Transition Networks E-PSW-TX-02 The 5-Segment Rule 10BASE-T, Auto-Negotiation, Pocket Switch

Installing Network Cable (continued)

The 5-Segment Rule (10BASE-T)

The Ethernet 10BASE-T 5-segment rule defines a segment as the cable connection between station interfaces. The transmission path between any two terminal devices in the same collision domain can consist of no more than five segments. Installing the Transition Networks’ pocket switch in the network separates collision domains, so the 10BASE-T 5- segment rule applies separately to each collision domain.

The Transition Networks pocket switch can be installed to provide one 10BASE-T switched port and one 100BASE-TX switched port.

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Install Transition Networks' Pocket Switch To Connect Legacy Ethernet to Fast Ethernet

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Auto-Negotiation

ASSIGNING SEGMENT NUMBERS

To assign segment numbers to cable connections:

1.Determine the network device separated from the Transition Networks’ pocket switch by the greatest number of segments.

2.Define a segment path between that network device and the Transition Networks’ pocket switch by labeling the cable connection to the Transition Networks’ pocket switch “segment

1” and numbering each segment in the path to the terminal up to “segment n” (n = total number of segments ≤ 5).

3.Verify that no segment path in the collision domain contains more than n ≤ 5 segments.

4.Repeat steps 1-3 for next collision domain.

17 Transition Networks’

The 100BASE-TX standard includes automatic speed and duplex mode sensing as part of the Auto-Negotiation function. When two Auto- Negotiation devices with multiple capabilities are connected together, they find their highest performance mode of operation based on a priority`table. The Auto-Negotiation protocol contains a set of priorities which result in the devices selecting their highest common set of abilities. (The process happens out of band, with no loss of network throughput.) Each 100BASE-TX station sends a burst of link integrity test pulses, called a fast link pulse (FLP), generated automatically. If the receiving switch is capable of 10BASE-T communication only, the FLPs are ignored and the cable segment operates as 10BASE-T. If the switch can support 100BASE-TX operation, the switch detects the FLPs, uses the Auto-Negotiation algorithm and FLP data to determine the highest possible cable segment speed and mode, and automatically places both the station and the switch into 100BASE-TX mode.

Pocket Switch 10