Here is the description of ethernet and token ring

1. ETHERNET

2. •Ethernet is the most widely-installed local area
network ( LAN) technology.
•Specified in a standard, IEEE 802.3, Ethernet was
originally developed by Xerox from an earlier
specification called Alohanet and then developed
further by Xerox, DEC, and Intel.
•An Ethernet LAN typically uses coaxial cable or
special grades of twisted pair wires.
•The most commonly installed Ethernet systems are
called 10BASE-T and provide transmission speeds up
to 10 Mbps

3. •The Fast Ethernet standard (IEEE 802.3u) has
been established for Ethernet networks that
need higher transmission speeds.
•This standard raises the Ethernet speed limit
from 10 Mbps to 100 Mbps with only minimal
changes to the existing cable structure.
•Fast Ethernet provides faster throughput for
video, multimedia, graphics, Internet surfing
and stronger error detection and correction.

4. •Gigabit Ethernet was developed to meet the need
for faster communication networks with
applications such as multimedia
•The most important differences between Gigabit
Ethernet and Fast Ethernet include the
additional support of full duplex operation in
the MAC layer and the data rates.

5. •10 Gigabit Ethernet is the fastest and
most recent of the Ethernet standards.
IEEE 802.3ae defines a version of Ethernet
with a nominal rate of 10Gbits/s that
makes it 10 times faster than Gigabit
Ethernet.

8. A Token Ring network is a local area network (LAN) in
which all computers are connected in a ring or star
topology and a bit- or token-passing scheme is used in
order to prevent the collision of data between two
computers that want to send messages at the same time.
The Token Ring protocol is the second most widely-used
protocol on local area networks after Ethernet. The
IBM Token Ring protocol led to a standard version,
specified as IEEE 802.5. Both protocols are used and
are very similar. The IEEE 802.5 Token Ring technology
provides for data transfer rates of either 4 or 16
megabits per second.

9. Very briefly, here is how it works:
•Empty information frames are continuously
circulated on the ring.
•When a computer has a message to send, it
inserts a token in an empty frame (this may
consist of simply changing a 0 to a 1 in the
token bit part of the frame) and inserts a
message and a destination identifier in the
frame.

10. •The frame is then examined by each successive
workstation. If the workstation sees that it is the
destination for the message, it copies the
message from the frame and changes the token
back to 0.
•When the frame gets back to the originator, it
sees that the token has been changed to 0 and
that the message has been copied and received.
It removes the message from the frame.

11. •The frame continues to circulate as an "empty"
frame, ready to be taken by a workstation when it
has a message to send.
•The token scheme can also be used with bus
topology LANs.

15. •Fiber channel is the general name of an
integrated set of standards being developed by
the American National Standards Institute (ANSI).
• The fiber channel standard defines a high-speed
data transfer interface that can be used to
connect workstations, mainframes, supercomputers,
storage devices, and displays.
•The fiber channel standard addresses the need for
very fast transfers (up to 1 gigabit per second)
of large amounts of information.
• Currently, fiber channel's main use is as an
interface to storage.