What Does Communication and Networking Riser Mean?
A Communications and Networking Riser (CNR) is a riser card developed by Intel for the advanced technology extended (ATX) family of motherboards. It is used for specialized networking, audio and telephony equipment. When introduced, CNR offered savings to motherboard manufacturers by removing analog I/O components from the motherboard.
While CNR slots were common on Pentium 4 motherboards, they have largely been phased out in favor of on-board or embedded components.
Techopedia Explains Communication and Networking Riser
The CNR specification is open to the industry. It was used to inexpensively integrate local area networks, modems and audio subsystems with personal computers. It supports broadband, multichannel audio, analog modem and Ethernet-based networking. CNR can also be expanded to meet the requirements of new technologies such as DSL. CNR is a scalable motherboard riser card and interface that supports audio, modem and network interfaces of core logic chipsets. CNR has the capability to minimize electrical noise interference by physically separating the noise-sensitive elements from the motherboard’s communication system.