Specifications

Interfaces
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Function:
Checks the channel to see if maintenance service
is needed.
Applicable only on exclusive maintenance channels.
Inputs:
Channel-id.
- the unique identification of the channel to check.
Outputs:
Return-code
- the status of the request. One of:
Running normally
- the channel is running or attempting to run
normal user traffic.
Maintenance needed
- the channel wants to run maintenance
traffic.
Unrecognized channel
- there is no channel with the specified
identification.
Channel in wrong state
- the channel is not in a state where
the check can be made.
3.1.2 Open
Funct ion:
Opens a port so that the user can transmit and receive frames.
Inputs:
Channel-id
- the unique identification of the channel on which the
port is to be opened.
Pad
- an indication that the data link is to use its own standard
padding technique if padding is necessary. Maintenance operations
use this option, when available, for all but the multiaccess
channel loop protocol.
Id-list
- a list of identification data, such as protocol types or
multicast addresses, that identify this user of the data link.
Data link specific and applicable only on concurrent maintenance
channels. For example, in the Ethernet Data Link this abstract
id-list function
is accomplished using the Ethernet Data Link
Open, Enable-protocol, and Enable-multicast functions.
Outputs:
Return-code
- the status of the request. One of: