Advanced Warfare Environment serial-to-socket conversion program helps soldiers 'get the picture'

Army Communicator, Spring, 2003 by Tim Sellers, Marc Neely

Communicators in every position around the world are concerned with moving information. Whether it's voice, video or data, the communicator's job is to ensure the message reaches its intended recipient. "Getting the message through" is a touchstone for communicators everywhere.

Meeting this mission, however, is easier said than done. Creativity and innovation mark the efforts of Signal officers everywhere in looking for new ways to transmit and receive information. Sometimes innovation means developing new technology, but more often, it means making minor improvements to existing technology. These minor improvements have the potential to yield significant results.

The Advanced Warfare Environment serial-to-socket conversion program is one such minor improvement for serial-data transmission. Overcoming many shortcomings of traditional serial-data links, it augments a proven transmission method and significantly enhances the ability to share information, such as a common operational picture, in real-time.

The Army's air-defense community relies heavily on serial communications to receive and display tactical-air picture data. Although tactical data links use a variety of transmission means and protocols, the final link with the intended processor is almost always a serial connection. These connections are made with RS-232 cables over very short distances (less than 25 feet). Data rates vary but are normally no more than 19,200 bits per second. Serial communications are perfectly suited for these types of links, as they offer a simple, fast and reliable way of transmitting data at low speed.

There are, however, limitations to serial transmission. First, cable lengths are very short, forcing co-location of the processor with the data source. This means that antennas with line-of-sight and radio-frequency propagation requirements will sometimes conflict with the processor's required location. Although secure telephones can overcome this limitation (greatly increasing the distance between receiver and processor), the connection becomes more complicated, requiring the dedication of precious secure telephony assets, and remains point-to-point in nature.

This type of one-to-one communication is a second limitation of serial communications. As seen in (Figure 1), the traditional serial link, even over secure telephone, still represents one serial source communicating with only one processor. A means for distributing one feed or stream of serial data to multiple processors over distances greater than 25 feet is needed.

[FIGURE 1 OMITTED]

The third, and perhaps most significant, limitation of serial communications to the air defender is the difficulty in obtaining a single integrated air picture. The SIAP is critical to a properly executed air-defense plan. Decision-makers at command-and-control elements must possess the same air picture as the shooter to correctly process information and control engagements. (Note: The corollary isn't true; the shooter doesn't require all the decision-maker's information.) Often, because of distance or availability, shooters may obtain air-picture data from one source, while decision-makers receive it from another. Either picture may be more or less accurate, causing a difference in perception of the battlespace and leading to difficulties in all aspects of executing the ADP.

The AWARE serial-to-socket conversion program mitigates all these limitations, significantly improving the ability to obtain and maintain the SLAP. Developed by Marc Neely of the Space and Missile-Defense Battle Lab in Huntsville, Ala., and validated in multiple joint and combined exercises, this tiny program (it fits on one 3 1/2-inch floppy disk) encapsulates serial data (frames) into Internet-protocol data (packets) for transport. The distant end receives the IP packets, strips the packet header and provides the serial data for the intended processor (Figure 2).

[FIGURE 2 OMITTED]

The program works exclusively at the network layer by encapsulating serial frames into IP packets. Format-independent, it allows any serial-data link to travel over any data-link layer protocol (for example, frame relay, asynchronous-transfer mode, ethernet) without changing the message format or the intended processor's configuration. The program installs on any Microsoft workstation or laptop. Data may be received and transmitted via serial, up/down protocol or transmission-control protocol, giving the program any-to-any protocol flexibility. Also, a single workstation can run multiple instances of the program--all with different receive and transmit protocols. Finally, the program can be configured as a TCP server, enabling multiple users to receive the same data simultaneously (Figure 3).

[FIGURE 3 OMITTED]

Future add-ons to the program include a serial-port checker as well as a virtual serial-breakout box that will enable the user to change serial pin-outs through software. Anyone who has ever tried to build a specially pinned-out serial cable from scratch will certainly appreciate this function.