Cyber Insurance & Security Glossary

XMPP which stands for Extensible Messaging and Presence Protocol, is a communications protocol for messaging systems. It is based on XML, storing and transmitting data in that format. It is used for sending and receiving instant messages, maintaining buddy lists, and broadcasting the status of one’s online presence. XMPP is an open protocol standard. Anyone can operate their own XMPP service, and use it to interact with any other XMPP service. The standard is maintained by XSF, the XMPP Standards Foundation.

XMT is also called Transmit. XMT is the method of sending data to an alternate computer or device.

XNS is short for Xerox Network Services, XNS is a proprietary network communications protocol developed by Xerox. XNS is no longer used and has been replaced by Transmission Control Protocol / Interface Program (TCP/IP).

Y2K is short for Year 2000 Bug or the millennium bug. Y2K is a warning first published by Bob Bemer in 1971 describing the issues of computers using a two-digit year date stamp.

A Ymodem is a file-transfer protocol developed by Chuck Forsburg, that is similar to the enhanced 1K version of Xmodem. Ymodem sends data in 1024-byte blocks, allows for multiple file transmissions at once, performs cyclical redundancy checks (CRC), and can reduce the transfer size to compensate for poor connections.

Yottabyte is abbreviated as YB. A yottabyte is equal to 1,208,925,819,614,629,174,706,176 (280) bits, or 1,000,000,000,000,000,000,000,000 (1024) bytes and is the largest recognized value used with storage.

A zero-day vulnerability is a flaw in the software, hardware or firmware that is unknown to the responsible parties for patching or fixing the flaw.

A zero-day (or zero-hour or day zero) attack is a computer threat that attempts to manipulate the computer application vulnerabilities that are undisclosed to the software developer. Zero-day exploits is the actual code that can use a security hole to carry out an attack. These exploits are used or shared by attackers before the software developer knows about the vulnerability.

A zombie is an infected computer that is remotely controlled by a hacker. It is part of a large group of compromised computers called a botnet.