CPE mode is used at client side and CO mode is at central side. The CPE or CO mode can be adjusted by using a built-in DIP switch. For point-to-point connection, a CPE mode VC-234 and a CO mode VC-234 must be setup as one pair of converters to perform the connection.
The VC-234 also defines symmetric band plan for the transmission of upstream and downstream signals; the band plan performs higher transmission quality in short range for central side (CO) in symmetric mode. In all, when the VC-234 is in profile 17a operation mode, it provides long distance transmit with Ultra-high performance to the pervasive telephone line network, and when the VC-234 is in 30a operation mode, it gives short distance transmits with upstream and downstream transmission giving wire speed performance.