Cabletron Systems Netlink FRX8000, User Manual

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Configuring X.25 9-7
T2 Acknowledgment Delay
is X.25 timer
T2
, the length of time the node will delay acknowledgment of a received
I-frame if there is no outgoing I-frame to be sent. If during this period the node
receives an I-frame for transmission, the acknowledgment will be sent with it, and the
delay timer will be reset.
T3 Link Assurance Period
is X.25 timer
T3
, the length of time after which the logical DCE will poll its coun-
terpart if there is no data transfer. The value should be sufficiently larger than the
DCE's
T1
timer (Retransmission Period), to assure that the link is not operational
before a poll is sent.
Logical DCE
Selecting
N
defines the port as logical DTE. The other end of the connection must be
the opposite of this port. Logical DCE/DTE is independent of physical—either can be
either. A node connecting a subscriber device into a network should normally be con-
figured as logical DCE.
Generate Clock
If this port is a physical DCE (determined by LP jumpers and/or cable/converter
interface), specify
Y
, since DCE generates clock. If the port is DTE, specify
N
.
Rcv Clock (TT) from DTE
allows the clock to be looped back from the DTE using the TT (Terminal Timing)
signal, which can be helpful on high-speed ports.
Mask Link Alarms
determines whether an alarm (see Chapter 21 ) will be generated if the link goes up or
down. If
Mask Link Alarms
is
Y
, these alarms will not be generated.
Level 3/7000 Parameters
Lowest/HighestIncoming/Two-Way/Outgoing Channel
are the ranges of logical channel numbers that subscribers can use for calls through
this port. The valid values for each parameter that is used are determined as follows:
Channel Valid Values
Lowest Incoming 1
through
Highest Incoming
Highest Incoming
Greater than/equal to
Lowest Incoming
Lowest 2-Way
Greater than
Highest Incoming
Highest 2-Way
Greater than/equal to
Lowest 2-Way
Lowest Outgoing
Greater than
Highest 2-Way
Highest Outgoing Lowest Outgoing
through
4095
Changing any parameter to a value that violates this order automatically changes any
other values now in violation, specifying the first value(s) within the valid range. If
any pair is not used, its constraints apply to the next higher or lower pair (whichever
is appropriate) in the above list.
Flow Control Negotiation
is an optional X.25 facility that permits negotiation of the flow control parameters
(packet and window sizes for either direction of data transmission) on a per call basis.
If
N
is selected, the default packet and window sizes will be used. If
Y
is selected, a
packet and/or window size included in a call packet, up to the Maximum Packet Size
and/or Maximum Window Size configured in this Port record, will be used. (If either
is not included, the default for that parameter will be used.)