Of the 3270 family, the 3278 and 3279 color displays are the most widely emulated. The 3178 and 3278 monochrome displays are also popular. If you need to display the full screen formats of the larger displays, each PC may need to be equipped with a VGA or better graphics adapter. In addition to terminal emulation, a gateway may also need to provide printer emulation. This will permit PC users to print mainframe data to their local and LAN printers.
File transfer is as essential as terminal emulation.
Most have a proprietary file transfer that is generally a great deal speedier than IBM's. On the other hand, that requires more memory on the PC side. The gateway should also allow users to transfer files in background mode. With background file transfer, a user can set up a file transfer and switch to an interactive terminal session while the transfer takes place. Most gateways allow users to have multiple, simultaneous sessions on the mainframe.