US Patent 7558842 Large file transfer in a design collaboration environment

Systems and methods for use in a B2B communication or integration environment, operating using a web browser to access systems protected by an enterprise network firewall, to transfer files in a manner that is reliable, restartable, and secure. After assuring the transfer is allowed, a web browser sends a signed applet to a file transfer client, which makes an out-of-band connection to a file transfer server. The file transfer client and file transfer server interact using a bi-directional protocol suited to file transfer operations. The techniques are applicable to transferring relatively large files, for example in excess of 1 Gigabyte, and relatively smaller files in network environments that are relatively less reliable.