Cabletron Systems LR-2000 User Manual - page 9
Page 2 - 2
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.3 SPECIFICATIONS
This section contains the specifications for the Cabletron Systems LR-2000 Local
Repeater. Cabletron Systems reserves the right to change these specifications at any time
without notice.
GENERAL
Delay Times: (any segment in to all segments out)
Parameter:
Typical
Worst
Value
Case
Start of Packet:
500 ns
600 ns
Collision to JAM:
Receive Mode
200 ns
300 ns
Transmit Mode
500 ns
625 ns
Preamble:
Input:
Minimum of 20 bits required.
Output:
64 bits min. (last 2 bits are 1, 1).
JAM output:
A pattern of 1, 0 is sent to one or both of the
segments if a collision occurs.
Fragment Extension:
Any packet less than 96 bits long. (Packet
fragments are extended using the JAM [1, 0]
data pattern).
FAULT Protection:
Each segment will disconnect itself from the other
segment if 32 consecutive collisions occur, or if the
collision detector of a segment is on for longer than
approximately 2.4 ms. This FAULT protection will
reset automatically after one packet is transmitted
onto the FAULT protected segment without
causing a collision.
LANVIEW LEDs
PWR
Indicates that the LR-2000 is receiving power.
XCVR PWR
Indicates that the LR-2000 is providing power to
the transceivers connected to it.
JAM
Indicates that the LR-2000 is propagating a
collision on one segment to the other segment
connected to the repeater.