MCSE : Security Specialist
802.5 (token ring)
The
IEEE 802.5 Token Ring standards define services for the OSI physical
layer and the MAC sublayer of the data link layer. Token Ring
computers are situated on a continuous network loop. A Token Ring
controls access to the network by passing a token, from one computer
to the next. Before they can transmit data they must wait for a free
token, thus token passing does not allow two or more computers to
begin transmitting at the same time.
Token Ring
Media
|
MAC Method
|
Signal Propagation Method
|
Speed
|
Topologies
|
Maximum Connections
|
Twisted-pair (various types) |
Token passing |
Forwarded from device to device (or port to port on a hub)
in a closed loop |
4 Mbps
16 Mbps |
Ring
Star-using Token Ring repeater hubs |
255 nodes per segment |
802.11b (wireless)
802.11b is a wireless Ethernet technology operating at 11MB. 802.11b
devices use Direct Sequence Spread Spectrum (DSSS) radio technology
operating in the 2.4GHz frequency band.
An
802.11b wireless network consists of wireless NICs and access
points. Access points act as wireless hubs to link multiple wireless
NICs into a single subnet. Access points also have at least one
fixed Ethernet port to allow the wireless network to be bridged to a
traditional wired Ethernet network.. Wireless and wired devices can
coexist on the same network.
|