Chapter 8: Ethernet, Ethernet, and More Ethernet 313
mine trafﬁc loads and patterns, user applications, location of users and servers, and type of
data transmissions. In some cases, giving attention to speciﬁc network administration
tasks might prove sufﬁcient. For example, Ethernet/802.3 performance and efﬁciency can
be improved through collision management, standards adherence, proper system conﬁgu-
rations, software upgrades, and segmentation using bridges. Nevertheless, there are certain
situations that lend themselves to switching. These include dynamic workgroup settings,
frequent data transmissions involving large data ﬁles such as graphical images, distributed
network environments that employ several servers, and LANs that must support video or
multimedia applications. If a decision to “switch” is made, remember that all switches are
not alike. Switches have different architectures, are designed for different types of applica-
tions, and some switches also have routing capabilities (called layer-3 switches). Once
again it is important to understand how a network is being used before modifying it.
41. What’s next?
100-Mbps Ethernet, 1000-Mbps Ethernet, and 10,000-Mbps Ethernet.
42. Why are these needed when switched and full-duplex Ethernet are available?
Although switched and full-duplex Ethernet—and segmentation—improve overall net-
work performance, these implementation strategies for enhancing 10-Mbps Ethernet per-
formance do not actually increase data transmission rates, that is, they do not speed up the
network. To address this issue of speeding up the network, IEEE increased Ethernet/802.3’s
10-Mbps data transmission rate, ﬁrst to 100 Mbps, then to 1000 Mbps, and in the very near
future, to 10,000-Mbps Ethernet. This strategy of speeding up the network is different from
the 10-Mbps Ethernet strategies discussed earlier and can be best understood by viewing
a network as a crowded highway. A strategy that employs segmentation, switched Ethernet,
or full-duplex Ethernet adds more lanes to the highway. A 100-Mbps, 1000-Mbps, or
10,000-Mbps technology, however, actually increases the speed limit of the highway by
orders of magnitude, from 10 Mbps to 100 Mbps to 1000 Mbps to 10,000 Mbps.
43. Why do we need to increase the speed of the LAN?
There are several reasons. First, the introduction of more sophisticated operating sys-
tems and applications, faster processors, and greater disk and memory capacities, has led
to a pronounced degradation in overall network and application performance. Second,
many companies now use Internet technologies to build private, corporate intranets that
rely on standard web browsers such as Netscape’s Communicator and Microsoft’s Internet
Explorer to provide employees with access to critical corporate data. These web browsers
are capable of supporting bandwidth-intensive rich media data types, including high-reso-
lution graphics, 3D imaging, audio, video, and voice. Third, the introduction of multime-
dia client/server applications, the deployment of network computers and Java-based
servers, and an increasing number of network users, are taxing ﬁrst-generation Ethernet.
44. What’s the history of 100-Mbps Ethernet?
The concept of 100 Mbps Ethernet was ﬁrst introduced in 1992. By August 1993, the
Fast Ethernet Alliance (FEA) was formed. Within two years, membership grew to more
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