This layer usually incorporates Layer 2 switches and access points that provide connectivity between workstations and servers. You can manage access control and policy, create separate collision domains, and implement port security at this layer. For example, a switch that provides access-layer functionality is called an access switch, a switch that operates in the distribution layer is known as a distribution switch, and a switch that operates in the core layer is called a core switch. This layer serves as the network's outermost boundary and the gateway through which all data must pass. Selecting the right switch type has a direct impact on network scalability, performance, and management efficiency.
[pdf] A practical, engineering-focused guide to planning and installing underground fiber optic cables with the right cable structure, trench design and protection level for long-life, low-risk networks. Match trench method with the correct underground fiber structure (GYTS, GYTA53, GYTY53, micro-duct). Underground cables are pulled in conduit that is buried underground, usually 1-1. 2 meters (3-4 feet) deep to reduce the likelihood of accidentally being dug up.
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