In this layer, the layer 2 switches are installed to distribute the data packets to the addressed group of access devices. When planning an enterprise access network, one of the most common dilemmas is whether to deploy Layer 2 (L2) or Layer 3 (L3) switches. The access layer plays a critical role in connecting end devices—such as computers, printers, IP phones, and wireless access points—to the rest of the enterprise. A Layer-2 switch works at the Data Link layer or Layer 2 of the OSI reference model.
[pdf] Optical devices are optoelectronic components used in optical communication that perform various functions based on the photoelectric conversion effect. Depending on whether photoelectric conversion occurs during operation, optical devices can be divided into active devices and passive. Optoelectronics (or optronics) is the study and application of electronic devices and systems that find, detect and control light, usually considered a sub-field of photonics.
[pdf] It is always advisable to plot the curves of relays and other protection devices, such as fuses, that are to operate in series, on a common scale. An Overcurrent Relay Setting Calculator helps engineers, electricians, and technicians determine the correct pickup current, time multiplier. This handbook covers the code of practice in protection circuitry including standard lead and device numbers, mode of connections at terminal strips, colour codes in multicore cables, dos and donts in execution. Many important issues, such as coordination of settings, operating times, characteristics of.
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