This is part of the CCNA1 Introduction to Networks course. This page will be updated with texts in the future… for now, please refer to my lecture on my YouTube channel.

• Before any network communications can occur, a physical connection to a local network, either wired or wireless, must be established.
• The physical layer consists of electronic circuitry, media, and connectors developed by engineers.
• The physical layer standards address three functional areas: physical components, encoding, and signaling.
• Three types of copper cabling are: UTP, STP, and coaxial cable (coax).
• UTP cabling conforms to the standards established jointly by the TIA/EIA. The electrical characteristics of copper cabling are defined by the Institute of Electrical and Electronics Engineers (IEEE).
• The main cable types that are obtained by using specific wiring conventions are Ethernet Straight-through and Ethernet Crossover.
• Optical fiber cable transmits data over longer distances and at higher bandwidths than any other networking media.
• There are four types of fiber-optic connectors: ST, SC, LC, and duplex multimode LC.
• Fiber-optic patch cords include SC-SC multimode, LC-LC single-mode, ST-LC multimode, and SC-ST single-mode.
• Wireless media carry electromagnetic signals that represent the binary digits of data communications using radio or microwave frequencies. Wireless does have some limitations, including coverage area, interference, security, and the problems that occur with any shared medium.
• Wireless standards include the following: Wi-Fi (IEEE 802.11), Bluetooth (IEEE 802.15), WiMAX (IEEE 802.16), and Zigbee (IEEE 802.15.4).
• Wireless LAN (WLAN) requires a wireless AP and wireless NIC adapters.