K56flex

56k modems are voiceband modems capable of download speeds near 56 kbit/s (7 KByte/s) when connecting to a service that has ISDN or other digital connection to the phone network. The upload speed is usually limited to 33.6 kbit/s though the late arriving V92 standard increased this to 48 kbit/s. Due to the design of public telecomunications networks higher speed dialup modems are unlikely to ever appear. 56K modems can only work at 56K when there is only a single conversion between analog and digital in the path between the modem and the digital equipment at the provider. When this is not the case or when two 56k modems are used to communicate with each other they will generally fall back to 33.6 kbit/s V32bis.
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<protocol> A modem standard developed by Rockwell for 56 kbps communications. K56flex Became more popular than the rival X2 but will be superseded by the official V.90 standard.
[Already superseded?]
(1998-09-08)