The SDLC Link subentity instance exists for each physical line and manages all stations on the line.
1 – create
create sdlc link
The create sdlc link command creates an instance of the SDLC Link
subentity for each physical line, which manages all stations on the
line. Creation also allocates resources for the subentity, and set
its characteristics to their default values.
Ex, ncl> create sdlc link sdlc-1 line modem connect line line-0, -
_ncl> capability primary
1.1 – Characteristics
Line local entity Specifies the Modem Connect Line on
name which the SDLC protocol operates.
For more information about Modem
Connect Line refer to the
DECnet-Plus Network Control
Language Reference.
Capability primary | Specifies the capability of the
secondary | Station subentities of this Link
negotiable entity. Negotiable stations can
become either primary or secondary.
The default is negotiable.
Configuration pointtopoint | Specifies whether the Link supports
multipoint only a point-to-point connection or
can also support a multipoint
connection. Multipoint supports one
or more than one connection. The
default is pointtopoint. The Peer
Server does not support multipoint
primary connections.
Connection nonswitched | Specifies whether the Link supports
Type switched switched or nonswitched connections.
The default is nonswitched.
Receive (1-32764) Specifies the maximum frame size
Frame Size (excluding the header) that can be
received on the line represented by
this Link. The default is 1000.
Reply Timer (100-60000) Specifies the time (in milliseconds)
to wait for an acknowledgment before
starting the recovery procedure. The
default is 3000.
Retry (0-128) Specifies that, when the Link is
Maximum secondary, this is the maximum
number of times a frame is
retransmitted before assuming a
fatal error. When the Link is
primary, this is the number of times
that a retry will be attempted. The
default is 15.
Poll Pause (0-60000) The time in milliseconds to pause
when the end of the polling list is
reached. Used only when the Link is
primary. The default is 200.
Service (1-255) Specifies the maximum number of
Limit regular scans of the service order
table for secondary Stations that
will be made before a special scan
is made. Used when the Link is
multipoint primary. The default is
4. Not used at this time.
TWA Send no | yes Specifies whether the Link provides
Priority priority for outbound services when
configured for Two-Way Alternating
(half-duplex) data transfer in the
multipoint primary mode. Yes
means that PIUs that arrive for
transmission while data is being re-
ceived are transmitted immediately.
No, the default, means that outbound
transmission is strictly determined
by the position of station service
order entries in the Service Order
Table. This attribute is not
relevant to SDLC point-to-point
operations. Not used at this time.
2 – delete
delete sdlc link The delete sdlc link command deletes an instance of the SDLC Link subentity and deallocates resources for the subentity. The Link subentity must be in the off state and must have no Station subentities. Ex, ncl> delete sdlc link sdlc-0
3 – disable
disable sdlc link The disable sdlc link command disables an instance of the SDLC Link subentity. You can only disable a previously enabled entity. The disable command stops the operation of the Link subentity. To be successful with this command, all Station subentities on the Link must have been disabled. At the completion of the command the subentity is off. Ex, ncl> disable sdlc link sdlc-0
4 – enable
enable sdlc link The enable sdlc link command places the SDLC Link subentity in its enabled state (on). An association may be made between the Link subentity and the Modem Connect Line entity of the physical line on which the protocol operates. For more information about Modem Connect Line refer to the DECnet-Plus Network Control Language Reference. Ex, ncl> enable sdlc link sdlc-0
5 – set
set sdlc link The set sdlc link command let you set the attributes for the SDLC Link subentity. The SDLC Link subentity defines the data link attributes that are shared by its Station subentities. Ex, ncl> set sdlc link sdlc-0 capability = primary
5.1 – Characteristics
Line local entity Specifies the Modem Connect Line on
name which the SDLC protocol operates.
This attribute is settable only
when the Link is disabled. For
more information about Modem
Connect Line refer to the
DECnet-Plus Network Control Language
Reference.
Capability primary | Specifies the capability of the
secondary | Station subentities of this Link
negotiable entity. Negotiable stations can
become either primary or secondary.
This attribute is settable only when
the Link is disabled. The default is
negotiable.
Configuration pointtopoint | Specifies whether the Link supports
multipoint only a point-to-point connection or
can also support a multipoint
connection. Multipoint supports one
or more than one connection. This
attribute is settable only when the
Link is disabled. The default is
pointtopoint. The Peer Server does
not support multipoint primary
connections.
Connection nonswitched | Specifies whether the Link supports
Type switched switched or nonswitched connections.
This attribute is settable only when
the Link is disabled. The default is
nonswitched.
Receive (1-32764) Specifies the maximum frame size
Frame (excluding the header) that can be
Size received on the line represented by
this Link. This attribute is settable
only when the Link is disabled. The
default is 1000.
Reply Timer (100-60000) Specifies the time (in milliseconds)
to wait for an acknowledgment before
starting the recovery procedure. The
default is 3000.
Retry (0-128) Specifies that, when the Link is
Maximum secondary, this is the maximum
number of times a frame is
retransmitted before assuming a
fatal error. When the Link is
primary, this is the number of times
that a retry will be tried. This
attribute is settable only when the
Link is disabled. The default is 15.
Poll Pause (0-60000) The time in milliseconds to pause
when the end of the polling list is
reached. Used only when the Link is
primary. The default is 200.
Service (1-255) Specifies the maximum number of
Limit regular scans of the Service Order
Table for secondary Stations that
will be made before a special scan
is made. Used when the Link is
primary. Is settable only when the
Link is disabled. The default is 4.
Not used at this time.
TWA Send no | yes Specifies whether the Link provides
Priority priority for outbound services when
configured for Two-Way Alternating
(half-duplex) data transfer in the
multipoint primary mode. Yes
means that PIUs that arrive for
transmission while data is being
received are transmitted immediately.
No, the default, means that outbound
transmission is strictly determined
by the position of station service
order entries in the service order
table.
This attribute is not relevant to
SDLC point-to-point operations. This
attribute is settable only when the
Link is disabled. Not used at this
time.
6 – show
show sdlc link The show sdlc link command displays the values of the attributes for the SDLC Link subentity. The SDLC Link subentity defines the data link attributes that are shared by its Station subentities. Ex, ncl> show sdlc link sdlc-0 all status
6.1 – Identifier
Name A Simplename that is unique among the SDLC Link
entities maintained by the SDLC module. The network
manager specifies Name when the Link is created.
6.2 – Status
UID Displays the entity's unique identifier, which is
generated when the the entity is created.
State Displays the operational state of this SDLC Link
subentity. Possible states are
Inoperable The Link cannot be enabled.
Off You have issued a disable command for
this Link. The Link is in the
inactive or pending inactive state.
On You have issued an enable command for
this Link.
Role Displays the role this Link has taken. Values for
Role are:
Idle No role has been assumed yet.
Primary The role is that of a primary Link.
Secondary The role is that of a secondary Link.
6.3 – Characteristics
Line local entity Displays the Modem Connect Line on
name which the SDLC protocol operates.
You must specify a value in
order to enable the link. For more
information about Modem Connect
Line refer to the DECnet-Plus
Network Control Language Reference.
Capability primary | Displays the capability of the
secondary | Station subentities of this Link
negotiable entity. Negotiable stations can
become either primary or secondary.
The default is negotiable.
Configuration pointtopoint | Displays whether the Link supports
multipoint only a point-to-point connection or
can also support a multipoint
connection. Multipoint supports one
or more than one connection. The
default is pointtopoint. The Peer
Server does not support multipoint
primary connections.
Connection nonswitched | Displays whether the Link supports
Type switched switched or nonswitched connections.
The default is nonswitched.
Receive (1-32764) Displays the maximum frame size
Frame (excluding the header) that can be
Size received on the line represented by
this Link. The default is 1000.
Reply Timer (100-60000) Displays the time (in milliseconds)
to wait for an acknowledgment before
starting the recovery procedure. The
default is 3000.
Retry (0-128) Displays that, when the Link is
Maximum secondary, this is the maximum
number of times a frame is
retransmitted before assuming a
fatal error. When the Link is
primary, this is the number of times
that a retry will be tried. The
default is 15.
Poll Pause (0-60000) Displays the time in milliseconds to
pause when the end of the polling
list is reached. Used only when the
link is primary. The default is 200.
Service (1-255) Displays the maximum number of
Limit regular scans of the Service Order
Table for secondary Stations that
will be made before a special scan
is made. Used when the Link is
primary. The default is 4. Not
used at this time.
TWA Send no | yes Displays whether the Link provides
Priority priority for outbound services when
configured for Two-Way Alternating
(half-duplex) data transfer in the
multipoint primary mode. Yes
means that PIUs that arrive for
transmission while data is being
received are transmitted immediately.
No, the default, means that outbound
transmission is strictly determined
by the position of station service
order entries in the service order
table.
This attribute is not relevant to
SDLC point-to-point operations. Not
used at this time.
6.4 – Counters
Group Polls The number of unnumbered group polls received on
this link.
Frame Receive The number of times the physical layer encountered
Errors an error trying to receive a frame.
Underlying The number of times the Link's underlying Line was
Lines deleted after the Link had established a connection
Deleted to it.
Creation Time The time that the SDLC Link subentity was created.