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Chapter 4: Basic Concepts and Management
4. Basic Concepts and Management
This chapter describes the features used to manage this switch and how they work.
4.1 Ethernet
Ethernet originated and was implemented at Xerox® in Palo Alto, CA in 1973 and was successfully commercialized by Digital
Equipment Corporation (DEC), Intel® and Xerox (DIX) in 1980. In 1992, Grand Junction Networks unveiled a new high-speed
Ethernet with the same characteristic of the original Ethernet but operating at 100 Mbps, now called Fast Ethernet. This means
Fast Ethernet inherits the same frame format, CSMA/CD, software interface. In 1998, Gigabit Ethernet was rolled out and
provided 1000 Mbps. The 10 Gbps Ethernet standard was released in 2002. Although these types of Ethernet have different
speeds, they still use the same basic functions. They are software compatible and can connect to each other almost without
limitation, based on the transmission media used.
Figure 4-1. IEEE 802.3 reference model vs. OSI reference mode.
In Figure 4-1, Ethernet uses the Data Link layer and Physical layer and consists of three portions, including logical link control (LLC),
media access control (MAC), and physical layer. The first two portions work at the Data link layer, which splits data into frames for
transmitting, receiving acknowledge frames, error checking, and re-transmitting when not received correctly, and also provides an
error-free channel upward to the network layer.