Rollover cable (also known as a Yost cable, Cisco cable, or a Console cable) is a type of
null-modem
Null modem is a communication method to directly connect two DTEs ( computer, terminal, printer, etc.) using an RS-232 serial cable. The name stems from the historical use of RS-232 cables to connect two teleprinter devices or two modems in ord ...
cable that is used to connect a
computer terminal
A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. The teletype was an example of an early-day hard-copy terminal and ...
to a router's
console
Console may refer to:
Computing and video games
* System console, a physical device to operate a computer
** Virtual console, a user interface for multiple computer consoles on one device
** Command-line interface, a method of interacting with ...
port. This cable is typically flat (and has a light blue color) to help distinguish it from other types of network cabling. It gets the name rollover because the
pinouts
In electronics, a pinout (sometimes written "pin-out") is a cross-reference between the contacts, or ''pins'', of an electrical connector or electronic component, and their functions. "Pinout" now supersedes the term "basing diagram" that was the s ...
on one end are reversed from the other, as if the wire had been rolled over and you were viewing it from the other side.
This cabling system was invented to eliminate the differences in
RS-232 wiring systems. Any two RS-232 systems can be directly connected by a standard rollover cable and a standard connector. For
legacy equipment, an adapter is permanently attached to the
legacy port
In computing, a legacy port is a computer port or connector that is considered by some to be fully or partially superseded. The replacement ports usually provide most of the functionality of the legacy ports with higher speeds, more compact desi ...
.
See also
*
8P8C
A modular connector is a type of electrical connector for cords and cables of electronic devices and appliances, such as in computer networking, telecommunication equipment, and audio headsets.
Modular connectors were originally developed for ...
*
Serial cable
A serial cable is a cable used to transfer information between two devices using a serial communication protocol. The form of connectors depends on the particular serial port used. A cable wired for connecting two DTEs directly is known as a null ...
*
RS-232
In telecommunications, RS-232 or Recommended Standard 232 is a standard originally introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' (''data terminal equipment'') such a ...
References
*
Cisco
Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational digital communications technology conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, ...
Cabling Guide for Console and AUX PortsDocument ID: 12223
Dave Yost Serial Device Wiring Standard
External links
*{{Commonscatinline
Out-of-band management
Signal cables