Search results
Results from the WOW.Com Content Network
The Ethernet physical layer has evolved over its existence starting in 1980 and encompasses multiple physical media interfaces and several orders of magnitude of speed from 1 Mbit/s to 800 Gbit/s. The physical medium ranges from bulky coaxial cable to twisted pair and optical fiber with a standardized reach of
Where channels use line codes (such as Ethernet, Serial ATA, and PCI Express), quoted rates are for the decoded signal. The figures below are simplex data rates, which may conflict with the duplex rates vendors sometimes use in promotional materials.
Ethernet packet. The SFD (start frame delimiter) marks the end of the packet preamble. It is immediately followed by the Ethernet frame, which starts with the destination MAC address. [1] In computer networking, an Ethernet frame is a data link layer protocol data unit and uses the underlying Ethernet physical layer transport
Example 5: The downlink of a V.92 modem uses a pulse-amplitude modulation with 128 signal levels, resulting in N = 7 bit/symbol. Since the transmitted signal before passband filtering can be considered as baseband transmission, the spectral efficiency cannot exceed 2N = 14 (bit/s)/Hz over the full baseband channel (0 to 4 kHz). As seen above, a ...
Most Ethernet cables are wired straight-through (pin 1 to pin 1, pin 2 to pin 2, and so on). In some instances, the crossover form (receive to transmit and transmit to receive) may still be required. A cable for Ethernet may be wired to either the T568A or T568B termination standard at both ends of the cable. Since these standards differ only ...
According to the original Ethernet protocol, a signal sent out over the collision domain must reach every part of the network within a specified length of time. The 5-4-3 rule ensures this. Each segment and repeater that a signal goes through adds a small amount of time to the process, so the rule is designed to minimize transmission times of ...
The letter following the dash (T or F) refers to the physical medium that carries the signal (twisted pair or fiber, respectively), while the last character (X, 4, etc.) refers to the line code method used. Fast Ethernet is sometimes referred to as 100BASE-X, where X is a placeholder for the FX and TX variants. [4]
In computer networking, Gigabit Ethernet (GbE or 1 GigE) is the term applied to transmitting Ethernet frames at a rate of a gigabit per second. The most popular variant, 1000BASE-T , is defined by the IEEE 802.3ab standard.