ACR

1. Attenuation-to-Crosstalk Ratio. Also known as headroom.The level of signal attenuation divided by the near-end crosstalk (NEXT), expressed in decibels (dB). If the level of crosstalk equals the level of the attenuated signal at any point in the cable, the signal is lost. See also attenuation, crosstalk, dB, NEXT, and signal. 2. Anonymous Call Rejection. See anonymous call rejection.

• North American Numbering Council (NANC)
• North American Numbering Plan (NANP)
• North American Time Division Multiple Access (NA-TDMA)
• NOS (Network Operating System)
• notation
• Not To Act Like It)
• Novel Services)
• NPAC (Number Portability Administration Center)
• NPA (Numbering Plan Administration)
• N-PCS (Narrowband Personal Communications Services)
• NREN (National Research and Education Network)
• nrt
• nrt-VBR (non real-time Variable Bit Rate)
• NRZ (Non-Return-to-Zero)
• NSF (National Science Foundation)
• NT1 (Network Termination 1)
• NT1 (Network Termination 1)
• NT2 (Network Termination 2)
• NT2 (Network Termination 2)
• NTACS (Narrowband Total Access Communications System)
• NTIA
• NT (Network Termination)
• NTSC (National Television Standards Committee)
• null
• null modem