Specifications

10BASE5 Ethernet Network Design
7-6 Ethernet Network Design
Multiple Segment 10BASE5 Ethernet Network
We have seen how we can build a single segment 10BASE5 Ethernet
network. This is adequate if we only want to span a distance of 500 m. If it
is necessary to cover a greater area or to add additional coaxial taps
beyond the 100 tap limit, more coaxial cable must be added. To connect the
new coaxial segment to the existing backbone, a repeater must be used.
As you recall from Chapter 6, Ethernet Devices, the repeater is a Physical
Layer device that has the capability to forward frames at up to full
Ethernet bandwidth. It regenerates the preamble and amplifies and
retimes the signal from one backbone cable to another. It is connected to
the coaxial cable through transceivers in the same fashion as any other
node on the network and requires external power to operate. The repeater
also extends fragmented frames and will auto-partition ports in the event
of excess collisions.
Repeater Use
When a local repeater is used to connect two 10BASE5 coaxial segments,
each segment may be a maximum of 500 m in length with up to 100 taps,
including taps made to connect the repeater. The maximum of 1,024
devices allowed and the AUI cable length limitation of 50 m apply to both
segments. It is not necessary that repeaters be connected at the ends of the
coaxial segment. Refer to Figure 7-6.
Figure 7-6. Repeater Use
Network Segment 1
(Up to 1,024 devices)
Network Segment 2
(Up to 1,024 devices)
Repeater
1913-23