Cabletron Systems SEH-22 - Manual (Page 18)

OPERATING SPECIFICATIONS
SEH USER’S GUIDE 2-5
2.4 OPERATING SPECIFICATIONS
This section describes the operating specifications for the SEH. Cabletron
Systems reserves the right to change these specifications at any time
without notice.
General
Delay Times (Start of Packets):
Twisted Pair to EPIM- A 1.10
µ
s
Twisted Pair to Twisted Pair 1.00
µ
s
EPIM-A to Twisted Pair 1.00
µ
s
Delay Times (JAM):
Twisted Pair to EPIM-A 960 ns
Preamble:
Input: Minimum of 40 bits required
Output: 64 bits min. (last 2 bits are 1, 1)
JAM Output:
Collisions are propagated through
the network using the JAM signal
of an alternating pattern of 1’s and
0’s in accordance with 802.3
specifications for a repeater unit.
Fragment Extension:
Packet fragments are extended to a
minimum of 96 bits using the JAM
[1, 0].
SEH Book Page 5 Tuesday, March 19, 1996 4:12 PM