In the late 1990s, ModSAF was taken over by the army wargaming operation (STRICOM, now PEO-Stri), with the intention of developing a tactical wargame that used all the good stuff that the commercial developers were turning out, and put it in a package that suited military needs. That was a long list of needs. The new game, OneSAF, had to be useful to the troops, as well as researchers (developers of new tactics, equipment and weapons). That meant a software package that was easy to modify and easy to use. By 2001, OneSAF had replaced ModSAF. The users were happy, and the developers used that good will to get more money, and freedom, to keep OneSAF up to date, and responsive to users.
To do all this, OneSAF had to, of necessity, become a revolutionary product. Consider its characteristics. OneSAF is free (to government and military developers) and is open source. That means it runs on a large number of systems (Windows, Linux, PDAs, supercomputers, Etc.). Its well documented and SME compliant. Also important is that the basic OneSAF package is a tool kit, which enables users to quickly adapt it to new uses. The core code was written by competent programmers, and the project is managed so that the code stays clean and easy to read. OneSAF also uses managed code, like JAVA, to make it accessible and easier to use and modify. The army really got behind the project, assigning its best people to supervise it. Several senior people on the project are former infantry officers, and have PhDs in computer science. The army has been sending infantry officers to graduate school, to study computer science, for several decades, and OneSAF was an example of how that policy paid off.
OneSAF can handle combat from the level of individual troops, up to brigade. In other words, its a tactical combat simulation. It can be plugged into higher level wargames (like WARSIM), so that a theater commander can drill down to see how street fighting in Fallujah is going, to draw back to see how forces are deployed, and operating, for everything from the Middle East to Afghanistan. This was done by building both systems so they could read the same data, and basically talk to each other. To further enhance this integration, many WARSIM developers have moved over (since WARSIM was put into service this year) to work on One SAF.
To do all this, OneSAF uses digitalized military maps and much of the electronic data already available from actual units. The software deals with huge range of military factors, far more than your typical commercial wargame. For example, it can handle casualty care (who got hurt, to what extent and what can be done to help them), accuracy and effectiveness of weapons from hand grenades up to long range army missiles (and missiles of all sorts). The game can accurately represent helicopters (transport and attack) and ground vehicles from trucks to tanks. It deals with anti-aircraft systems, from ground fire (firing an assault rifle at something up there) to Patriot missiles. This includes modeling radar systems. It deals with mines, NBC (chemical, biological and nuclear), electronic warfare (and all sorts of communications), laser designators, and all sorts of damage to weapons, equipment and troops. It also handles logistics and a most of the reporting units usually do to each other. In short, its a pretty comprehensive wargame. Because its easy to modify, new types of weapons (like roadside bombs) can be modeled. When it was seen how effective current tactics were in keeping casualties down in Iraq and Afghanistan, it was easy to modify the casualty routines to reflect this new reality.
OneSAF is in the process of replacing a number of older wargames (JANUS, JCATS, and so on). That will start happening next year. With OneSAF, its now practical for unit commanders to use a wargame to plan and practice field exercises (over maps of the actual terrain they will be using). This makes those exercises a lot cheaper, and safer for the troops. Using OneSAF this way enables commanders to use the game for planning actual operations, again saving the lives of troops who, in the past ran into something unexpected (to conventional planning methods.)
OneSAF has been something of a stealth project. A lot of people in the military, and a few outside, have heard of it. But few knew what it all really meant. Now you do.
In the early 1990s, the U.S. Army began developing a software system that could model (wargame) friendly or enemy forces at the tactical (battalion and lower) `level, and be used in larger wargames as well, when more detail had to be shown. The result of this effort was ModSAF (Modular Semi-Automated Forces). The army had previously been working on the AI (artificial intelligence) problem, which led to the ongoing semi-automated forces project. It had been noted that the AI in commercial games was getting much better, but that was because there were two schools of thought on AI. The academic side, which the military depended on, expected perfection. That is hard to achieve, and expensive as well. Tactical level wargames require a lot of AI to function at all, The commercial developers just wanted something that worked, and, increasingly, they were getting impressive results. While ModSAF was a good effort at applying effective AI (that was acceptable to the powers-that-be in the army scientific community), many army developers and scientists realized that more could be done.