Frame relay frame size and fragmentation, Monitored events count, Polling verification time – Visara LINCS Configuration User Manual
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LINCS Configuration
707023-003
If this field is set to the maximum value (4119), no fragmentation will occur at the Frame
Relay layer and frame size will be determined by the value entered in the link profile.
SNA over frame relay also has special considerations for frame size.
Frame Relay Frame Size and Fragmentation
The maximum reassembled received SNA frame size is 4105 (including TH, RH, and
RU).
Maximum SNA frame sizes prior to fragmentation may be configured via the link profile
associated with the given host, gateway, or APPN circuit. SNA data will be segmented according
to the size specified in the link profile.
If transmit fragmentation is not desired, the max frame size configured in the link profile
should be set to a value at least 14 bytes (the size of Frame Relay header, LLC header and
FCS) less than the maximum Frame Relay transmit size configured on the line panel. Maximum
performance is achieved by configuring frame sizes such that fragmentation and segmentation
are not required.
The following table lists the LLC max frame size (configured on the link profile panel) and
the Frame Relay frame size (configured on the Frame Relay line panel) required to transport
common SNA RU sizes without Frame Relay fragmentation or SNA segmentation:
e
z
i
S
U
R
A
N
S
e
z
i
S
e
m
a
r
F
t
i
m
s
n
a
r
T
x
a
M
C
L
L
t
i
m
s
n
a
r
T
x
a
M
y
a
l
e
R
e
m
a
r
F
e
z
i
S
e
m
a
r
F
6
5
2
5
6
2
9
7
2
1
5
1
2
5
5
3
8
6
7
7
7
7
1
9
4
2
0
1
3
3
0
1
7
4
0
1
6
3
5
1
5
4
5
1
9
5
5
1
8
4
0
2
7
5
0
2
1
7
0
2
Monitored Events Count
The Monitored Events Count (N393) data entry field determines the size of the measurement
interval used by N392.
Valid entries range from 1 to 10. The default is 4.
LINCS will verify that N393 is greater than or equal to N392.
Polling Verification Time
The Polling Verification Timer (T392) toggle field defines the expected frequency with which
LMI Status Enquiry messages are received. This timer should be set to a value greater than
the T391 timer configured on the user FRTE.
Toggle choices are 5, 10, 15, 20, 25 and 30. The default is 15 seconds.