HPE FlexNetwork MSR series Configuration Manual page 233

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ITU-T Q.933 Annex A.
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ANSI T1.617 Annex D.
•
Nonstandard LMI (compatible with other vendors).
To communicate properly, the DTE and the DCE must use the same type of LMI.
LMI messages
LMI messages include the following types:
•
Status enquiry message—A DTE sends status enquiry messages regularly to a DCE to
request the status of individual PVCs or verify the link integrity.
•
Status message—When a DCE receiving a status enquiry message, the DCE responds with a
status message. The status message is used to transmit the PVC status or verify the link
integrity.
Status enquiry messages and status messages include the following types:
•
Full status—Verifies the link integrity and transmits the PVC status.
•
Link integrity verification (LIV)—Verifies the link integrity.
LMI negotiation parameters
Table 7 lists the parameters ITU-T Q.933 Annex A uses for message exchange. You can configure
these parameters to optimize device performance.
Table 7 LMI negotiation parameters
Device
role
DTE
DCE
How LMI works
LMI works in the following process:
Value
Timer/counter
range
Full status polling
1 to 255
counter (N391)
Error threshold
1 to 10
counter (N392)
Monitored events
1 to 10
counter (N393)
0 to 32767
Keepalive (link
integrity verification
0
polling) timer
LMI
(T391)
disabled.
Error threshold
1 to 10
counter (N392)
Monitored events
1 to 10
count (N393)
Keepalive (polling
verification) timer 5 to 30
(T392)
Default
Description
value
Sets the ratio of link integrity request
6 messages sent to full status enquiry messages
sent. The ratio is (N391-1):1.
Sets the number of errors required for LMI to
3 declare a link dead, within the event count
specified by N393.
Sets the monitored event count. If the number
of errors within the N393 status enquiry
4
messages reaches N392, a DTE considers
that the error threshold is reached.
Sets the interval (in seconds) at which a DTE
sends a status enquiry message. An error is
means
10
recorded if the DTE has not received any
replies when the timer expires.
Sets the number of errors required for LMI to
3 declare a link dead, within the event count
specified by N393.
Sets the monitored event count. If the number
of errors within the N393 status enquiry
4
messages reaches N392, a DCE considers
that the error threshold is reached.
Sets the interval (in seconds) for receiving a
status enquiry message. If a DCE has not
15
received any status enquiry messages when
the timer expires, an error is recorded.
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