Networking and Infrastructure: Key Notes Network Infrastructure Components Network infrastructure forms the backbone of modern digital communication, comprising both physical and logical elements. Physical components include routers, switches, firewalls, servers, and cabling (fiber optic, copper, wireless). Logical components encompass IP addressing, subnets, VLANs, routing protocols (OSPF, BGP), and security policies. These elements work together to enable data transmission across local and wide area networks. Network Topologies and Architectures Common network topologies include star, mesh, and ring configurations, each with distinct advantages in redundancy and scalability. Modern enterprise networks often adopt hierarchical designs (core, distribution, access layers) to improve manageability and performance. Software-Defined Networking (SDN) decouples the control plane from the data plane, enabling centralized management and dynamic resource allocation. ...