Technical data

Glossary • 335
WAGO-I/O-SYSTEM 750
BACnet/IP Controller
Bridge
A bridge runs on Layer 2 of the ISO/OSI model. Although the bridge corre-
sponds to a Switch, it has only one output, however.
Bridges separate the network into Segments, allowing the number of nodes
to be increased. Corrupt data is filtered out. Telegrams are then sent when
the target address is located in the linked Segment. Only the frame of the
MAC layer is treated. If the destination address is known, the bridge then
forwards the data (when the destination address is on a different string than
the one where the Frame originated), or destroys it (subscriber already has
the frame). If you do not know the address, the bridge forwards the data in
all its known Segments and notes the source address.
A bridge is used to transfer messages independently of the message destina-
tion.
Broadband
Transmission technique using a high bandwidth to permit high data transfer
rates. This technique allows several devices to transmit simultaneously.
Opposite: Baseband
Broadcast
Broadcast. A message that is sent to all stations connected to the network.
Bus
Bus is a general designation for a line used for bit-parallel or bit-serial data
transfer. The bus consists of address, data, control and supply bus. The width
of the bus (8, 16, 32, 64-bit) and its frequency are the determining factors for
the data transmission rate. The width of the address bus limits network ex-
pansion. The fieldbus is a special type of serial bus.
Byte (Binary Yoked Transfer Element)
A data element larger than a bit and smaller than a word. A byte generally
contains 8 bits. A byte may contain 9 bits in 36-bit computers.
C
Client
Service-requesting device within the Client Server System. With the aid of
the service request, the client can access objects (data) on the Server. The
service is provided by the server.