NCLHELP.HLB  —  set  ddcmp (OpenVMS VAX), link
    set  [node node-id] ddcmp link link-name ...

    Modifies the attributes of a link to a DDCMP communications port.
    The modifiable attributes and their data types [in brackets] are:

    retransmit timer [integer]
    physical line [local-entity-name]
    receive buffers [integer]

    Refer to attributes for specific command examples, or select
    logical_station to view the settable attributes of the ddcmp
    link logical_station subentity.

1  –  physical_line

    Default: No name       Value: Local entity name

    Name of the Physical layer entity that the link operates over. A
    value for this characteristic must be set before the link entity
    is enabled. You can modify this characteristic only when the
    entity is disabled.

    set [node node-id] ddcmp link link-name -
         physical line local-entity-name

2  –  receive_buffers

    Default: 4             Value: 1-255

    Specifies the number of receive buffers reserved for the link.
    You can only increase the characteristic value.

    set [node node-id] ddcmp link link-name receive buffers integer

    Example:

    set ddcmp link ddcmp-0 receive buffers 8

3  –  retransmit_timer

    Default: 3000          Value: 1-65535

    Maximum time (in milliseconds) to wait between sending a message
    and receiving a valid response. If this time expires, the local
    station takes error recovery action. On full-duplex point-to-
    point links, the timer is started immediately when a message is
    sent.

    set [node node-id] ddcmp link link-name retransmit timer integer

    Example:

    set ddcmp link ddcmp-0 retransmit timer 3000

4  –  logical_station

    set  [node node-id] ddcmp link link-name -
         logical station station-name ...

    Modifies the attributes of a ddcmp link logical station entity
    which manages a link to a remote station.  The modifiable
    attributes and their data types [in brackets] are:

    address [integer]
    babble timer [milliseconds]
    holdback timer [milliseconds]
    transmit window [integer]

    Refer to attributes for specific command examples.

4.1  –  address

    Default: 1             Value: 1-255

    Data link address of the remote station or tributary. You can
    modify this characteristic only when the entity is disabled.

    set [node node-id] ddcmp link link-name -
        logical station station-name -
        address integer

    Example:

    set ddcmp link ddcmp-0 logical station ddcmp-0 address 1

4.2  –  babble_timer

    Default: 6000          Value: 1-65535

    Specifies the time, in milliseconds, for which a selected
    tributary or remote station is allowed to transmit. This
    characteristic is not used on full-duplex links.

    This characteristic is not supported if the characteristic
    protocol of the owning ddcmp link entity is set to tributary.

    set [node node-id] ddcmp link link-name -
        logical station station-name -
        babble timer integer

    Example:

    set ddcmp link ddcmp-0 logical station ddcmp-0 babble timer 6000

4.3  –  holdback_timer

    Default: 0             Value: 0-13000

    Maximum time, in milliseconds, that the local station can delay
    acknowledging a received message if there is no data to send.

    The value of this characteristic is linked to the retransmit
    timer used on the remote station. A suggested value is between
    10% and 20% of that timer. However, the actual values you can use
    may be limited by the communications product.

    The default value indicates that no holdback is used and the
    local station must acknowledge immediately.

    set [node node-id] ddcmp link link-name -
        logical station station-name -
        holdback timer integer

    Example:

    set ddcmp link ddcmp-0 logical station ddcmp-0 -
        holdback timer 0

4.4  –  transmit_window

    Default: 1             Value: 1-255

    Specifies the maximum number of data messages that the local
    station can send without receiving an acknowledgment. This
    characteristic applies only when the remote station is a control
    station or on a half-duplex, point-to-point link. The value of
    this characteristic must be less than or equal to the equivalent
    of the maximum transmit characteristic on the control station or
    remote station.

    set [node node-id] ddcmp link link-name -
        logical station station-name -
        transmit window integer

    Example:

    set ddcmp link ddcmp-0 logical station ddcmp-0 -
        transmit window 127
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