with the network (Score:3, Interesting)
Don't get a cheap taiwanese 10/100 switch. They don't really have more than 100 Mbps of switching capacity. Once two ports are communicating, all the other ports are being buffered. As soon as you have a higher bandwidth than about 5-10Mbps streaming conn
Re:Start with the network (Score:3, Insightful)
To actually be helpful, the parent is correct, a decent managed switch would be good. Actually being able to measure traffic will help to diagnose problems. In fact you might want to setup performance monitor on any existing PCs and duplicate the production traffic, just to see how much bandwidth you'll actua
Re:Start with the network (Score:2, Informative)
Curiously Netgear has 10/100 Mbps hubs [netgear.com] AND 10/100 Mbps switches [netgear.com]
Re:Start with the network (Score:3, Funny)
Nope.
Then again, they don't sell Windows 98 machines anymore either.
Comments from Similar Situation (Score:3, Informative)
I also work at a small radio station and a limited budget, where all of our computer are either Win98 or DOS, plus one Linux server. We've been streaming our audio onto the air from the Linux box using a Samba server no problem, just by using 100MB full-duplex switches.
The three problems that crop up are:
1) Large file downloads across the LAN, but this is only a problem when the files are being pulled to or from a computer that is serving or receiving a stream. This almost never happens where I work, though.
2) Hard drive accesses. This one isn't so obvious. Once or twice I've put a heavy load on the Linux box's drive (e.g. unthrottled data backups, recursive grep) and the drive couldn't keep up with both the backup and the audio file reads simultaneously.
3) Lack of contingency plans. If you're putting things on the air pulled from a computer across the network, you need to make sure your backups are thorough and extremely fast to restore. Our Linux server is backed up once a day (we only change about a dozen or less files per day) to a second hard drive, and we can pop a floppy in the disk drive and reboot to switch to the backup very quickly, all systems operational; then you have plenty of time to fix the problem and switch back to the main storage drive.
I hadn't heard of the bandwidth limiting software that someone else mentioned. It initially sounds like a good idea, but if you install it on the computers that are serving or receiving a stream, it would actually aggravate the problem, so implement that idea carefully.
So, let me get this straight (Score:3, Insightful)
I'm guessing the following:
The two PCs that "need to have the ability to broadcast audio data from any source on the network" have their audio hooked up to the broadcast equipment (maybe they're in the studio?).
So the requirement is that these PCs be able to access WAV files sitting on any old computer the station has lying around, without having to stage it on the broadcast PCs or on CD first.
You don't mention any special media software or anything, so I'm guessing when you say "Stream", you don't mean "deliver isochronous through the Internet or some other complex network, buffering and reassembling out of order bits, so that the data is played without skipping although possibly with considerable latency." You probably mean "click on a WAV file using Windows file sharing and have it play right away over our broadcast equipment without skipping."
It sounds to me like a Golden Hammer scenario. As resident computer geek, you feel it is your responsibility to deliver a technically whizz-bang solution. I'm guessing that what they really need, given their budget and technical sophistication, is some form of sneakernet: physical media and common sense operational procedures. People were running to the record library for call in request shows years before anybody had a computer network after all. And there are drawbacks in hooking up PCs that are connected to your radio to the machine the station volunteer uses to troll the Internet for pr0n.
Re:So, let me get this straight (Score:3, Insightful)
The first rule of asking for free technical help is do your homework. The second rule is to describe your problem precisely. The third rule is to have a thick skin.
If you do those three things, you can get your free advice. It's rather presumptious of you to expect to get professionally valuable advice if you don't do those things.
If you get off your high horse, you'll see I'm trying to be helpful here, which I have no obligation to do. Nor d
Re:So, let me get this straight (Score:1)
Okay, here's what I'd do. (Score:3, Insightful)
Since you're streaming, I assume you're streaming to the entire campus (and possibly the web, via the WAN link). Grab yourself a cheap Linksys 8-port gigabit switch. Don't cheap out and get a hub; get a switch. That'll take care of LAN bandwidth; don't worry about the WAN bandwidth (that's the university's problem).
Here's a link to that on Newegg (I don't know if you can claim tax-exempt, since you're a college organization):
http://www.newegg.com/Product/ProductList.asp?Man
Since these are Win98-era machines, I'm assuming they don't have anything other than regular PCI, so no PCI-E gigabit cards. You can get gigabit PCI NICs from Newegg pretty cheap - I see them for $12 and shipping here.
http://www.newegg.com/Product/ProductList.asp?Man
Next, we come to the real doozy, QoS implementation on the streaming machines. If your college supports it, grab a Win2K/Win2K3 Server license from them on the cheap and install Windows Media Components on it. That'll allow you to stream audio and video over the LAN/WAN. If not, try to dig up an OEM license.
2K/2K3 support QoS out of the box, so that issue is solved.
Depending on the amount of listeners you have, you may want to upgrade to another gigabit LAN drop sometime.
Anyone see anything I missed?
Re:Okay, here's what I'd do. (Score:1)
LTSP (Score:1)
No need to upgrade every machihe: make them ltsp-terminals!
Install one powerful server with Linux and the latest LTSP (LTSP 4.1 or maybe Ubuntu Breezy Badger). Wire everything with a 100Mb or 1GB managed switch (bandwidh control).
Think ahead. (Score:2)
not cheaply possible, probably... (Score:3, Informative)
I'm assuming you want two Windows 98 PCs to provide streaming audio to some arbitrary number of clients. Sending one stream isn't that hard... as others have said, that would be about 1.5megabits per stream. However, in ordinary TCP, you have to send a unique stream per client... even though it's the exact same data going to all clients. This adds up *fast*. So the number of clients you want to serve at any given time is the determining factor for how hard the problem is.
To give you an idea of the number ranges you're talking about, your network fabric is one potential bottleneck. Even on a 100Mb switch, you'll have a hard time exceeding about 60 connections. If you're willing to settle for MP3-compressed files (and LAME sounds REALLY good), you can cut your bandwidth needs to no more than 320k per client with almost no sound loss. 160k LAME still sounds very nice, and would probably let you support around 600 clients on a 100Mbit connection.
However, I doubt that Win98, even on a powerful machine, could stream that much data without croaking, particularly with the 600-connection scenario. It has trouble with multiple filesharing connections, a core function of the OS... running a heavy-duty server application on 98 is likely to be pretty troublesome.
What you really WANT is to be able to send the stream just once, and have all your clients tap into the stream and play the music. Multicast will do this... it is a one-to-many protocol. But your server, network infrastructure, and clients have to support it.
So what clients and server software do you use? I have no idea. I'd suggest starting with a search for 'multicast' on Freshmeat and going from there.
Overall, this is a hard problem. It's absolutely solvable, but it will take both expertise and money... the more of the former you have on tap, the less of the latter you'll need.
Even with the needed expertise, I don't think you can do this on the cheap. You're very, very likely to have to spend money. If they're talking about using HUBS, you're not even on the same page... this project, if it's meant as more than a toy for five people at a time, will most likely require a fairly expensive backbone.
Your campus IT department probably has both the expertise and the network backbone already in place, so your first stop should be them.
(I'm being interrupted, so I can't edit this as well as I'd like... hopefully any mistakes won't be too awful.)
Upgrade them PCs & 2 networks (Score:2)
As to the many replies about upgrading your machines, check wiht the college, local school board, county, etc. to see what happens to PCs that are replaced. The local community college sells a bunch each semester (4 year replacement cycle) to faculty/staff for $150, and then sells a f
I'll get slaughtered for this... (Score:2)
Re:I'll get slaughtered for this... (Score:1)
First Dump Windows (Score:2)
Install Linux (There are some great distro's out there on distrowatch.com that cater to music professionals).
Get a switch not a hub. Managed and one that could do vlan's if possible.
Traffic Policing (Score:2)
Bullshit Bingo (Score:1)
Re:Traffic Policing (Score:2)
Re:Traffic Policing (Score:1)
Besides, there's no reason you need gigabit for such a piddling task. If someone's going to be saturating a 100bt such that even a 1.4mbps stream is underbufferin
If you can, separate playout and office networks (Score:1)
If money permits, keep your audio network (with your playout machines and audio server on) separate from your office network (with office machines, printers etc). You can either use VLANs on a decent managed switch or better still have two completely separate networks connected by a machine / router to allow you to put audio on the server.
We had a vested interest in this because our audio servers were often running netware and w
How about a second subnet? (Score:1)
bandwidth (Score:1)
or even, use cables with only 4 wires in them so they autonegotiate a slower speed? (can be unreliable, in my experience).
Radio stream (Score:1)
Depending on how serious you are about it, you want RAID capabilities, as servers WILL crash, I assure you.
If you voice-track, then you need more sophistication,