For publishers, engineers and anyone else who needs to send very large files (100MB to 1GB-plus) over the Internet, performance and reliability can be big problems. After all, no one wants to wait a couple of hours downloading a large file and then have to start all over again if something goes wrong two-thirds of the way through.
An answer to this problem, (although not "the" answer) is Gigabyte Express 5 from Niwot Networks. Although Niwot pitches it as a peer-to-peer product, the $795 Gigabyte Express is more accurately a point-to-point product, letting a business connect to clients over the Internet for managing large file downloads. The client can use standard TCP/IP, but it also uses an extension to TCP/IP for increased download reliability.
In tests, Gigabyte Express did a good job of seamlessly recovering from interrupted packets. Performance improvements (or lack thereof) may vary based on the situation. On a standard Internet connection between clients in Colorado and Massachusetts, Gigabyte Express was actually slower than an FTP connection. However, I got improved speed on a cable modem, and Niwot positions the product to businesses with international clients.
Clients are required at both ends, so the product is relatively secure, but it still needs some kind of authentication option. Also, it runs only on Windows systems.
More information is available at www.gigabytex.com.