The CSD 4100 has all the telephone options wanted by busy executives. The distinctive advantage of the STU-III Secure Voice Device, Model 2600/3600, is that the users can "go secure" without losing the features and functionality of their present phone system. While most individual conversations are unclassified in themselves, sensitive data will be gathered by way of evaluation of daily routine voice communications. A brand new key is negotiated at each communications session utilizing public key encryption, whereas personal key system provides message authentication and certification. When keyed, it carries the classification stage of the visitors key loaded into the host gear. This information consists of the level of security authorized for that terminal. The CSD 4100 has a wide range of security layers for optimum communications safety. The SDD offers protection for facsimiles, e-mail, and laptop communications. Protects phone calls, facsimiles, digital mail and laptop communications. It was decided to equip Pearl Harbor and Cavite with 350-kw. arc transmitters capable of direct communications with one another, thereby eliminating the requirement of relaying via Samoa and Guam.

Granite Island Group provides a full line of communications and technical security merchandise ranging from inexpensive physique worn bug detectors and encryption tools, to full TSCM deployment kits suitable for prime threat company and diplomatic TSCM inspections. The CTAC Ciphertac safety module is certified for all ranges of categorized discussions as much as and including SECRET in an satisfactory operating/safety surroundings. CTAC without an inserted CipherTAC 2000 security module is unclassified and features as a non-secure business off the shelf (COTS) phone product. The Motorola CipherTAC 2000 (CTAC) STU-III family suitable safe voice communications through cellular telephone. While the quality will be improved by using a purely digital STE, the communications infrastructure is rarely in a position to assist their widespread utilization. Note the cautions regarding cellular or radio utilization and crypto given further down on this web page. Only customers with a crypto ignition key matching the serial number programmed into the CSD 4100 can function the secure unit.

The CSD 3600 generates and distributes keys utilizing negotiated public key encryption. Even essentially the most refined cryptographic algorithm may be easily expressed within the form of a simple equation in boolean algebra, with the "initialization keys" being used to outline the initial key generator settings, and to supply morphing again to the equation. The "keying stream" is created by the "Key Generator" and is the actual coronary heart of the STU. This transmitter was replaced shortly thereafter by a 60-kw. arc, powered by a General Electric Co. 500-volt, direct-present, railroad-sort generator. Now if this wasn't confusing sufficient; portable Inmarsat stations also present the same drawback, however only if the STU is positioned in front of the transmitter antenna or within the side lobes of the signal (about 45 degrees off the middle axis of the antenna). This six to ten wavelengths is referred to because the "close to discipline" or the wave front where the magnetic subject of the signal is stronger then the electrical discipline.

Once the eavesdropper has the important thing, then the communication itself could be focused and exploited. A portion of the "keying stream" are then mixed again into to the unique key, and course of repeated. The solution was to deliver a sign into the room from exterior, a venture that might involve a obtain antenna placed in a location that did have a great signal - such as the roof of the building - and then convey it to the conference room and by some means couple it to the clocks in query. The STU should at all times be positioned in an area known as an exclusion zone, and cellular phones, pagers, beepers, and different RF devices ought to be kept outside of a stand-off zone of not less than 15-20 toes (30 foot is nice practice). This is named the "saturation effect", and if it isn't correctly addressed can end result within the cryptographic equipment put vulnerable to disclosing secrets. James M. Atkinson, 1982 Equipment Pedigree On a remaining observe; customers of cryptographic gear should be very cautious and involved the place the encryption gear is coming from, who makes it, and who handles it whereas in transit from the manufacturing facility. AT&T STU-III Secure Data Device, Model 2900 The STU-III telephone was developed to protect sensitive and labeled info by the use of a secure means simply accessible to a large number of customers.