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Fiber Optics Illustrated Dictionary - Part 21

The Fiber Optics Illustrated Dictionary - Part 21 fills a gap in the literature by providing instructors, hobbyists, and top-level engineers with an accessible, current reference. From the author of the best-selling Telecommunications Illustrated Dictionary, this comprehensive reference includes fundamental physics, basic technical information for fiber splicing, installation, maintenance, and repair, and follow-up information for communications and other professionals using fiber optic components. Well-balanced, well-researched, and extensively cross-referenced, it also includes hundreds of photographs, charts, and diagrams that clarify the more complex ideas and put simpler ideas into their applications context | Fiber Optics Illustrated Dictionary code rejects In packet networking codes that are not used or not recognized are processed as code rejects codec encode decode coder decoder. A system to convert analog signals such as video and voice to digital signals for transmission then back to analog at the destination. Codec mechanisms were originally installed on trunk lines but as the cost of electronics dropped they moved closer and closer to the home and office until now with systems such as DSL the codec is installed and performed right on the premises. Contrast with modem. coded mark inversion CMI. In SONET and SDH networks a two-level non-retum-to-zero coding scheme. Binary values are coded in relation to a binary unit time interval T . A one 1 is coded for a full time interval at one of two amplitude levels low and high such that the level alternates for successive ones. A zero 0 is coded by a positive transition from one to the other consecutive amplitude level at the midpoint of the time interval for half a binary unit time interval T 2 . Code Red An intrusive program called a worm that used a unicode encoding technique to infect systems. A buffer overflow vulnerability in the indexing server was exploited to insert the worm onto a new system. Once a system had been infected the worm used it to perform denial of service attacks on www.whitehouse.gov and in some cases defaced the server s home page. It spread by randomly generating IP addresses for new systems to infect. Windows NT and Windows 2000 systems using the Microsoft Internet Information Server IIS were vulnerable. In response vendors such as Cisco Systems took steps to update systems to prevent this type of security breach and Microsoft issued a Security Bulletin MSO1-033 with information on patches. coding violation CV. In ATM networking a coding violation results when bit interleaved parity errors are detected on an incoming signal. Each BIP error typically up to 8 16 or 24 increments a CV counter. In .