HP OpenVMS Systems Documentation

Refer to Section 9.2.1 in DECnet-Plus FTAM and Virtual Terminal Use and Management for a complete description of Address format entries. Entries of the Address format take the following form:

alias   :application:ap-title:ae-qualifier:psel.ssel.tsel.
                                           nsap,transport_options;
                                           nsap,transport_options; ...
                                           nsap,transport_options:

Use the information you completed in the Address Format Worksheet to add the Address format entries. For example, an Address format entry for VT could look like the following:

remote1 :VT:::psap.ssap.tsap.%x4145418715004108002B23569821, \
                             provider=osi,template=default:

Note that you can enter more than one NSAP per alias.

12.5.2 Adding Distinguished Name Format Entries

Refer to Section 9.2.2 in DECnet-Plus FTAM and Virtual Terminal Use and Management for a complete description of Distinguished Name entries. Entries of the Distinguished Name format take the following form:

alias   :application:template_list:x500_distinguished_name:

Use the information you completed in the configuration checklist to add the Distinguished Name format entries. For example, a Distinguished Name format entry for FTAM could look like the following:

remote2 :FTAM:template=default:/c=us/o=org/ou=org_unit/cn=remote2/cn=ftam:

Refer to Section 9.2.3 in DECnet-Plus FTAM and Virtual Terminal Use and Management for a complete description of Pattern format entries. Entries of the Pattern format take the following form:

*   :application:template_list:incomplete_distinguished_name:

You need only one Pattern format entry in isoapplications for each application (FTAM or VT). Use the information you completed in the configuration checklist to add the Pattern format entries.

For example, the aliases passed to the FTAM and VT commands could correspond to the value of the common name attribute of the application process entries in the X.500 directory. In this case, you might use the following two isoapplications entries:

*   :VT:template=default:/c=us/o=org/ou=org_unit/cn=*/cn=vt:
*   :FTAM:template=default:/c=us/o=org/ou=org_unit/cn=*/cn=ftam:

If you have DEC X.500 Directory Service available to you, you have the option of storing the addresses of the local FTAM and VT responders in the X.500 Directory database. Use the information you completed in the configuration checklist to register your local responders.

For example, you could use the following DEC X.500 Administration Facility (DXIM) command to register your local FTAM responder on node srchr, assuming that srchr already exists in the database as an application process.

dxim> create /c=us/o=local_org/ou=local_org_unit/cn=srchr/cn=ftam - [Return]
_dxim> attributes objectclass=applicationentity, - [Return]
_dxim> presentationaddress="RMS"/"FTAM"/"OSIF"/NS+410004AA000400001321 [Return]

Part V includes the following two appendixes:

• Appendix A --- Configuring Asynchronous Connections
• Appendix B --- Configuring NSP and the OSI Transport Service

This appendix describes how to configure asynchronous connections, which give you the option of connecting your OpenVMS system to another system by means of a low-cost, low-speed asynchronous line. Asynchronous connections are implemented in software and can be run over any directly connected terminal line that the OpenVMS system supports.

The asynchronous protocol provides for a full-duplex connection and can be used for remote asynchronous communications over a telephone line using a modem. Asynchronous connections are not supported for maintenance operations or for controller loopback testing.

A.1 Asynchronous DECnet Connections

Normally, the OpenVMS system controls lines connected to terminal ports, as in interactive logins. You can, however, switch the line so the DECnet-Plus software can use the line for an asynchronous connection to another system. You can establish two types of asynchronous DECnet connections:

• A static asynchronous connection, which creates a permanent DECnet link to a single remote node. Two nodes are connected by either a dialup line or by a physical line attached to a terminal port at each end. Before the DECnet connection is made, the terminal lines must be converted to static asynchronous DDCMP lines. (See Section A.1.1.)
• A dynamic asynchronous connection, which provides a temporary DECnet link. A dynamic asynchronous line is normally switched on for network use only for the duration of a dialup connection between two nodes. When the telephone is hung up, the line reverts to being a terminal line. You can establish dynamic connections to different remote nodes at different times. When using a dynamic connection, you can have the terminal line switched automatically to a DECnet line, or you can switch it to a DECnet line manually. (See Section A.1.2.)

The asynchronous software is optional. You can load and configure it by using the net$configure.com, net$startup.com, and wandd$startup.com procedures.

The asynchronous software consists of three pieces:

• asydriver
• asyswitch
• asydynswitch

To switch a terminal line to a DECnet line or a DECnet line back to a terminal line, you use DCL set commands such as the following:

• To switch a DECnet line back to ttdriver:

  $ set terminal/nonetwork terminal-port

• To switch a terminal line to a static asynchronous line (asydriver):

  $ set terminal/network terminal-port

• To switch a terminal line to a dynamic asynchronous line (asydriver):

  $ set terminal/network/switch=decnet

• To switch a terminal line to a dynamic manual asynchronous line (asydriver):

  $ set terminal/network/switch=decnet/manual

Switching the line is only one step in setting up asynchronous communications. You must also configure your DECnet lines, links, and circuits. Setting up a link and circuit for asynchronous connections is the same as when you set up a synchronous link and circuit. The difference occurs when you configure your line in the Modem Connect module. The communications port attribute for the modem connect line has special significance.

To set up a dynamic asynchronous connection, you need to preconfigure the protocol stack. This means that you need to map a routing circuit to a DDCMP logical station. The logical station, in turn, uses a line created with the Modem Connect module that specifies a communications port with either a "floating" line or an explicit line for your dynamic connection. A "floating" line is not tied to a specific terminal device, while an explicit line is tied to a specific device. You must configure the protocol stack (at both ends of the link when using two DECnet-Plus for OpenVMS systems) before you set host to the remote system and switch the dynamic asynchronous line into operation.

A static asynchronous DECnet connection is a permanent connection between two nodes. This type of connection can be made in one of two ways:

• The nodes can be connected by a physical line (a null modem cable) attached to a terminal port at each system. No modems are required. You can communicate with the other system at any time.
• The connection can be made over a dialup line using modems at both ends of the line. For example, your OpenVMS system can establish a static asynchronous connection to a remote node over a telephone line.

Follow the steps outlined in this section to manually establish a static asynchronous connection. For the connection to be successful, the node with which you are creating a DECnet link must also establish an asynchronous DECnet connection with your node. (The line speeds at each end of the connection must be the same.)

1. Log in to the SYSTEM account on your OpenVMS system.
2. DECnet must be running on both nodes for the remaining steps. If not already done, you and the remote system manager must start up the network by entering the following command:

   $ @sys$startup:net$startup

3. Load the asynchronous driver, asydriver.
   Enter the following commands at your terminal (or include them in the sys$manager:systartup_vms.com command procedure before you boot the system):

   $ run sys$system:sysgen SYSGEN> connect asy0/noadapter/driver=asydriver SYSGEN> exit

   
   The asynchronous driver must be loaded before any asynchronous connection can be made.
4. Next, install the asynchronous shareable images required for a static asynchronous connection. Use the following command:

   $ install add sys$library:asyswitch.exe/open/head/share

5. To change a terminal line into a static asynchronous DECnet line, use the DCL command set terminal terminal-port-name with the appropriate qualifiers, where terminal-port-name represents the device where you want to connect the static asynchronous DECnet line (see examples a and b.) If you have more than one terminal attached to your OpenVMS system, you must specify a set terminal command for each terminal line used for a static asynchronous DECnet connection.
   1. Nondialup line: The following command converts the terminal line connected to the port into a DECnet line with no modem control:

      $ set terminal/permanent/nomodem/notype_ahead - _$ /network terminal-port-name

      
      The terminal-port-name, for instance, could be tta0.
   2. Dialup line: The following command converts the terminal line connected to the port (which can be used as a dialup line) into a DECnet line with modem control:

      $ set terminal/permanent/notype_ahead/network/modem - _$ /noautobaud/nohangup terminal-port-name

      
      The terminal-port-name, for instance, could be ttb0.
   
   You can change the line speed by resetting the line to non-network mode with the set terminal/nonetwork command. After you do this, switch the line back to network mode with the set terminal/network command. You cannot use the set command to change the line speed or any other parameters while the line is in network mode.
   You can ensure that these set terminal commands execute automatically each time the network is started in the future. Modify your sys$manager:systartup_vms.com command procedure to include all required set terminal commands after the network starts up but before executing the commands in the next step that configure the modem connect line.
6. Next, configure your line. If the configuration procedures have not already created the Modem Connect module, create it manually before configuring the line. Use the following example to set up the necessary modem connect entities.

   $ run sys$system:ncl ncl> create modem connect line static_asynch - _ncl> communications port async_port_name (1) ncl> set modem connect line static_asynch speed 2400 (2) ncl> enable modem connect line static_asynch

   1. For an asynchronous line or circuit, the communications port attribute, (async_port_name), has one of two formats:
      • devcu as in txa0:
      • dev-c-u as in tx-0-0
      
      where dev-c-u is defined as follows:

      dev	The first two letters of the asynchronous device name (possible values are tt and tx).
      c	A decimal number (0 or a positive integer) designating a device's hardware controller. If the third letter of the device name is A, c equals 0. If the third letter of the device name is B, c equals 1, and so on.
      u	The unit number of the device name; u is always equal to 0 or a positive integer.

      
      For example, dev-c-u would be tx-0-0 for unit txa0:.
   2. The line speeds at both sides of the connection should be the same.
7. Next, configure your data link and routing circuit. For information about configuring your data link and routing circuit, see the chapters on managing network security and network management tasks in DECnet-Plus for OpenVMS Network Management.
8. For security over a dialup connection, run NCL and establish optional routing initialization passwords. For more information about using verifiers, refer to the DECnet-Plus for OpenVMS Network Management guide.

Use the following steps to terminate a static asynchronous connection:

1. Use NCL to disable (turn off) and delete the routing circuit and the static asynchronous line, as follows:

   $ run sys$system:ncl ncl> disable modem connect line static_asynch ncl> disable ddcmp link static_asynch - _ncl> logical station static_asynch ncl> disable ddcmp link static_asynch ncl> disable routing circuit static_asynch ncl> delete modem connect line static_asynch ncl> delete ddcmp link static_asynch - _ncl> logical station static_asynch ncl> delete ddcmp link static_asynch ncl> delete routing circuit static_asynch ncl> exit

2. The following command switches your asynchronous line back to a terminal line:

   $ set terminal/permanent/nonetwork/typeahead terminal_port_name

If the initial set terminal command fails, check that:

• WANDD started up.
• The asydriver loaded (the asy0 device must be present).
• The asyswitch installed.

If the logical station is in the on-starting state, check that:

• The line speeds at both ends of the connection are set to the same value.
• The modem control characteristic of the modem connect line at both ends of the link are the same.
• The routing circuits configured correctly.
• The parity is correct. Asynchronous DECnet requires the parity on the asynchronous line be set to none and the terminal line be set to use 8-bit characters. If you are using a system other than OpenVMS, the terminal line must be set to the correct parity.

If your terminal line cannot be set up as a static asynchronous DDCMP line, check whether the following condition exists:

• If data is stored in a type-ahead buffer, the line appears as a terminal line even if a startup command procedure attempts to set it up as a DDCMP line. This generally occurs when the remote node is running and its asynchronous DDCMP line is on. The DDCMP start messages being transmitted are stored in the type-ahead buffer associated with your terminal line. Before you can start up your line in DDCMP mode, terminate the process that owns your terminal line.

To verify that the asynchronous line is connected properly, check the following:

• For local connections, verify that the cable is a null modem cable.
• For modem connections, verify that the cable is a straight-through cable and that if the modem is put in analog loopback, the circuit comes up with the local node as the adjacent node.
• For both types of connections, verify that the port is operational by resetting it to terminal-type characteristics and plugging in a terminal and logging in.

If your connection is timing out or losing DDCMP packets, you might not have a sufficient number of receive buffers set up on the DDCMP link for the asynchronous line.

For more information about solving problems in your DECnet-Plus network, refer to the DECnet-Plus Problem Solving guide.

A.1.2 Establishing a Dynamic Asynchronous Connection

A dynamic asynchronous DECnet connection is a temporary connection between two nodes, usually over a telephone line through the use of modems. You can switch the line at each end of the connection from a terminal line to a dynamic asynchronous DECnet line. A dynamic asynchronous connection is usually maintained only for the duration of a telephone call.

Dynamic switching of terminal lines to asynchronous DDCMP lines can occur between DECnet-Plus systems or between a DECnet-Plus system and a non DECnet-Plus system. Assuming that both the remote node and the local node are OpenVMS operating systems, the system manager at each node must have loaded the asynchronous driver, asydriver, and installed the shareable images asyswitch and asydynswitch. (If the local node is a personal computer, there is no need to load asydriver and install asydynswitch.) The system manager at the remote node must have enabled the use of virtual terminals on the system. First, the system manager must have enabled virtual terminals by issuing the sysgen connect command. The system manager must also have enabled virtual terminals on the system. The terminal devices, which you plan to use for dynamic connections, should be set up with the /disconnect qualifier.

Setting up a dynamic asynchronous connection involves two distinct sets of steps.

1. At some point, you must configure your dynamic asynchronous line. See Section A.1.2.1 for more information about this.
2. You dynamically switch the line to a DECnet line. See Section A.1.2.2 for more information about this.

Use the following steps to manually set up your dynamic asynchronous line any time prior to the dynamic switch. This example assumes the local OpenVMS node is originating the connection and switching the terminal line on for DECnet use. The connection must be to an OpenVMS node on which you have an account with net$decnetaccess rights.

To set up a dynamic asynchronous connection, you must execute the instructions discussed in this section at both the local and remote OpenVMS systems. If the remote system is a system other than OpenVMS, refer to the remote system's documentation for information about setting up a dynamic asynchronous connection.

1. Log in to the SYSTEM account on your OpenVMS node.
2. DECnet must be running on both nodes for the remaining steps. If not already done, you and the remote system manager must start up the network by entering the following command:

   $ @sys$startup:net$startup

3. Load the asynchronous driver, asydriver.
   Enter the following commands at your terminal (or include them in the sys$manager:systartup_vms.com command procedure before you boot the system):

   $ run sys$system:sysgen SYSGEN> connect asy0/noadapter/driver=asydriver SYSGEN> exit

   
   The asynchronous driver must be loaded before you can make any asynchronous connection.
4. Next, install the asynchronous shareable images. Use the following command:

   $ install add sys$library:asyswitch.exe/open/head/share $ install add sys$library:asydynswitch.exe/open/head/share/protected

   
   The following commands enable the use of virtual terminals for the terminal line that is to be switched, and set the disconnect characteristic for the terminal line. (The virtual terminal capability permits the process to continue running if the physical terminal you are using becomes disconnected.)

   $ run sys$system:sysgen SYSGEN> connect vta0/noadapter/driver=ttdriver SYSGEN> exit $ set terminal/eight_bit/permanent/modem/disconnect terminal-port-name:

   
   terminal-port-name is the name of the terminal port on the remote node to which the dynamic asynchronous connection is made. The terminal-port-name, for instance, could be txa3.
5. After you load asydriver and install the asynchronous shareable images, you need to preconfigure the protocol stack for the dynamic asynchronous line. A protocol stack for a dynamic asynchronous connection is a routing circuit that is mapped to a ddcmp logical station. The ddcmp logical station uses a modem connect line created with the communications port attribute specified as either async or async-terminal_name (for example: async-tx-0-3). You must configure the protocol stack before you switch the dynamic asynchronous line into operation by means of the DCL set terminal command. The following steps explain how to do this.
   If the configuration procedures have not already created the Modem Connect module, create it manually before configuring the line. Use the following example to set up the necessary modem connect entities:

   $ run sys$system:ncl ncl> create modem connect line dynamic_asynch - _ncl> communications port async_port_name (1) ncl> set modem connect line dynamic_asynch speed 2400 ncl> enable modem connect line dynamic_asynch

   1. In dynamic asynchronous connections, you can specify the communications port attribute (async_port_name) in one of two ways when creating the modem connect line entity:
      • async --- When you specify async, a unique number is given to the modem connect line as an "-n" extension to the async name each time a modem connect line with a communications port attribute of ASYNC is created. This creates a "floating" modem connect line, which is not tied to a specific terminal device or unit. For example:

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