A Digital Signal 3 (DS3) is a digital signal level 3 T-carrier. It may also be referred to as a T3 line.
- The data rate for this type of signal is 44.736 Mbit/s.
- This level of carrier can transport 28 DS1 level signals within its payload.
- This level of carrier can transport 672 DS0 level channels within its payload.
Cabling
DS3 interconnect cables must be made with true 75 ohm cable and connectors. Cables or connectors which are 50 ohm or which significantly deviate from 75 ohms will result in reflections which will lower the performance of the connection, possibly to the point of it not working. Bellcore standard GR-139-CORE defines type 734 and 735 cables for this application. Due to losses, there are differing distance limitations for each type of cable. 734 has a larger center conductor and insulator for lower losses for a given distance. The BNC connectors are also very important as are the crimping and cable stripping tools used to install them. Trompeter, Cannon, Amphenol, Kings, and Canare are some of the true 7.5 x 10 ohm connectors known to work. RG-6 or even inexpensive RG-59 cable will work in a pinch when properly connectorized, though it does not meet telephony technical standards.
Usage
The level of transport or circuit is mostly used between telephony carriers, both wired and wireless.
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