DECnet-Plus
Network Control Language Reference

Arguments:

frame	Contents of the header of the received FRMR frame.
frame reject reason	Why the frame was rejected. See possible reasons described under the frame reject reason argument of the frame reject generated event.

link halted

Argument:

link halted reason	Why the protocol halted.
	disc	A DISC frame was received. The remote end has disconnected the link.
	dm	A DM frame was received. The remote end has disconnected the link.
	frmr	A FRMR frame was received. The remote end has detected a frame error.
	implementation specific	The cause is unknown.
	LAN	The LAN station has failed.
	local	Local management action on the sap or link entities has halted the link.
	maximum retry	A PDU had to be retransmitted the maximum number of times without response from the remote end.
	user	Local client action has halted the link.

link initializing

Argument:

link initializing reason

Why the protocol was initialized or reinitialized. See possible reasons described under the link halted reason argument of the link halted event.

link inoperative

link resetting

Argument:

link resetting reason	Why the protocol is being reset.
	frmr	A FRMR frame was received. The remote end has detected a frame error.
	implementation specific	The reason is unknown.
	maximum retry	A PDU had to be retransmitted the maximum number of times without response from the remote end.
	sabme	A SABME frame was received. The remote end has reset the link.

link running

link setup failure

link state changed

For enable:

client data size not supportable

The data size specified by a client that has opened an LLC2 port to use this link cannot be supported.

link data size not supportable

The data size specified by the characteristic maximum data size cannot be supported by the SAP that owns this link.

remote address in use

The remote MAC address and remote link service access point (hex-number LSAP) address are already being used by another link.

The Loopback Application module allows a network manager to invoke a loopback test between applications on two nodes, thus testing all the supporting layers of the Digital Network Architecture (DNA).

The Loopback Application module has two components:

• The loop access module, which initiates the loopback test.
• The loop mirror module, which accepts connections from the remote loop access modules and mirrors any data sent to it back to the sender.

Figure 15-1 shows the hierarchical relationship of the entities that constitute the Loopback Application module.

Figure 15-1 Hierarchy of Loopback Application Module Entities

15.1 loopback application

loop

Starts a loop test between the loopback applications on the specified source and destination nodes. The node keyword specifies the node from which the loop messages are sent. If you omit this keyword, the test is performed from the node on which you issue the loop command. The name or address argument specifies the node whose loop mirror is used to reflect the messages back to the originator. Specify either the name or address (but not both).

address tower-set

Number of the destination for loopback messages, in the form of a protocol tower. Specify either this argument or the name argument.

count integer

Default: 1

Value: 0--4294967295

Number of loop messages to be sent to the loop mirror. The test is complete when this number of loop messages has been reflected back by the loop mirror.

format hex-string

Default: 55

Value: 00--FF

Content of the data field of a loop message. Enter a pair of hexadecimal digits. Each octet in the data field of a loop message has this value.

length integer

Default: 40

Value: 0--65534

Length, in octets, of the data field in each loop message.

maximum data

The maximum size, in octets, of the loop message data field that the loop mirror can reflect. If the loop mirror receives a loop message with a longer data field, an error occurs.

For Digital UNIX, to limit the number of loop mirrors, use the maximum instances characteristic of the session control application mir entity.

maximum mirrors integer

Default: 0

Value: 0--4294967295

Enter the maximum number of loop mirrors supported. If you enter the value 0, the node supports an unlimited number of mirrors.

For Digital UNIX, to limit the number of loop mirrors, use the maximum instances characteristic of the session control application mir entity.

name full-name

DNS name of the node to which loopback messages are sent. Specify either this argument or the address argument, but not both.

For loop:

bad data at mirror

There has been an error in the loopback protocol. The possible errors are:

• The local node sent a loop message with a data field that was too long.
• The first octet of the loop message was corrupted when it arrived at the mirror module.

Arguments:

count	Requested number of messages in the loopback test (that is, the value of the count argument).
message number	Number of the loop messages in which the error occurred.
start time	Time at which the loopback test began.

both name and address specified

Both the name and address arguments have been specified. You must specify one of these arguments, but not both.

connection failed

The Session Control connection to the loop mirror failed.

Arguments:

reason	Reason why the connection failed. This is the reason code provided by Session Control.
start time	Time the loopback test began.

data returned differs from data sent

The data field in a loop message reflected back by the loop mirror is not the same as the data field in the loop message that was sent.

Arguments:

count	Requested number of messages in the loopback test (that is, the value of the count argument).
format	Value for each octet of the data field of the loop message (that is, the value of the format argument).
length	Length of the data field of the loop message, as requested by the length argument.
message number	Number of the loop message in which the error occurred.
message returned	Contents of the reflected loop message.
start time	Time the loopback test began.

disconnected

The link to the loop mirror was disconnected before the loopback test was completed.

Arguments:

count	Requested number of messages in the loopback test (that is, the value of the count argument).
message number	Number of the loop message in which the error occurred.
reason	Reason why the link was disconnected. This is the reason code returned by Session Control.
start time	Time the loopback test began.

length too long

The requested length of the data field is greater than the maximum data field length that the loop mirror can handle.

Arguments:

length	Data field length requested, in octets.
maximum data	Maximum data field length supported by the loop mirror.
start time	Time at which the loopback test began.

neither name nor address specified

You have not specified the name or the address argument. You must specify one of these arguments, but not both.

This chapter describes all the commands you can use to manage the entities that constitute the Modem Connect module. The Modem Connect module implements one of the protocols in the Physical layer described by the Digital Network Architecture (DNA).

Note

For Digital UNIX, the Digital WAN Device Drivers product is provided as an installable subset within the product X.25 for Digital UNIX systems. You must install this subset before you can refer to the LAPB module entities in an NCL command.

Figure 16-1 shows the hierarchical relationship of the entities that constitute the Modem Connect module.

Figure 16-1 Hierarchy of Modem Connect Module Entities

16.1 modem connect

DNA version

Version number of the DNA Modem Connect architecture to which the implementation conforms. You cannot modify this characteristic.

16.2 modem connect data port

name

Simple name assigned to the data port when it is created.

client

Name supplied by the client when the port was opened. This defines which client owns the port.

line

Name of the modem connect line entity that the client supplied when the port was opened.

state

State of data port.

open	The port is assigned to a client.
open disabled	The port is assigned to a client, but the line entity that port refers to is disabled.

16.3 modem connect line

startloop

Causes a Physical layer to place the line in loopback mode.

stoploop

Opens a previously closed Physical layer loop to take it out of loopback mode.

communications mode mode

Communications method used on the link. This argument determines the value of the communications mode characteristic. The default value is taken from the device capability. If that is unknown, the default is synchronous.

communications port port-name

Name of the communications port to which the communications line is connected. This argument determines the value of the communications port characteristic and is required.

duplex duplex

Specifies whether the line is full-duplex or half-duplex. This argument determines the value of the duplex characteristic. The default value is taken from the device capability. If that is unknown, the default is set to full.

mode mode

Method of startloop used on line.

connector	Data is looped through a loopback connector attached to the communications device.
device	Data is looped in the communications device.
driver	Data is looped in the driver of the communications device.
external	Data is looped through a null modem or a modem in loopback mode.
local	Communications device has switched its local modem into loopback mode.
null	Line is not in loopback mode. This argument only applies to Digital UNIX.
remote	Communications device has switched the remote modem into loopback mode.

profile latin1string

Name of a local profile to be used with the line. This argument determines the value of the profile characteristic.

alternate speed

Default: 0

Alternate (low) speed, in bits per second, to operate the line. You can modify this characteristic only when the entity is disabled. This characteristic is supported only when the characteristic communications mode is asynchronous, the characteristic modem control is full, the characteristic modem options includes rateselect, the characteristic clock is internal, and when the alternate line speed is needed.

call accept timer

Default: 0

Minimum time, in milliseconds, between the assertion of data set ready and accepting a call by asserting request to send. This attribute is maintained only if the characteristic modem control is set to none.

carrier loss timer

Default: 15000

Maximum time, in milliseconds, that the carrier detect signal can be absent before the loss of carrier event is generated. This attribute is not supported if the characteristic modem control is set to none.

clock

Source of the transmit and receive clocks.

external	The modem provides the clock.
internal	The communications device provides the clock.
reflected	The DTE transmit clock is a reflection of the DCE transmit clock. This minimizes the clock to data skew that the DCE encounters when high line speeds are used.

The default value depends on the setting of the characteristic communications mode. If communications mode is asynchronous, the default value of this characteristic is internal. Otherwise, the default value is external.

The value of this attribute has no effect when the communications line is in loopback mode. In this case, the type of loopback determines the type of clock. This characteristic can only be modified when the entity is disabled.

communications mode

Default: Synchronous

Value: Asynchronous or synchronous

Communications method to be used on the line. The value of this characteristic is a copy of the communications mode argument specified when the entity is created. You cannot modify this characteristic.

communications port

Default: None

Name of the communications port. The value of this characteristic is a copy of the communications port argument specified when the entity is created.

connection type (Digital UNIX)

Default: Nonswitched

Value: Nonswitched or switched

Indicates whether the line is switched or nonswitched. The value of this characteristic is a copy of the connection type argument specified when the entity is created. You cannot modify this characteristic.

duplex

Default: Full

Value: Full or half

Indicates whether the line is full- or half-duplex. The value of this characteristic is a copy of the duplex argument specified when the entity is created.

encoding

Default: Normal

Value: Normal or nrzi

Encoding technique used on the line. This characteristic can only be modified when the entity is disabled.

initial hold timer (Digital UNIX)

Default: 10

Maximum time, in seconds, that the entity waits for an incoming call to be accepted.

maximum call setup timer (Digital UNIX)

Default: 60

Maximum time, in seconds, that the entity waits for the outgoing call to connect.

maximum disable transmit timer

Default: 500

Value: 0--60000

Maximum time, in milliseconds, that clear to send can remain asserted before the line is disconnected after request to send is de-asserted. This attribute is not supported if the characteristic modem control is set to none.

maximum dsr de-assertion timer

Default: 5000

Value: 0--60000

Maximum time, in milliseconds, the entity will wait for data set ready to be de-asserted after it has de-asserted data terminal ready. If this timer expires, the entity assumes it can assert data terminal ready once again. This attribute is not supported if the characteristic modem control is set to none.

maximum enable transmit timer

Default: 2000

Value: 1--5000

Maximum time, in milliseconds, between the assertion of the request to send signal and receiving the assertion of the clear to send signal. This attribute is not supported if the characteristic modem control is set to none.

minimum dtr de-assertion timer

Default: 1000

Value: 0--60000

Minimum time, in milliseconds, that the DTE will de-assert data terminal ready during a disconnection. This attribute is not supported if the characteristic modem control is set to none.

modem control

Default: Full

Value: Full or none

Indicates whether the interchange circuits are to be monitored and used. The value none means that only the data leads are monitored.

The value full must be used when the value of the characteristic duplex is half. This characteristic is supported only if the characteristic connection type is switched.

modem options

Default: No options

Value: Set of options

Set of values that determine the capabilities of the modem.

dialout	The modem can dial the remote modem. Supported only if the value of communications type is switched. This value is supported by Digital UNIX only.
direct	The modem is directly connected to the remote modem through a nonswitched line. Supported only if accompanied with dialout and used only when the modem protocol type supports direct dial. This value is supported by Digital UNIX only.
rate select	The modem is capable of data rate selection.

modem protocol format (Digital UNIX)

Default: See description

Value: See description

Format to use for V.25bis protocol messages. This characteristic applies only when the characteristic modem protocol type is v25bis or dmcl.

asynchronous	Use the asynchronous format.
hdlc	Use the HDLC format.
synchronous	Use the synchronous format.

---

Previous | Next | Contents | [Home] | [Comments] | [Ordering info] | [Help]

---

  NCL_PROFILE_013.HTML
  OSSG Documentation
   2-DEC-1996 12:48:05.35

Copyright © Digital Equipment Corporation 1996. All Rights Reserved.

Legal