Specifications

RADring
Installation & Operation Manual Functional Description
3/11/98 12:33 RADring Functional Description - Ethernet 2-9
2.4 General Ethernet
Logical Topology
In an Ethernet LAN, computers Ethernet devices and stations are connected
to a segment. The data signal is transmitted from one station to the others
via a star connection. Each station transmits in accordance with its
independent 10MHz clock.
A node starts to transmit data when it detects that no other node is
transmitting. Transmission is ceased when the node detects that another
station transmits on the LAN (collision). After a collision, the node waits for a
random period of time and then tries to transmit again. The mechanism
described above ensures that only up to one valid frame is transmitted at any
given moment.
Physical Topology
Stations are connected to the star by hubs containing multi port repeaters
(see Figure 2-9). This topology allows central connections and management
of the cabling. The hub checks the link integrity of the station prior to
inserting it into the segment.
In normal operation the station is connected to the segment. The station is
automatically disabled when the link integrity fails or when the station
repeatedly breaks the access rules of the LAN.
Segment Physical
Limitations
The maximum delay between each two nodes is the time of 576 bits
(57.6 µsec). The delay calculation comprises the cables delay and the
devices between the nodes delay.
The maximum number of hubs (repeaters) between each two nodes is four.
IRL
IRLIRL
Figure 2-9 Ethernet Physical Connection of RADrings