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] Kevlar® is the registered trademark for the strong synthetic material or yellow 'hair' used as a protective outer sheath for the glass fiber core it protects. Its high tensile strength protects the cable from damage when being pulled. Structurally, a fiber cable comprises the core, cladding, coating, strength member, and outer jacket. The fiber jacket protects against moisture, UV exposure, chemicals, and mechanical abrasion. Larger core sizes allow a larger amount of light, or a larger beam diameter, to enter the fiber. The numerical aperture. A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry light. Many factors influence the design of fiber-optic cables.
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