text: by national technical means, that is primarily photo-reconnaissance satellites. It permits laboratory research for space-based BMD systems. It prohibits field testing of prototypes of such systems or components. The Treaty does not prohibit development and testing of fixed, ground-based BMD laser systems and their components. It also permits the development and testing and deployment of space-based laser devices, such as pointing and tracking devices as long as the devices are not capable of countering strategic ballistic missiles or their elements in flight trajectory and as long as they are not tested in ABM mode. The Treaty thus permits testing of sub-components for space-based BMD lasers while prohibiting component or full systems testing, and, more importantly, deployment of such systems. The Treaty also permits research into all types of BMD systems . 13« The Treaty does not define what "space based" actually constitutes because of international difference of opinion as to where the boundaries between national air space and outer space lie. This topic has been under discussion in UNCOPUOS. The ABM Treaty does not restrict development, testing and deployment of space-based ASATs, however armed. In common with other States Parties, however, both the United States and the Soviet Union may not deploy nuclear armed space-based ASATs as they are both parties to the Outer Space Treaty. In addition to this, as part of the provisions of the ABM Treaty, an ASAT system may not be given capabilities to counter strategic ballistic missiles or their elements in flight trajectory and may not be tested in an ABM mode. 14. Although SALT II Treaty (signed at Vienna in June 1979) remains unratified, both the United States and the Soviet Union have stated that they will abide by its provisions as long as its provisions are respected by the other Party. In 
analysis: The text appears to be discussing international agreements and treaties related to the development and deployment of space-based ballistic missile defense (BMD) systems, anti-ballistic missiles (ABM), and anti-satellite weapons (ASAT). The language used is technical and focused on the capabilities and limitations of these systems, suggesting that the text is primarily concerned with scientific and technological issues.