TTL


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TTL

TTL

(1)

TTL

(2)

TTL

(1) (Time To Live) A counter in a network packet that sets a limit to its validity. In order to prevent an IP packet from propagating endlessly through the network, the value in the TTL field is reduced by each router. When TTL reaches 0, the packet is discarded.

(2) (Time To Live) A timestamp in the DNS system, which converts hostnames to IP addresses. Responses use a TTL field to keep the IP address in the user's cache for a limited amount of time. After the time is up, the next request for that IP address must go back to the DNS system. See DNS and DNS rebinding.

(3) (Transistor-Transistor Logic) A digital circuit composed of bipolar junction transistors (BJTs). Widely used in all variety of electronic applications, especially prior to CMOS circuits becoming popular, TTL superseded the earlier RTL (resistor-transistor) and DTL (diode-transistor) logic designs, which used more power. In TTL, transistors are used to both isolate inputs and perform the logic switching. A "TTL" designation on a circuit input or output indicates a digital circuit rather than analog. See 7400 series, ECL, I2L and bipolar transistor.

(4) (Through The Lens) Refers to a single-lens reflex camera that lets the photographer view the scene through the same lens that captures the image. "TTL metering" means that the light is measured from behind the lens to determine the correct shutter and flash settings.
References in periodicals archive ?
Just as important as the content of a document such as TTL is the discussion it creates among the churches and the churches' feedback to the Commission on World Mission and Evangelism (CWME).
Rob Pope, managing director of TTL said: "We have been at the forefront of CNC machining technology for many years and are proud and delighted to be part of the Manufacturing Technology Centre community."
TTL reports that its revenue in 2012 had reached NT$60.968 billion (US$2.032 billion) by the end of September, amounting to 78% of its annual revenue target of NT$79.147 billion (US$2.638 billion).
For FY10, TTL has net sales of Rs.342.93 crore with a PAT of Rs.76 crore.
We also rank the sensitivity value by scaling it with the one with the largest magnitude in the column, to provide a ranked estimate of its relative importance on TTL. Sensitivity analysis also serves as an additional tool to check whether the model has generalized adequately since it can be checked against known trends reported in the literature.
In psychoanalytic readings of TTL, notions of subjectivity constituted in loss or defeat posit the final moments of TTL as the resolution of Lily Briscoe's oedipal dilemma.
TTL's 40-strong team of academics, scientists and managers will now play a key part in ambitious plans to establish a global network of telescopes.
The Teacher Technology Leaders (TTL) Project is well into the third year of its activities.
It connects to a host terminal or computer via flex cable, and its TTL output can be configured to be compatible with any other reader.
Frequency setting is a TTL 16 bit parallel data word on J2.
Illumination includes the patented LED SmartRing light, coaxial (TTL) surface illuminator, fiber optic ring light, and LED back light.