Errored second: Difference between revisions

Revision as of 08:11, 2 January 2011

Latest revision as of 16:24, 3 March 2025

(12 intermediate revisions by 7 users not shown)

Line 1:

{{Short description|Metric for digital communication link}}

In [[telecommunications]] and [[data communication]] systems, an '''errored second''' is an interval of a [[second]] during which any error whatsoever has occurred, regardless of whether that error was a single bit error, or a complete loss of communication for that entire second, is not important for the purpose of counting errored seconds.

In [[telecommunications]] and [[data communication]] systems, an '''errored second''' is an interval of a [[second]] during which any error whatsoever has occurred, regardless of whether that error was a single bit error, or a complete loss of communication for that entire second,. The type of error is not important for the purpose of counting errored seconds.

In communication systems with very low uncorrected [[bit error rate]]s, such as modern fiber optic systems, errored seconds are often a better measure of effective error rate than simple bit error rate. For many modern communication systems, even a single uncorrected bit error is enough to cause the loss of a [[data packet]] by causing its [[CRC]] to fail; whether that packet loss was caused by a single bit error or a burst of a hundred-bit-long [[error burst]] is irrelevant.

In communication systems with very low uncorrected [[bit error rate]]s, such as modern [[fiber-optic transmission system]]s, or systems with higher low-level error rates that are corrected using large amounts of [[forward error correction]], errored seconds are often a better measure of the effective user-visible error rate than the raw bit error rate.

More specialist and precise definitions of errored seconds exist in standards such as the [[T1]] and [[DS1]] transport systems.

In communication systems with very low uncorrected [[bit error rate]]s, such as modern fiber optic systems, errored seconds are often a better measure of effective error rate than simple bit error rate. For many modern packet-switched communication systems, even a single uncorrected bit error is enough to cause the loss of a [[data packet]] by causing its [[CRC check]] to fail; whether that packet loss was caused by a single bit error or a burst of a hundred-bit-long [[error burst]] is irrelevant.

== See also ==

* [[Degraded minute]]

* [[Severely errored second]]

For systems using large amounts of forward error correction, the reverse applies; a single low-level bit error will almost never occur, since any small errors will almost always be corrected, but any error sufficiently large to cause the forward error correction to fail will almost always result in a large burst error.

== External links ==

More specialist and precise definitions of errored seconds exist in standards such as the [[Digital Signal 1|T1]] and [[Digital Signal 1|DS1]] transport systems.

== References ==

* [http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00800f2fa1.shtml Cisco DS1, T1 and E1 Glossary]

Line 17 ⟶ 19:

[[Category:Data transmission]]

[[Category:Network performance]]

[[Category:Error measures]]

[[Category:Telecommunications]]