Verilink 9000 Series (34-00271) Product Manual - Manual (Page 231)

Configuration / Operation 209
Device
When connected to a frame relay network, the TXPORT port should be configured
as a Frame Relay Access Device. When two TXPORT units are connected directly,
one unit is a FRAD while the other is configured as a network. A FRAD polls a
NETWORK every T1 Timer seconds with a keep alive status inquiry. The
selections are FRAD and Network.
N1 Counter
This counter indicates the number of keep alive status enquiries that are sent
between full status requests. The selections are 1 to 255, 10.
N2 Counter
The N2 counter specifies the total number of link reliability errors and protocol
errors that can occur during the sliding event monitor count defined by N3. If this
count is exceeded, the port is declared inactive. The selections are 1 to 255, 5.
N3 Counter
This counter represents a Monitored Events Count. For a network, a monitored
event is the receipt of a status enquiry message or the expiration of the polling
verification timer T2. For a FRAD, a monitored event is the transmission of a
status enquiry message. This parameter defines the size of the sliding window that
is used by the TXPORT to determine whether a channel or user device is active.
The selections are 1 to 255, 5.
T1 Timer
This parameter specifies the number of seconds the unit waits between issuing
status enquiry messages. The selections are 1 to 255, 10.
T2 Timer
The T2 timer specifies the maximum amount of time that may elapse between
receipt of status enquiries on a network port. If a status enquiry is not received
within the defined time an error is recorded. The selections are 1 to 255, 15.
Recovery Counter
This parameter is not used.
LMI Standard
This parameter allows the user to select one of the two frame relay standards in
use. When CCITT is selected the LMI (Local Management Interface) uses DLCI
(Data Link Connection Identifier) 1023. When ANSI is selected the LMI uses
DLCI 0. The format of the status response is also slightly different. Selecting
TXPORT allows a standard X.25 protocol analyzer to monitor the link. This
selection can only be used when two MultiPro units are connected directly, with no
intervening public or private frame relay network. Selecting TXPORT does not add
any additional overhead to the protocol and does not effect throughput. The
selections are CCITT, ANSI, and TXPORT.