Title: Generic Multi-Network Channel Simulator

Aliases: PHEME

Technical Challenge: The Generic Multi-Network Simulator program allows a personal computer to function as a multi-network communication channel simulator to predict how various communications equipments will perform over a variety of industry defined and user defined networks.

Description: This unique design allows the user to cascade up to four networks together in either real time or non-real time mode to predict the effects of multiple channels on the particular piece of equipment under test. The channel impairments of the cascaded networks are independent and cumulative, thus the simulator demonstrates the aggregate end-to-end channel effects that the data will likely encounter.

The simulator is run on a PC. By using a graphical user interface (GUI), the user selects the number, type, and order of the networks that he would like to see his communications signal sent through. Up to four networks can be cascaded to make up this simulated network. Each network type has predefined characteristics that the user can accept or customize by editing them via a GUI.

With this one program, one can simulate in real time at various data rates (300, 600, 1200, 2400, 4800, 9600, 19200 bps) the interconnection of various (wired/wireless, satellite, cellular) communications networks (PSTN, ISDN, ATM, TCP/IP, IS-95, IS-136, AMPS, GSM, Globalstar, Iridium, or a user defined network) and the overall effect of these networks on the communications system under test. Each network is defined to contain any or all of the following types of network errors: frame loss, frame error, extra frame, random errors, phase hit, or out of order frames.

The simulator inserts network impairments independently and cumulatively. The user can view the actual number of impairments inserted by each independent network and for the entire communications link. The user can also create, via a GUI, his own unique network with its own network impairment profile. The simulator can be run in real-time mode where the data is transmitted between the two test terminals through the simulator via two asynchronous serial ports on the PC. The simulator can also be run in non real-time mode where the data is read from an input file that is fed through the simulator and then stored into an output file.

    Demonstration Capability: The technology can be demonstrated on a Pentium computer running the Windows operating system with dual serial ports. A demonstration of the real-time mode would also require two additional computers, each having at least one serial port, and two null modem cables.

    Potential Commercial Application(s): Designers of communications protocols, security protocols, synchronization schemes, etc. could find this simulation tool very useful in determining how their various communications equipments will perform over a variety of industry defined and user defined networks before going to the great expense of actual field testing.

    (Updated) Patent Status: Issued: United States Patent Number 6,618,696

    Reference Number: 1119-1

    If you are interested in exploring this technology further, please call 443-445-7159 or express your interest in writing to the National Security Agency, Domestic Technology Transfer Program, 9800 Savage Road, Suite 6541, Fort George G. Meade, Maryland 20755-6541.