them had to download them in their entirety and save them to their disk. Lately however I’ve been using MPEG’s played off the RealPlayer, and I’m trying to understand the difference.
Please bear with the way I form these questions. I am a cartoonist, not a techie.
(1) Does the animaton run on a constant stream off the server?
I’m imagining the server as a box of Cap’n Crunch, when I play a file is it as though the Cap’n Crunch is poured into my left hand (which is my computers RAM) in a big stream, then my right hand (which is the RealPlayer) picks individual crunchberries out one by one.
Or, is the RealPlayer picking out the crunchberries one by one directly out of the box?
Or, does the whole box have to be dumped into my left hand (the RAM one) before the right hand can get at 'em?
(2) Does the “streaming” aspect esentially hijack the hard disk of the server it’s playing off of? Preventing it from serving anybody else who’s page is on that disk?
I’ve been stashing these animations on skunked Geocities and Angelfire sites (dummy index pages with the animations stashed among the files) and just hyperlinking from my real site. Is this esentially preventing the server from serving anybody else who’s page is on that disk?
Thanks
Inky
As I understand “streaming” technology to work, and this is a WAG, but not completely unfounded, is as follows:
To play a bit of information, the computer receiving it must think it is receiving a file. Now, that file does not have to be an actual file on a hard drive somewhere (though it can be), so long as the sending computer says “here’s a file, start playing it” the receiver says “OK” and does as though it were reading a file off of its own harddrive. To stream live video, all the sender has to do is send it as though it were a “file” even if its a never ending stream of data.
Though again, someone with a real understanding of this should answer, because this is mostly a WAG on my part…
As for #1 your first guess is closest.
Streaming video and/or audio is a bit of a fudge. You aren’t really getting the stuff quite realtime. You may notice when you start Real Player and run a file it starts buffering the file. In essence it is grabbing the first pieces off of the server and storing them in the buffer (basically memory). After a bit your player starts moving. If all goes well the head start given your computer will allow the media stream to play smoothly. Your computer is now both playing and downloading at the same time. Even if the download stalls for a short time the buffer will take care of smoothing things out (i.e. the data is already there). If the download slows down too much or stops the player can catch up to the end of the data and it will stall till it gets more to play. The buffer usually only buys you several seconds.
As for #2 the answer is no…it does not hijack the server. While a computer can do only one thing at a time it does them quickly. Multitasking (running several programs at once) is really a very fancy juggling act the computer does in the background but it does it all fast enough that it appears to us as if it is doing many things at once. When it comes to retreiving files even modest servers can access data off of their harddrives much faster than individuals accessing that machine can accept the data (even over Local Area Network speeds which are generally much faster than most connections to the internet). The server starts a round-robin on the users requesting data.
It is possible to overload a server with requests. First it will slow down…take longer for you to retreive a file. Eventually you may get nothing when it gets really busy. When you request something from a server it sends a quick message back to your pc saying “I got the request”. If your pc doesn’t see that it will try a few more times. If it still doesn’t get a confirmation your program will timeout (you’ve probably seen this on occasion when surfing the web). Usually if you try again a short time later you can access what you’re looking for. You rarely see this on a corporate LAN because any IT person worth their salt will make sure to build their systems to handle the know number of users and their general traffic load.