Classification Of Repeaters; Class I Repeaters - 3Com 100 TX User Manual

Classification of
Repeaters

Class I Repeaters

100 meters maximum
(160.8 meters: fiber cable)
The IEEE 802.3 standard defines two classes of repeaters for 100BASE-T
Fast Ethernet networks, as detailed below.
A Class I repeater is a hub with internal delay such that only one repeater can
exist between any two DTE (data terminal equipment) devices within a single
collision domain when two maximum-length cable segments are used.
The LinkBuilder FMS 100-TX Hub (product number 3C250-TX/1) is a Class I
device only.
Internal delay is the time delay between the sensing of the first data bit
received and the sensing of the first bit transmitted on a 100 Mbps CSMA/CD
network. Propagation time delays also affect repeater classification. Class I
repeater delays are longer than Class II repeater delays.
A Class I network topology consists of one hub (or hub stack) in a single collision
domain existing between any two end stations. The stack of LinkBuilder FMS
100-TX Hubs in this configuration can contain up to eight hubs.
Figure 3-8 shows a single collision domain containing one Class I hub stack
between two end stations, with the distance between end stations being
200 meters. If one of the hub-to-node segments is implemented with fiber
cabling (by using the 100BASE-FX transceiver interface module), the total
span can be 260.8 meters. That is, up to 100 meters can consist of UTP
cabling, with up to 160.8 meters of fiber cabling.
200 meters: maximum UTP distance
(260.8 meters: mixed UTP and fiber cable)
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
100BT
1x 1x 1x 1x 1x 1x 1x 1x
Class I configuration
Figure 3-8 Class I Hub
Classification of Repeaters
100 meters maximum
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
LinkBuilder
STATUS UNIT 3C12345 ® R EPEATER
1x 1x 1x 1x ACTIVITY FAN FAIL CLS2
LINE OVERTEMP CLS1
PARTITION COLLISION PWR
1 2 3 4 5 6 7 8 9 10 11 12 13
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