Definity TN464HP Circuit Cards
The TN464HP DS1 interface is intended for customers who are likely to encounter echo. This echo can be over circuits that are connected to the public network. The occurrence of echo is higher if the switch is configured for ATM, IP, or other complex services and interfaces to certain local service providers. These local service providers do not routinely install echo cancellation equipment in all their circuits. A common source of echo is "hybrid" circuits, where conversions between 2-wire analog circuits and 4-wire digital circuits take place. The TN464HP DS1 interface cancels echo with delays of up to 96 milliseconds.