Duplex Half Duplex and Simplex NIC Settings include the direction in which

Duplex half duplex and simplex nic settings include

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Duplex, Half Duplex and Simplex NIC Settings include the direction in which signals travel over the media and the number of signals that can traverse the media at any given time These two are combined to create different methods of communication Full-duplex- Also called duplex Signals travel in both directions over a medium simultaneously Half-Duplex Signals may travel in both directions but only in one direction at a time Simplex Signals may travel in only one direction and is sometimes called one-way or unidirectional, communication Multiplexing: A form of transmission that allows multiple signals to travel simultaneously over one medium Subchannels: Logical multiple smaller channels
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Multiplexer (Mux): combines many channel signals, required at the transmitting end of the channel Demultiplexer (Demux): Separates the combined signalsThree types of Multiplexing are used on copper lines: 1. TDM (time division multiplexing): divides channel into multiple time intervals 2. STDM (statistical time division multiplexing): - Transmitter assigns slots to nodes (according to priority and need) - Maximizes available bandwidth on a network 3. FDM (Frequency division multiplexing): Assigns different frequency band for each communications subchannel Three types of Multiplexing are used on fibre-optic cable: 1. WDM (wavelength division multiplexing): carries multiple light signals simultaneously by dividing a light beam into different wavelengths or colours. 2. DWDM (Dense wavelength division multiplexing): extraordinary capacity, typically used on high-bandwidth or long-distance WAN links 3. CWDM (Coarse wavelength division multiplexing): channels are spaced out more widely apart across entire frequency band, effective distance is more limited because the signal is not amplified. Copper Cable: Coaxial cable is considered a “legacy” cable. Twisted-Pair Cable: colour-coded insulated copper wire pairs: - 0.4-0.8mm diameter - Encased in a plastic sheath - Every two wires are twisted together Twisted-pair cabling in Ethernet networks contains four wire pairs: Fast Ethernet uses one pair to send data and one pair to receive data Networks using Gigabit Ethernet use all four pairs for both sending and receiving Wiring standard specification TIA/EIA 568
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Most common twisted pair types: Category (cat) 3,5,5e,6,6a and 7 CAT 5e or higher used in modern LANs Two categories: Shielded twisted pair (STP) o Individually insulated o Surrounded by metallic substance shielding (foil) Barrier to external electromagnetic forces Contains electrical energy of signals inside Must be grounded Unshielded twisted “ (UTP): One or more insulates wire pairs encased in plastic sheath: No additional shielding Less expensive, less noise resistance Comparing STP and UTP Throughput- STP and UTP can transmit the same rates Cost- STP and UTP vary in cost, STP is more expensive than UTP Connector- STP and UTP use registered Jack 45 Noise Immunity- STP is more noise resistant Size and Scalability- Maximum segment length for both: 100 meters on Ethernet netwoorks that support data rates from 1 Mbps and 10 Gbps Cable Pinouts Proper cable termination is a requirement for two nodes on a network to communicate
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