OSI/TS Configuration and Management Manual

Managing a Transport Connection
OSI/TS Configuration and Management Manual—424831-001
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Connection-Initiation Failure
The class in the response must have the same multiplexing capabilities as the requested
class. If the transport protocol is operating over a local area subnetwork, OSI/TS
accepts only class 4 in the response.
Expedited Data
If the connection request asks for transport-expedited data and the responder rejects it,
OSI/TS does not use expedited data. If the connection request did not ask for expedited
data, the responder cannot.
TPDU Size
If the CC-TPDU contains a value for this parameter that is less than the value sent in the
CR-TPDU, OSI/TS uses the lesser value for the connection. The protocol does not
permit a greater value in the CC-TPDU.
Connection-Initiation Failure
If OSI/TS does not receive a CC-TPDU in response to a CR-TPDU, the connection
request is considered to have failed. This can occur in one of the following two ways:
•
Time out
•
Remote disconnect
Time Out
After sending a CR-TPDU, OSI/TS starts the timer CONNECTTIMEOUT (for classes 0
through 3) or the timer REXMITTIMEOUT (for class 4). You can set the values of
these timers using SCF.
When OSI/TS is operating over connection-mode network service and the timer expires
before a valid CC-TPDU is received, OSI/TS issues a network disconnect (N-DISC) if
no other transport connections are multiplexed onto the subnetwork connection. OSI/TS
does not issue a network reset (N-RESET).
Over connectionless network service, OSI/TS retransmits the CR-TPDU up to
MAXREXMIT times. If it does not receive a valid CC-TPDU before the timer
(CONNECTTIMEOUT or REXMITTIMEOUT) expires, the connection fails.
Remote Disconnect
If OSI/TS receives a DR-TPDU or an ER-TPDU from the remote peer, it releases the
connection request.
Connection Establishment: OSI/TS as Responder
OSI/TS responds to a valid CR-TPDU from a remote transport peer entity only if a local
transport user has indicated that it can accept connections. To initialize the OSI/TS
subsystem as a connection-establishment responder, an application sends a file-system
message that allows OSI/TS to respond to valid incoming CR-TPDUs. Thus, transport