Glossary
Technology evolves at a rapid-fire pace. That’s why we’ve built an easy-to-use glossary to help you better understand the terms, technologies and trends that impact your business.Channel Service Unit (CSU)
A network device that receives and transmits signals to and from the wide-area-network (WAN) line. The CSU performs loopback testing of signals from the phone company and provides a barrier for electrical interference from either side of the unit (customer premises or phone company).