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reply to ISurfTooMuch
Re: And P2P users will ramp up their VPNs
said by ISurfTooMuch:VPNs are like using a router.
That's fine when everyone is providing their own connections, but now you have this huge VPN that has to route all those transfers, so it has to have enough bandwidth to do that. In fact, it'd need to have double the bandwidth of all the data flowing through it, since those bits are moving in and out at the same time.
Let's say that you only have one computer and it's connected directly to the modem. That modem can see the IP address of your computer, or any computer that you hook to it. Now let's say that you connect a router between the computer and the modem. Your modem can no longer see your computer's IP address, all it can see is the IP address of the router. Suppose your friend brings his laptop over and you let him connect to your WiFi. The modem has no idea that a different computer is using the connection, because it still only sees the IP address of the router. The router is hiding the IP addresses of the computers using it in the same way that a VPN service hides the IP addresses of the people who use it.
The major difference being that routers allow multiple computers to share a single IP address while VPNs assign a unique IP address to each user. However, the principle in the same.
Does your router need double the bandwidth for a single computer? No, it only needs as much bandwidth as is being used, up and down. VPNs also only need as much bandwidth as each user is using, up and down. For most people, the upload speed is a fraction of the download speed. I get 30mbps download, but only 5mbps upload.
I'll agree that to support BitTorrent transfers, the VPN will need a pretty good chunk of bandwidth, but using BT doesn't somehow magically double the bandwidth needed. Granted, other than when using file sharing software, most people don't upload and download at the same time, but it can be done. A person could start an upload to a service like Rapidshare and then download a file from somewhere else at the same time and use the same amount of bandwidth.
No, what I'm saying is that you'll need twice the bandwidth of what many people would assume you'd need to download a file of a given size. Say you have a 2 GB file. For a Web site or a single Bittorrent user to transfer that file in a given amount of time will take a given amount of bandwidth. However, the VPN will need twice the amount a user or Web site would need, since the file is essentially moving in and out of the VPN at two points: the uploading user and the downloading user. It'd be like transferring a large amount of data through the LAN side of a router. That data isn't just using one port; it's using two: the port of the sending computer and the port of the receiving computer.
My point here is that, in order to accommodate a large number of users downloading all these files, a VPN is going to need a very large amount of bandwidth, and it won't come cheap.