CHGLINX25 (Change Line Description (X.25))

CHGLINX25 Command syntax diagram

 

Purpose

The Change Line Description (X.25) (CHGLINX25) command changes a line description for an X.25 line.

 

Required Parameters

LIND

Specifies the name of the line description being changed.

 

Optional Parameters

RSRCNAME

Specifies the resource name that describes the automatic call unit port.

Note:

Use the Work with Hardware Resources (WRKHDWRSC) command with *CMN specified for the TYPE parameter to help determine the resource name. The resource name is on the port. For example, the resource name may be CMN01 on a "Token-ring port". The value specified on the RSRCNAME parameter cannot be changed from *NWID to another value or from another value to *NWID.

*SAME: The value does not change.

*NWID: The resource name specified on the attached network interface description is used.

resource-name: Specify the resource name of the communications port. The resource name consists of the input/output adapter (IOA) resource name and the port number on the IOA. For example, if the resource name of the IOA is LIN01 and the port on the IOA is 2, the resource name would be LIN012.

LGLCHLE

Specifies, when using the Create Line Description (X.25) CRTLINX25 or CHGLINX25 command, a list of entries to be added, removed, or changed in the logical channel table. A channel entry consists of a channel identifier, a logical channel type, and a PVC controller.

Note:

Logical channel entries with attached permanent virtual circuit (PVC) controllers cannot be added, removed, or changed.

*SAME: The value does not change.

*PROMPT: By using the *PROMPT option, any entry can be added, removed, or altered. Specifying *PROMPT shows the current logical channel entries.

Element 1: Logical Channel Identifier

logical-channel-identifier: Specify a three-character hexadecimal number ranging from 001 through FFF for the logical channel identifier. The first digit (from left to right) is the logical channel group number; the second and third digits make up the logical channel number.

Element 2: Logical Channel Type

*PVC: The logical channel is a permanent virtual circuit.

*SVCIN: The logical channel is a switched virtual circuit for incoming calls.

*SVCOUT: The logical channel is a switched virtual circuit for calls going out.

*SVCBOTH: The logical channel is a switched virtual circuit for both calls coming in and calls going out.

NETADR

Specifies the local network address for this system.

*SAME: The value does not change.

network-address: Specify up to 15 decimal digits for the network address.

CNNINIT

Specifies the method used to establish the X.25 data link connection.

*SAME: The value does not change.

*LOCAL: The local system initiates the connection by issuing the set asynchronous balanced mode (SABM) communications command to establish the connection.

*REMOTE: The remote system initiates the connection by issuing the SABM communications command. The local system waits for the connection to be established.

*WAIT: The local system waits for the data circuit-terminating equipment (DCE) to send a disconnect (DISC) transmission control character or a disconnected mode (DM) response and then issues the SABM communications command.

*CALLER: The connection is initiated from either the local system or the remote system based on call direction.

ONLINE

Specifies whether this object is automatically varied on at initial program load (IPL).

*SAME: The value does not change.

*YES: The line is automatically varied on at IPL.

*NO: This line is not automatically varied on at IPL.

SWTNWILST

Specifies, for ISDN switched connections, a list of network interface descriptions to which this line can be attached. A network interface description is chosen from the list based on the value specified on the switched NWI selection parameter (SWTNWISLCT) at the time an incoming or outgoing call is processed.

*SAME: The value does not change.

*NONE: No network interface description is specified.

Element 1: Network Interface Description Name

nwi-description-name: Specify, for switched connections, the name of the network interface description to which this line attaches.

Element 2: Network Interface Channel Type

*B: The B channel is used.

Element 3: Network Interface Channel-Number

*CALC: The system selects one of the 30 channel numbers (based on availability) defined for the network interface description when an incoming or outgoing call is processed.

nwi-channel-number: Specify a channel number (1 or 30) to which the line description is restricted.

VRYWAIT

Specifies whether the line is varied on asynchronously or synchronously. For a synchronous vary on, this parameter specifies how long the system waits for the vary on to complete.

*SAME: The value does not change.

*NOWAIT: The system does not wait for the vary on to complete. The line is varied on asynchronously.

vary-on-wait: Specify the time (in seconds) to wait. Valid values range from 15 through 180. The system waits until the line is varied on, or until the specified time passes, before completing the Vary Configuration (VRYCFG) command.

 

Notes

1. When ONLINE(*YES) is used, specifying a wait time in the line description affects system IPL time. In such cases, system IPL time is influenced by the amount of time required to synchronously vary on the line or reach the wait-time value.
   
2. The time required to vary on a line is the time it takes to:

   • Put tasks in place to manage the line
     
   • Activate the communications I/O processor (IOP), including downloading the IOP model-unique Licensed Internal Code
     
   • Establish the communications tasks and processes

   Normal vary-on time ranges from 5 through 45 seconds, but can be longer, depending on the system, line protocol, and other factors.

LINESPEED

Specifies the line speed in bits per second (bps).

*SAME: The value does not change.

*CALC: The line speed is calculated by the system.

line-speed: Specify one of the following values (in bps) for the line speed:

     600    56000    512000   1088000   1664000
    1200    57600    576000   1152000   1728000
    2400    64000    640000   1216000   1792000
    4800   128000    704000   1280000   1856000
    7200   192000    768000   1344000   1920000
    9600   256000    832000   1408000   1984000
   14400   320000    896000   1472000   2048000
   19200   384000    960000   1536000
   48000   448000   1024000   1600000

PKTMODE

Specifies whether to access the ISDN virtual circuit service.

*SAME: The value does not change.

*NO: The ISDN network is used to provide transparent access to an X.25 packet switched network external to the ISDN (Case A).

*YES: The ISDN virtual circuit service is accessed (Case B).

INFTRFTYPE

Specifies the information transfer type. The information transfer type determines the layer 1 protocol.

*SAME: The value does not change.

*UNRESTRICTED: The data-channel traffic appears as digital information; no physical transformation is required and each B-channel operates at capacity (64k bps).

*V110: The transfer type is V-series Recommendation 110. Each B-channel operates at 56k bps.

*DOV Allows Data Over Voice (DOV) digital data to be transferred over an ISDN voice call. Also, this is referred to as Data Over Voice Bearer Service (DOVBS), Data Over Speech Bearer Service (DOSBS), TollSaver, or TollMizer. This option should only be used if an ISDN voice call is less expensive than an ISDN data call or if a bearer service for data is not available. The remote location must also support this feature. Data is transferred at 56Kbps in each direction.

*SYNCMODEM: Allows data from the integrated synchronous modem to be transferred over an ISDN voice call. This option should be used to connect to a remote location that is using a synchronous modem on an analog telephone line. Data is transferred at modem speeds up to 33.6Kbps from the remote analog device to this digital connection and up to 56Kbps from this digital connection to the remote analog device.

Note:

INFTRFTYPE(*SYNCMODEM) can be specified only if the description was created with CNN(*NONSWTCALL) or CNN(*NONSWTANS).

EXNNETADR

Specifies whether network addressing is extended to permit the use of 17 characters in an address name.

*SAME: The value does not change.

*NO: Network addresses can be up to 15 characters.

*YES: Network addresses can be up to 17 characters.

MAXFRAME

Specifies the maximum frame size that can be transmitted and received on this line description.

*SAME: The value does not change.

max-frame: Specify one of the following values: 1024, 2048, or 4096.

DFTPKTSIZE

Specifies the default packet size used by the X.25 network.

Element 1: Transmit Packet Size

*SAME: The value does not change.

transmit-packet-size: Specify a default packet size for transmission to all controllers that will attach to this line. The controllers can override this default with the DFTPKTSIZE parameter on the controller commands. The valid values for the packet size are 64, 128, 256, 512, 1024, 2048, and 4096.

Element 2: Receive Packet Size

*SAME: The value does not change.

*TRANSMIT: The value specified as the default packet size for transmission is used as the default for reception.

receive-packet-size: Specify a default packet size for reception from all controllers that will attach to this line. The controllers can override this default with the DFTPKTSIZE parameter on the controller commands. The valid values for the packet size are 64, 128, 256, 512, 1024, 2048, and 4096.

MAXPKTSIZE

Specifies the maximum packet size for transmission and reception on an X.25 network. The value specified must not be less than the default packet size specified.

Element 1: Maximum Transmit Packet Size

*SAME: The value does not change.

*DFTPKTSIZE: The maximum packet size for transmission is the same as that specified as the default packet size for transmission in the DFTPKTSIZE parameter in this command.

transmit-packet-size: Specify a packet size. The valid values for the packet size are 64, 128, 256, 512, 1024, 2048, and 4096.

Element 2: Maximum Receive Packet Size

*SAME: The value does not change.

*DFTPKTSIZE: The maximum packet size for reception is the same as that specified as the default package size for reception in the DFTPKTSIZE parameter in this command.

*TRANSMIT: The value specified as the default packet size for transmission is used as the default for reception.

receive-packet-size: Specify a default packet size for reception from all controllers that will attach to this line. The controllers can override this default with the DFTPKTSIZE parameter on the controller commands.

MODULUS

Specifies the packet numbering used. The valid numbers are listed below.

*SAME: The value does not change.

8: Character density is 18 characters per inch. This value is valid only on double-byte character set (DBCS) printers.

128: Modulus 128 packet numbering is used.

DFTWDWSIZE

Specifies the default window size used by the X.25 network.

Element 1: Transmit Window Size

*SAME: The value does not change.

transmit-window-size: Specify the appropriate default window size. Valid values range from 1 through 7 for networks that use modulus 8 packet numbering. Valid values range from 1 through 15 for networks that use modulus 128 packet numbering.

Element 2: Receive Window Size

*SAME: The value does not change.

*TRANSMIT: The value specified as the default window size for transmission is used as the default for reception.

receive-window-size: Specify the appropriate default window size. Valid values range from 1 through 7 for networks that use modulus 8 packet numbering. Valid values range from 1 through 15 for networks that use modulus 128 packet numbering.

NETCTL

Specifies the name of an existing network controller.

SWTCTLLST

Specifies the names of up to 64 switched asynchronous X.25 controllers or specify *ALL for unlimited number of switched asynchronous X.25 controllers that can establish a connection with an X.25 switched virtual circuit (SVC). The controller descriptions must already exist, and must have been created by using the Create Controller Description (Async) (CRTCTLASC) command. Asynchronous X.25 controllers that are specified as dial-in can be connected to SVCIN or SVCBOTH logical channels. Attaching controllers that specify CNNNBR(*ANY) or ANSNBR(*ANY) may result in a reordering of this list.

Note:

If *ALL is specified and no switched asynchronous X.25 controllers exist on the system that specifies this line description on the switched line list (SWTLINLST) parameter then all incoming calls will be rejected.

*SAME: The value does not change.

*NONE: No switched controllers are specified.

*ALL: All X.25 switched controllers that are created using the Create Controller Description (Async) (CRTCTLASC) command and list this line description on the Switched Line List (SWTLINLST) parameter can be used to establish a connection with an X.25 switched virtual circuit (SVC).

switched-controller-name: Specify the switched controller name.

NETUSRID

Specifies, for switched lines, whether network user identification (NUI) information should be included in the facility field of call request packets sent on this line. The NUI facility identifies calling data terminal equipment (DTE) to the network.

*SAME: The value does not change.

*NONE: No NUI information is sent over this line.

network-user-identification: Specify the hexadecimal NUI that will sent. The system will insert the NUI facility code (X'C6') and the NUI length in the facility field of a call request packet.

IDLTMR

Specifies the maximum amount of time (in 0.1 second intervals) that the system waits for acknowledgment from the network for each frame sent before re-transmission.

Note:

The IDLTMR value should be greater than or equal to the value of the following equation:

(2 * P + (MAXPKTSIZE*8)/LINESPEED + D) * 10

where "P" is the propagation delay (in seconds) of the medium that connects the user to the network, MAXPKTSIZE is the maximum transmit packet size, and "D" is the DCE (Data Circuit-terminating Equipment) processing overhead (in seconds). Contact the network provider for information about variables P and D.

*SAME: The value does not change.

idle-timer: Specify a value ranging from 4 through 600. Each unit represents 0.1 seconds, which provides a timeout value ranging from 0.4 through 60 seconds.

FRAMERTY

Specifies the maximum number of retries attempted for various error conditions on the interface, such as link level time-outs, logical link level re-transmissions, and others.

*SAME: The value does not change.

frame-retry: Specify a ranging value from 0 through 64.

ADRINSERT

Specifies whether the system inserts the local network address in CALL REQUEST or CALL ACCEPTED packets.

*SAME: The value does not change.

*YES: The local network address is inserted in packets.

*NO: The local network address is not inserted in packets.

X25DCE

Specifies whether the system communicates by using the X.25 (DCE) support. It allows a system to communicate with another system without going through an X.25 network.

*SAME: The value does not change.

*YES: The iSeries 400 does communicate by using the X.25 (DCE) support.

*NO: The iSeries 400 does not communicate by using the X.25 (DCE) support.

*NEG: The iSeries 400 negotiates with another system about whether to communicate by using the X.25 (DCE) support. This value can only be specified for switched lines.

THRESHOLD

Specifies the temporary error threshold level being monitored by the system. A permanent error is reported only if the errors occurred consecutively and exceeded the retry limit.

Note:

Specifying the THRESHOLD parameter affects all threshold errors. They cannot be specified individually.

*SAME: The value does not change.

*OFF: No monitoring of errors occurs.

*MIN: The error threshold is set at a minimum monitoring level.

*MED: Error thresholding is set to a medium monitoring level.

*MAX: The error threshold is set at a maximum monitoring level.

CNNNBR

Specifies, for switched lines, the telephone number used to establish a switched connection on this line description. The value specified on this parameter is sent to the autocall unit if automatic calling is used to establish a switched connection, or it is sent to the V.25 bis modem if V.25 bis automatic dialing is used to establish the connection. When manual dialing is used to establish a switched connection on the line, this number is displayed to the system operator. For X.25, this number is the remote data terminal equipment (DTE) address for the switched virtual circuit (SVC) provided by the X.25 network.

*SAME: The value does not change.

connection-number: Specify the telephone number dialed to establish a switched connection on this line description.

CALLNBR

Specifies the local telephone number of the line used for the V.25 bis call request with identification (CRI) dial command. This parameter is used when the CRI function is needed for V.25 bis. When V.25 bis CRI dialing is used, the system takes the called (connection) number from the CNNNBR parameter of the controller description, adds a separator character (;), and concatenates the calling number at the end. Specify the calling number only if the modem and the network both support the CRI dial command.

*SAME: The value does not change.

*NONE: Specifies that the CRN (Call Request Normal) dial command is used by the V.25 bis line.

calling-number: Specify up to 32 characters that represent the local telephone number for V.25 bis CRI (Call Request with Identification) auto-dialing.

MODEM

Specifies the type of modem supported on the communications line. Refer to the modem information to select the appropriate value.

*SAME: The value does not change.

*NORMAL: No attempt is made to run diagnostic tests on the modem.

*V54: Certain types of diagnostic tests (as defined by the CCITT recommendations) are run to the modem. The iSeries 400 supports CCITT V.54 loop 3 (local loop back) and loop 2 (a remote loop back).

*IBMWRAP: An IBM modem with wrap test capabilities is used on the communications line.

MODEMRATE

Specifies the speed at which the line operates if the modem has the data rate select feature.

Note:

The user is responsible for ensuring that the line speed corresponds to the actual modem rate.

*SAME: The value does not change.

*FULL: The line operates at the full rate of the modem.

*HALF: The line operates at half the full rate, or at the alternate rate, of the modem.

SWTCNN

Specifies whether the switched or switched network backup (SNBU) line is used for incoming calls, outgoing calls, or both incoming and outgoing calls.

*SAME: The value does not change.

*BOTH: The line is used for both incoming and outgoing calls.

*ANS: The line is used for incoming calls only.

*DIAL: The line is used for outgoing calls only.

CNNLSTOUT

Specifies, for ISDN switched connections, the name of a connection list object that contains the ISDN assigned numbers for a dial-out operation to the ISDN.

*SAME: The value does not change.

*NONE: A user specified connection list for dial-out operations is not used. The connection list is automatically configured if OSI Communications Subsystems/400 is installed.

connection-list-name: Specify the connection list object name.

CNNLSTOUTE

Specifies, for ISDN switched connections, the entry name from the connection list used to make a call to the ISDN. The connection list must be specified on the CNNLSTOUT parameter.

*SAME: The value does not change.

connection-list-entry-name: Specify the entry name from the connection list.

CNNLSTIN

Specifies for ISDN switched connections the name of the connection list that is used to retrieve call information (or connection) for identifying authorized incoming calls.

*SAME: The value does not change.

*NETATR: The connection list used by this line description is taken from the list of system default network attributes that were identified at IPL (Initial Program Load). The Display Network Attributes (DSPNETA) command can be used to see the name of the connection list.

connection-list-name: Specify the name of the connection list used for this line description.

AUTOANS

Specifies, for switched or switched network backup (SNBU) lines, whether the system automatically answers a call from a remote system to establish the connection or whether the user must manually answer the call and place the modem in data mode.

*SAME: The value does not change.

*YES: The system automatically answers incoming calls.

*NO: The system operator must manually answer incoming calls.

Note:

*YES is valid only if the modem has the automatic answer feature.

AUTODIAL

Specifies, for switched or switched network backup (SNBU) lines, whether the system automatically calls a remote system to establish a connection or whether the system operator must manually place the call.

*SAME: The value does not change.

*NO: The iSeries 400 does not automatically call a remote system.

*YES: The iSeries 400 automatically calls a remote system.

Note:

*YES is only valid if the system is using an autocall unit or if the modem used is capable of calling though a command interface.

DIALCMD

Specifies the type of dial command used to establish a switched connection with a remote system.

*SAME: The value does not change.

*NONE: No dial command type is specified. An automatic call unit establishes the connection.

*V25BIS: V.25 bis is a recommendation which allows the use of one physical interface for call establishment and data transmission. It is sometimes referred to as a serial automatic call interface because the digits are presented serially on the link from the system (DTE) to the modem (DCE).

MDMINZCMD

Specifies the modem initialization command string sent to set the modem.

Note:

Valid only when INTERFACE(*INTMODEM) or INFTRFTYPE(*SYNCMODEM) was specified on the create.

*SAME: The value does not change.

*NONE: No command string is sent to the modem.

command-string: Specifies up to 60 characters that represent the command string sent to the modem. Valid characters are upper case A thru Z, lower case a thru z, numbers 0 thru 9, and special characters:

Table 1. Special characters

Character	Description
.	Period
<	Less than sign
(	Left parenthesis
+	Plus sign
&	Ampersand
*	Asterisk
)	Right parenthesis
;	Semicolon
-	Minus sign
/	Slash
,	Comma
_	Underline
>	Greater than sign
?	Question mark
:	Colon
=	Equal sign
	Spaces
#	Number sign
"	Double quote
!	Exclamation mark
@	At sign
^	Circumflex
%	Percent
[	Left square bracket
]	Right square bracket
\	Back slash
$	Dollar sign

Note: The first two characters of the modem initialization command string must begin with 'AT'. These first two characters must be in uppercase.

CALLIMMED

Specifies, for switched (CNN(*SWTPP)) lines, whether a call (using the number specified by the CNNNBR parameter) should be made immediately after varying on the line description.

*SAME: The value does not change.

*NO: The call is not made immediately after varying on. It must be initiated by an application program.

*YES: The call is made immediately after varying on.

AUTOCALL

Specifies, for switched lines, whether the line has an associated autocall unit which performs automatic calling to the remote system.

*SAME: The value does not change.

*NO: The switched line does not have an autocall unit.

*YES: The switched line has an autocall unit.

ACRSRCNAME

Specifies the resource name that describes the automatic call unit port. The resource name consists of the input/output adapter (IOA) resource name and the port number on the IOA. For example, if the resource name of the IOA is LIN02 and the port is 1, the resource name is LIN021.

*SAME: The value does not change.

autocall-resource-name: Specify the resource name that describes the automatic call unit port.

PREDIALDLY

Specifies how long to wait (in 0.5 second intervals) before dialing.

Note:

This parameter is valid only for switched lines (CNN(*SWTPP)).

*SAME: The length of time does not change.

predial-delay: Specify a value ranging from 1 through 254 in 0.5 second intervals, or specify 0 to indicate no delay.

REDIALDLY

Specifies the length of time (in 0.5-second intervals) to wait before re-dialing when the call attempt is unsuccessful. This parameter can be specified only if CNN(*SWTPP) is also specified.

*SAME: The value does not change.

redial-delay: Specify a number ranging from 1 through 254 (measured in 0.5 second intervals), or specify 0 to indicate no delay.

DIALRTY

Specifies the number of re-dial attempts made by the system before considering the dialing unsuccessful.

Note:

Dial retries can only be specified for switched lines (CNN(*SWTPP)).

*SAME: The value does not change.

dial-retry: Specify a value ranging from 0 to 254 for the number of dial attempts.

SWTDSC

Specifies whether the switched connection on this line is disconnected when the last switched virtual circuit (SVC) is cleared.

*SAME: The value does not change.

*YES: The switched connection is disconnected when the last device is varied off.

*NO: The switched connection is not disconnected when the last switched virtual circuit is cleared.

SWTDSCTMR

Specifies the settings for the timers that run when switched X.25 lines are disconnected from the network or remote system.

Element 1: Settings for the Minimum Connect Timer

*SAME: The value does not change.

minimum-connect-timer: Specify the minimum length of time (in seconds) the system keeps the connection active. This timer is started when the connection is established. Valid values for the minimum length timer range from 0 to 65535 seconds.

Element 2: Settings for the Disconnect Delay Timer

disconnect-delay-timer: Specify the length of time (ranging from 0 through 65535 seconds) the system waits before disconnecting the switched line connection. The system disconnects the switched connection only when the following conditions occur:

• The line is idle
  
• The minimum connect timer has expired
  
• The disconnect delay timer has expired

DSRDRPTMR

Specifies the amount of time the system waits for the modem to exit the Data Set Ready (DSR) state before signaling an error.

*SAME: The value does not change.

DSR-drop-timer: Specify a value ranging from 3 through 60 seconds.

AUTOANSTYP

Specifies the method the system uses to answer incoming calls.

*SAME: The value does not change.

*DTR: The system enters the Data Terminal Ready state, signals the modem to answer calls, and waits for the modem to enter the Data Set Ready (DSR) state.

*CDSTL: The system enters the Connect Data Set to Line (CDSTL) state after monitoring the Ring Indicator to signal the modem to answer the call.

CTSTMR

Specifies the amount of time the system waits for the modem to enter or exit the Clear to Send (CTS) state before signaling an error.

*SAME: The value does not change.

CTS-timer: Specify a value ranging from 10 through 60 seconds.

RMTANSTMR

Specifies the amount of time the system waits for the modem to enter the Data Set Ready (DSR) state after dialing before signaling an error.

*SAME: The value does not change.

answer-timer: Specify a value ranging from 30 through 120 seconds.

CLOCK

Specifies how the clocking function for the line is provided.

*SAME: The value does not change.

*MODEM: The modem supplies the clocking function.

*LOOP: The receiving clock provided by the modem data circuit-terminating equipment (DCE) is looped back to the modem (DCE) on the system data terminal equipment (DTE) transmitting clock. This option can be used to improve high speed data transmission when the modem (DCE) supports such an option.

*INVERT: The transmit clock provided by the modem data circuit-terminating equipment (DCE) is inverted before use. This option can be used when having problems with high speed data tranmission and the modem (DCE) does not support looped clocking. The valid interfaces for *INVERT are *X21, *X21BISV35, and *RS449V36.

LINKSPEED

Specifies the link speed in bits per second (bps). This parameter is valid only if APPN* support is used on the system.

*SAME: The value does not change.

*INTERFACE: The following link speeds, based on the physical interface type, are used: 9600 bps for RS-232/V.24 and X.21bis/V.24, 48000 bps for V.35 and X.21bis/V.35, and 64000 bps for X.21 and RS-449/V.36.

*MIN: The minimum link speed is used.

*MAX: The maximum link speed is used.

link-speed: Specify the link speed. Valid values are: 1200, 2400, 4800, 7200, 9600, 14400, 19200, 48000, 56000, 64000, 128000, 192000, 256000, 320000, 384000, 448000, 499000, 576000, 614000, 691000, 768000, 845000, 922000, 998000, 1075000, 1152000, 1229000, 1382000, 1536000, 1690000, 1843000, 1997000, 4M, 10M, and 16M.

SWTNWISLCT

Specifies the method used to select network interfaces from the switched network interface list.

*SAME: The value does not change.

*FIRST: Selection begins with the first network interface specified in the switched network interface list.

*CALC: The system calculates which network interface is selected.

COSTCNN

Specifies the relative cost of being connected on the line. This parameter is required only if APPN* support is used on the system.

*SAME: The value does not change.

cost-per-connect-time: Specify a value ranging from 0 through 255.

COSTBYTE

Specifies the relative cost per byte for sending and receiving data on the line. This parameter is required only if APPN* support is used on the system.

*SAME: The value does not change.

cost-per-byte: Specify a value ranging from 0 through 255.

SECURITY

Specifies the security level of the physical line. This parameter is used only if APPN is used on the system.

*SAME: The value does not change.

*NONSECURE: Normal priority is used.

*PKTSWTNET: A packet switched network is used. Data does not always follow the same path through the network.

*UNDGRDCBL: An underground cable is used.

*SECURECND: A secure, unguarded conduit (for example, a pressurized pipe) is used.

*GUARDCND: A guarded conduit, which is protected against physical tapping, is used.

*ENCRYPTED: Data flowing on the line is encrypted.

*MAX: A guarded conduit, protected against physical and radiation tapping, is used.

PRPDLY

Specifies the level of propagation delay on the line. This parameter is valid only if APPN* support is used on the system. The order of the values from shortest to longest delay is *MIN, *LAN, *TELEPHONE, *PKTSWTNET, and *SATELLITE.

*SAME: The value does not change.

*MIN: The minimum propagation delay is used.

*LAN: The local area network propagation delay is used.

*TELEPHONE: The telephone propagation delay is used.

*PKTSWTNET: The packet switched network propagation delay is used.

*SATELLITE: The satellite propagation delay is used.

*MAX: The maximum propagation delay is used.

USRDFN1

Specifies the first of the three user-defined fields. This field is used to describe unique characteristics of the line that is controlled. This parameter is valid only if APPN* support is used on the system.

*SAME: The value does not change.

user-defined-1: Specify a value ranging from 0 through 255.

USRDFN2

Specifies the second of the three user-defined fields. This field is used to describe unique characteristics of the line that is controlled. This parameter is valid only if APPN* support is used on the system.

*SAME: The value does not change.

user-defined-2: Specify a value ranging from 0 through 255.

USRDFN3

Specifies the third of the three user-defined fields. This field is used to describe unique characteristics of the line that is controlled. This parameter is valid only if APPN is used on the system.

*SAME: The value does not change.

user-defined-3: Specify a value ranging from 0 through 255.

CMNRCYLMT

Specifies the number of recovery attempts made by the system before an inquiry message is sent to the system operator. Also specifies the time (in minutes) that must elapse before the system sends an inquiry message to the system operator indicating that the recovery attempt count limit is reached.

*SAME: The value does not change.

*SYSVAL: The recovery limits specified in the QCMNRCYLMT system value are used.

Element 1: Maximum Recovery Limit

count-limit: Specify the number of recovery attempts to be made. Valid values range from 0 through 99.

Element 2: Recovery Time Interval

time-interval: Specify the time interval (in minutes) at which the specified number of second-level recoveries are attempted. Valid values range from 0 through 120. If the value specified for count-limit is not 0, the value 0 specifies infinite recovery.

MSGQ

Specifies the qualified name of the message queue to which messages are sent. More information about using this parameter is in the Communications Management book.

Single Values

*SAME: The value does not change.

*SYSVAL: Messages are sent to the message queue defined in the system value QCFGMSGQ.

*SYSOPR: Messages are sent to the system operator message queue (QSYS/QSYSOPR).

library-name/message-queue-name: Specify the library-qualified name of the message queue to which operational messages are sent.

TEXT

Specifies the text that briefly describes the program and its function. More information is in Commonly used parameters.

*SAME: The value does not change.

*BLANK: Text is not specified.

'description': Specify no more than 50 characters of text, enclosed in apostrophes.

Example for CHGLINX25

CHGLINX25   LIND(X251)  LGLCHLE(*PROMPT)
  MAXPKTSIZE(512)

This command shows an interactive display listing all current logical channel entries and allows changes to be made to these entries. Maximum packet size will be changed to 512 bytes.

Error messages for CHGLINX25

*ESCAPE Messages

CPF261E

Line description &1 not changed.