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3. Basic Concept and
Management
This chapter will tell you the basic concept of features to manage this switch
and how they work.
3-1. What’s the 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 operated at
100Mbps, called Fast Ethernet now. This means Fast Ethernet inherits the same
frame format, CSMA/CD, software interface. In 1998, Gigabit Ethernet was rolled
out and provided 1000Mbps. Now 10G/s Ethernet is under approving. Although
these Ethernet have different speed, they still use the same basic functions. So they
are compatible in software and can connect each other almost without limitation.
The transmission media may be the only problem.
Fig. 3-1 IEEE 802.3 reference model vs. OSI reference mode
In Fig. 3-1, we can see that Ethernet locates at the Data Link layer and
Physical layer and comprises three portions, including logical link control (LLC),
media access control (MAC), and physical layer. The first two comprises Data link
layer, which performs splitting data into frame for transmitting, receiving
acknowledge frame, error checking and re-transmitting when not received correctly
as well as provides an error-free channel upward to network layer.