Cabletron Systems Netlink FRX8000, User Manual

Page: 124 / 468

9-6 FRX8000 3. 0 User G uide, Rev 02
Line Speed Code
specifies the data transmission rate in bits per second, and the clock speed when the
port is a physical DCE. If this port is not configured to generate clock, specify the line
speed that corresponds (as closely as possible) to the configuration of the device con-
nected to the port. Line speed codes are as follows. (Some speeds have two corre-
sponding codes because they are defined in different parts of the software. Either code
can be specified.)
3
= 75
4
= 150
5
= 300
6
= 600
7
= 1200
8
= 2400
9
= 4800
10
= 9600
11
= 19.2K
12
= 48K
13
= 56K
14
= 64K
15
= 72K
16
= 112K
17
= 128K
18
= 224K
19
= 256K
20
= 14.4K
21
= 24K
22
= 28.8K
23
= 38.4K
24
= 56K
25
= 112K
26
= 168K
27
= 224K
28
= 280K
29
= 336K
30
= 392K
31
= 448K
32
= 504K
33
= 560K
34
= 616K
35
= 672K
36
= 728K
37
= 784K
38
= 840K
39
= 896K
40
= 952K
41
= 1.008M
42
= 1.064M
43
= 1.12M
44
= 1.176M
45
= 1.232M
46
= 1.288M
47
= 1.344M
48
= 1.4M
49
= 1.456M
50
= 1.512M
51
= 1.568M
52
= 1.624M
53
= 1.68M
54
= 64K
55
= 128K
56
= 192K
57
= 256K
58
= 320K
59
= 384K
60
= 448K
61
= 512K
62
= 576K
63
= 640K
64
= 704K
65
= 768K
66
= 832K
67
= 896K
68
= 960K
69
= 1.024M
70
= 1.088M
71
= 1.152M
72
= 1.216M
73
= 1.28M
74
= 1.344M
75
= 1.408M
76
= 1.472M
77
= 1.536M
78
= 1.6M
79
= 1.664M
80
= 1.792M
81
= 1.728M
82
= 1.856M
83
= 1.92M
84
= 1.984M
85
= 2.048M
The maximum for an RS-232 interface on an N7400 or 7500 is 19.2K. The
maximum for an RS-232 interface on an FRX8000 is 64K if the port is
directly connected to the user device via the 5-foot Cabletron RS-232
cable. If modems or longer cabling are used, the recommended maximum
speed is 19.2K. (The EIA RS-232 standard applies to line speeds of 19.2K
and lower.)
Modulus
is a number for values used in X.25 level-2 sequenced packets. The actual frame num-
bering is 0–7 for modulus 8 and 0–127 for modulus 128.
Outstanding Frames
is X.25 value
K
, the maximum number of sequentially numbered I-frames that can be
waiting for acknowledgment. If this number is exceeded, no more frames will be
transmitted until an acknowledgment is received.
N2 Maximum Retransmissions
is X.25 value
N2
, the maximum number of times the node will attempt to send an I-
frame after a Retransmission Period expiration. A larger value for this parameter
increases the probability of an eventual correct transfer between DTE and DCE, but a
smaller value permits faster detection of a permanent error condition.
T1 Retransmission Period
is X.25 timer
T1
, the length of time before the node will transmit an I-frame if the pre-
vious transmission is not acknowledged. If the period expires, the timer will be reset
and a supervisory frame will be transmitted demanding immediate acknowledgment.
The
N2
(see that entry, above) counter will also be incremented.
The default value of
2000 ms
allows avoidance of unnecessary retransmission of
frames that have merely been delayed.