Use the LOOP CIRCUIT, LOOP EXECUTOR, LOOP LINE, and LOOP NODE
commands to test specified components in the network.  Each
command causes test blocks of data to be transmitted over the
specified components.  The parameters can be entered in any order
and are optional, except in the case of Ethernet circuit loopback
tests which require a parameter to define the loopback destination.

LOOP    CIRCUIT circuit-id    (parameters ...)
        EXECUTOR
        LINE    line-id
        NODE    node-id

Additional information available:

CIRCUITEXECUTORLINENODE

Use the LOOP CIRCUIT command to test a specified circuit in the
network.  This command does not apply to X25 circuits.  The
parameters are optional and can be entered in any order.

LOOP   CIRCUIT circuit-id   ASSISTANT PHYSICAL ADDRESS E-address
                            ASSISTANT NODE node-id
                            COUNT number
                            HELP help-type
                            LENGTH number
                            NODE node-id
                            PHYSICAL ADDRESS E-address
                            WITH
                              MIXED
                              ONES
                              ZEROES

All underscores found in parameters must be replaced with spaces
when parameters are used in NCP commands.

Additional information available:

ASSISTANT

COUNT numberHELP help-typeLENGTH numberNODE node-id
PHYSICAL ADDRESS E-addressWITH data-typeExamples

Additional information available:

PHYSICAL ADDRESS E-addressNODE node-id

applies only to Ethernet circuits.  Identifies the Ethernet
physical address of the node that will perform the role of
loopback assistant for Ethernet third-party loop testing.
This parameter must be specified if HELP is included in this
command. The address cannot be a multicast address.
This parameter can be used instead of the ASSISTANT NODE parameter.

applies only to Ethernet circuits.  Identifies the name of the
node or the address of the node that will perform the role of
loopback assistant for Ethernet third-party loop testing.  This
parameter can be used instead of the ASSISTANT PHYSICAL ADDRESS
parameter.

specifies the number of blocks to be sent during loopback
testing over the circuit.  The count must be a decimal
integer in the range of 1 through 65535. If the parameter is
omitted, only one block is looped.

applies only to Ethernet circuits.  Indicates the amount of
assistance to be provided during Ethernet loopback testing by
the assistant node, whose address is specified in the ASSISTANT
PHYSICAL ADDRESS or node-id as specified in the ASSISTANT NODE
parameter.  There are three possible values of help-type:

  TRANSMIT   The assistant node relays the request to the
             destination node, which replies directly to the
             executor node.

  RECEIVE    The executor node sends the request directly to the
             destination node, which relays the reply to the
             assistant node for transmission to the executor node.

  FULL       The assistant node relays the request and the reply
             between the executor node and the destination node.

If HELP is specified, ASSISTANT PHYSICAL ADDRESS or ASSISTANT
NODE must also be specified.

specifies the length (in bytes) of the blocks to be sent
during loopback testing.  The length must be a decimal
integer in the range of 1 through 65535.  Note that the
LENGTH parameter must be less than 50 for the DMC-11 circuit
operating in either controller loopback mode or cable
loopback mode (a DMC-11 with an attached loopback cable).
If the parameter is omitted, a block length of 40 bytes is used.

applies only to Ethernet circuits. Identifies the destination node
to be used for loopback testing of the specified Ethernet circuit.
Can be used instead of the PHYSICAL ADDRESS parameter.

applies only to Ethernet circuits.  Identifies the Ethernet physical
address of the destination node to be used for loopback testing of
the specified Ethernet circuit.

specifies the type of binary information to be sent during
testing. Three types of data can be sent:

                MIXED
                ONES
                ZEROS

If omitted, a combination of ones and zeros (MIXED) is sent.

     NCP>LOOP CIRCUIT DMC-0 COUNT 5 LENGTH 20

         This command initiates a circuit-level loopback test over circuit
         DMC-0.  The software loops five messages, 20 bytes in length with
         mixed binary information.

     NCP>LOOP CIRCUIT UNA-0 NODE 224

         This command initiate an Ethernet circuit-level loopback test
         with a node whose address is 224.  In this example, the NODE
         parameter with a node-id of 224 was used in place of the
         PHYSICAL ADDRESS parameter.

Use the LOOP EXECUTOR command to test the executor node in the
network.  The parameters are optional and can be entered in any
order.  You can supply explicit access control information for
the LOOP EXECUTOR command.  This command does not apply to VAX
PSI.

LOOP    EXECUTOR      ACCOUNT account
                      COUNT number
                      LENGTH number
                      PASSWORD password
                      USER user-id
                      WITH
                        MIXED
                        ONES
                        ZEROS

Additional information available:

ACCOUNTCOUNTLENGTHPASSWORDUSERWITH

Example

identifies the user's account for access control verification
for the executor node.

specifies the number of blocks to be sent during loopback
testing over the executor node. The count must be a decimal
integer in the range of 1 through 65535. If the parameter is
omitted, only one block is looped.

specifies the length (in bytes) of the blocks to be sent
during loopback testing. The length must be a decimal
integer in the range of 1 through 65535. If the parameter is
omitted, a block length of 40 bytes is used.

identifies the user's password for access control verification
for the executor node.

specifies the user's identification for access control
verification for the executor node.

specifies the type of binary information to be sent during
testing. Three types of data can be sent:

                MIXED
                ONES
                ZEROS

If omitted, a combination of ones and zeros (MIXED) is sent.

     NCP>LOOP EXECUTOR

         This command initiates a loopback test on the executor node.

Use the LOOP LINE command to initiate loopback testing of X25 lines
only.  The parameters are optional and can be entered in any order.
Before beginning loopback testing of an X25 line, use the SET LINE
command to set the STATE SERVICE and CONTROLLER LOOPBACK parameters
for internal loopback testing or the STATE SERVICE and CONTROLLER
NORMAL for all other loopback testing.

LOOP    LINE line-id        COUNT number
                            LENGTH number
                            WITH
                              MIXED
                              ONES
                              ZEROS

Additional information available:

COUNTLENGTHWITH

Examples

specifies the number of blocks to be sent during loopback
testing over the line. The count must be a decimal
integer in the range of 1 through 65535. If the parameter is
omitted, only one block is looped.

specifies the length (in bytes) of the blocks to be sent
during loopback testing. The length must be a decimal
integer in the range of 1 through 65535. If the parameter is
omitted, a block length of 40 bytes is used.

specifies the type of binary information to be sent during
testing. Three types of data can be sent:

                MIXED
                ONES
                ZEROS

If omitted, a combination of ones and zeros (MIXED) is sent.

     NCP>LOOP LINE DUP-0

         This command initiates a line-level loopback test over
         X25 line DUP-0.  The software loops one message, 40 bytes
         in length, with mixed binary information.

     NCP>LOOP LINE DUP-1 COUNT 10 WITH ONES

         This command initiates a line-level loopback test over
         X25 line DUP-1.  The software loops 10 messages, 40 bytes
         in length, with all binary ones information.

Use the LOOP NODE command to test a specified node (other than the
executor node) in the network.  The parameters are optional and can
be entered in any order.  You can supply explicit access control
information for the LOOP NODE command.

To test the executor, use the LOOP EXECUTOR command.

LOOP    NODE  node-id      ACCOUNT account
                           COUNT number
                           LENGTH number
                           PASSWORD password
                           USER user-id
                           WITH
                             MIXED
                             ONES
                             ZEROS

Additional information available:

ACCOUNTCOUNTLENGTHPASSWORDUSERWITH

Example

identifies the user's account for access control verification
for the designated node.

specifies the number of blocks to be sent during loopback
testing over the node. The count must be a decimal integer in
the range of 1 through 65535. If the parameter is omitted,
only one block is looped.

specifies the length (in bytes) of the blocks to be sent
during loopback testing. The length must be a decimal
integer in the range of 1 through 65535. If the parameter is
omitted, a block length of 40 bytes is used.

identifies the user's password for access control verification
for the designated node.

specifies the user's identification for access control
verification for the designated node.

specifies the type of binary information to be sent during
testing. Three types of data can be sent:

                MIXED
                ONES
                ZEROS

If omitted, a combination of ones and zeros (MIXED) is sent.

     NCP>SET NODE TESTER CIRCUIT DMC-0
     NCP>LOOP NODE TESTER
        .
        .
        .
     NCP>CLEAR NODE TESTER CIRCUIT

         The first command creates a loop node name (TESTER) for
         the associated circuit, the second command initiates a
         node-level loopback test with the loop node name, and the
         third command removes the loop node name from the volatile
         database when the loopback is completed.