| ==Phrack Inc.== | |
| Volume One, Issue Three, Phile 4 of 10 | |
| Signalling Systems Around the World | |
| For those of you who have the desire to make international calls, this info may | |
| be of interest. Thanks to TAP and Nick Haflinger. | |
| CCITT 1. An old international system, now deceased. Used a 500 Hz tone | |
| interrupted at 20 Hz (Ring) for 1-way line signals. | |
| CCITT 2. Proposed "International Standard" that never caught on much. | |
| Used 600 Hz interrupted by 750 Hz. Still used in Australia, | |
| New Zealand and South Africa. | |
| CCITT 3. An early in-band system that uses 2280 for both line and | |
| register (!!). Used in France, Austria, Poland and Hungary. | |
| CCITT 4 A variation of 3, but uses 2040 and 2400 for end to end Tx of | |
| line and register. Used for international Traffic in Europe, | |
| but cannot be used with TASI (AKA Multiplex or "that dammed | |
| clipping"). | |
| CCITT 5 This is the most popular, and the one used in the US. 2400 and | |
| the infamous 2600 are used for link to link (not merely end to | |
| end line signals. Registers are handled via DTMF (Touchtones). | |
| Anyone know what 2400 does?? | |
| CCITT 5 bis. Just like above, but a 1850 Hz tone is used for TASI locking | |
| and transmission of line signals. | |
| CCITT 6 The newest and worst for phreaks. It uses digital data sent | |
| out-of-band to control the connection. In other words, the | |
| connection is made and billing started BEFORE you can get | |
| control. | |
| CCITT 5R1 A regional system like 5, but doesn't use the mysterious 2400 | |
| and can't use the multiplexer. | |
| CCITT 5R2 Probably the interface to AUTOVON, as it uses 120 Hz spaced | |
| tones for DTMF instead of 200. Also 3825 Hz is the blow-off | |
| tone instead of 2600. | |
| The "Extra" tones | |
| 1700 + 700 = Inward Operator | |
| 1700 + 900 = Delay operator, also, in TSPS,STP (a "Zero Plus" call from a coin | |
| phone) | |
| 1700 + 1100= KP1 (Start recognition of special tones) | |
| 1300 + 1700= KP2 (End recognition of special tones) | |
| 12-85 Data Line. CIS 72767,3207: TWX 650-240-6356 | |