isoapplications(5) — Macro Packages and Conventions

Name

isoapplications − used to manage the OSI application entity database

Syntax

/etc/isoapplications

Description

Once you install the FTAM and Virtual Terminal software, you need to run the /usr/sbin/osiapplsetup procedure to configure addressing information that allows the local FTAM and VT initiators to communicate with local listeners or remote applications.

The /usr/sbin/osiapplsetup procedure adds addressing information to the /etc/isoapplications file.

Two types of information can be stored in this file:

1. Addressing information about remote applications, local listeners, and source aliases (Address Format.)

2. Information that allows retrieval of the necessary addressing information from the X.500 Directory (Distinguished Name and Pattern Formats.)

The /etc/isoapplications file can contain information exclusively from the first category, information exclusively from the second category, or information from both categories.

The retrieval of addressing information from the X.500 Directory is optional. The FTAM and Virtual Terminal software does not require that the DEC X.500 Directory Service software be installed in order to function properly. If you would like to use the FTAM and Virtual Terminal software in conjunction with the DEC X.500 Directory Service product, then you must have the following DEC X.500 Directory Service subsets installed on your system. These subsets are not packaged with DECnet/OSI for Digital UNIX

DXDABASEnnn - DEC X.500 Base

nnn is the product version number.

Additionally, if you would like to register the addresses of your local FTAM and Virtual Terminal listeners in the X.500 Directory, then you must also have the following subset installed:

DXDADXIMnnn - DEC X.500 Admin. Facility

The rest of the documentation assumes that you are familiar with basic X.500 concepts and terminology. For additional information on X.500, refer to DEC X.500 Directory Service Management.

The /etc/isoapplications file is readable by all, but it can be written to only by a superuser. The database entries can be modified using any text editor; however, the entries must conform to the Address, Distinguished Name, or Pattern formats.

Every entry in /etc/isoapplications has one of three formats:

•Address format

•Distinguished Name format

•Pattern format

Each format of entry contains an alias field and an application-name field. An alias is a short name that refers to an instance of FTAM or VT on a particular system. You are prompted for the value of the alias when you run the /usr/bin/osiapplsetup procedure. In the /etc/isoapplications file, the alias expands either to a full OSI address, or to an X.500 Distinguished Name. Aliases do not have to be unique in /etc/isoapplications.

The aliases used in /etc/isoapplications do not have to correspond to node names because they may also be references to applications. Also, users specify these aliases within commands; therefore, a brief alias name is easier to use.

The order of the entries in /etc/isoapplications is significant.

Aliases may not contain the following characters:

•pound sign (#)

•slash (/)

•colon (:)

•backslash (\)

Aliases in the /etc/isoapplications file must be separated from the remaining fields by white space. The other fields must be enclosed by colons (:).

The value of the application-name field indicates the OSI Application with which the entry is associated. The value of this field is either FTAM or VT.

The ADDRESS Format

Entries of the Address format take the following form:

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

A field that is not required can be omitted, but the delimiters (:) must be included. For example, if ap-title is not required, the following entry for FTAM might be specified:

remote_system :FTAM::2:psap.ssap.tsap.%x4145418715004108002B0DC29621:

For VT, the following entry might be specified:

remote_system :VT::2:psap.ssap.tsap.%x4145418715004108002B0DC29621:

The following characters have special purposes in the database:

•The pound sign (#) is used for comments and can be located anywhere in the file.

•The backslash (\) is used at the end of a line as a continuation character.

Component descriptions in the Address format entry:

alias Name that you intend to use when referring to a system. The alias is followed by white space (a space or a tab). However, it must be delimited from the other fields with a colon. This field is mandatory.

appl-name
Name of the OSI application which will use the address. This component of the entry allows the same alias to be used for multiple applications. Thus, the alias serchr could appear twice in the /etc/isoapplications file, once for FTAM and once for Virtual Terminal. The appl-name is FTAM for FTAM, and VT for Virtual Terminal.

ap-title
Application-process title by which the remote application is known (FTAM or VT). This field is optional. Object identifier values are the valid values for this field.

ae-qualifier
Application-entity qualifier that helps to further distinguish the AP title. This optional field is an integer field.

psel Presentation service access point selector. This optional value can be any string or hexadecimal value.

ssel Session service access point selector. This optional value can be any string or hexadecimal value.

tsel Transport service access point selector. For aliases representing remote systems, this value can be any string or hexadecimal value. The TSEL must be unique for each responder on the local system.

nsap Network service access point. The NSAP can be either an OSI address or an Internet address. If you use an Internet address, use a 4-byte address followed by a port number. For example, the address could be 120.0.0.1.102, where 120.0.0.1 is the 4-byte address and .102 is the port number. Additional information on Internet addresses and port designations can be found in the Digital UNIX System and Network Management Guide. For a remote system, you must ask the manager of the remote system or the network manager for this information. For the local system, use the ncl show osi transport local nsap command as explained in your DECnet/OSI NCL documentation.

transport-options
Selectable transport options for each NSAP specified in the database entry. Including transport options information is optional. Enter all transport option names in lowercase letters.

Values of the transport options are:

transport-provider
Either osi or rfc1006. If you specify rfc1006, you must use an Internet address for the NSAP. Default is osi.

transport-template
The name of the transport characteristics, such as CONS or CLNS. Default is default.

The value for the SAP selectors can include character strings or octet strings. Octet strings must be preceded by %x (or %X). If a particular selector is not required, the delimiter (.) must still be included. For example, if the SSEL is not required, then the format of SAP selectors might resemble the following: PSAP..TSAP.NSAP

Using Transport Options

FTAM and Virtual Terminal each use the transport options information in the following ways:

•If you specify more than one NSAP with transport options, FTAM and VT attempt to make remote connections to the NSAP and its transport options in the order in which they appear in the ISO application entity database.

•If you specify a transport template, remember that it points to a network template. It is important that your templates are properly configured. Refer to your Network Management documentation for information about creating templates.

Use the Network Control Language (NCL) osi transport template entity to create and manage transport templates.

The following example shows how you can use the nsap and transport-options components to specify multiple addresses and transport options for a remote FTAM application:

remote_system :FTAM::2:psap.ssap.%x0001.%x4945418715004108002B0DC29621,\
                                        provider=osi,template=default;\
                                        %x47004AA000400351121,\
                                        provider=osi,template=cons;\
                                        120.0.0.1.102,provider=rfc1006:

The following occurs in these examples:

1. The OSI application (FTAM or VT) uses the selectors psap.ssap.tsap.%x4945418715004108002B0DC29621 with its corresponding transport options to attempt a remote connection.

2. If the connection request fails, the application makes a second remote connection request using %x47004AA000400351121 with its corresponding transport options.

3. If this second request fails, the application attempts a third remote connection request using the Internet address 120.0.0.1.102 with its corresponding transport options.

4. If this request fails, the application stops making connection requests since there are no other NSAPs specified for the alias.

The DISTINGUISHED NAME Format

Entries of the Distinguished Name format take the following form:

alias :application-name:transport_template_list:x500_distinguished_name:

The application-name field contains the name of the application associated with the entry. The value of this field can be either FTAM or VT.

The value of the transport_template_list field lists the names of the transport templates to use when communicating with the application identified by the X.500 Distinguished Name. The transport_template_list takes the following form:

template=template1,template2,...:

Unlike the Address format, the transport-provider option does not have to be specified for the Distinguished Name format.

The x500_distinguished_name field contains an X.500 Distinguished Name. The Distinguished Name uniquely identifies a particular FTAM or Virtual Terminal application, and is associated with a presentation address which in turn is information required by FTAM and VT. The Distinguished Name is used to query the X.500 Directory to obtain the associated presentation address.

The templates are used in conjunction with the presentation address of the application as returned by the X.500 Directory. For example, the presentation address of the application may contain more than one NSAP. In establishing a connection with the application, the first template will be used with the first NSAP in the presentation address. If the connection attempt fails, then the first template will be used with the next NSAP in the presentation address. If there are no more NSAPs to try, the next template in the list of templates will be used with the first NSAP in the presentation address, and so on, until a connection is established with the application.

For example, a Distinguished Name entry in /etc/isoapplications looks like this:

foo :VT:template=cons/c=us/o=widgetco/cn=alias/cn=vt:

The PATTERN Format

Entries of the Pattern format take the following form:

∗ :application-name:transport_template_list:incomplete_distinguished_name:

The asterisk (∗) is a special form of the alias. It is considered to match all input provided to the FTAM and VT commands.

The incomplete_distinguished_name also contains one or more asterisks (∗). At runtime, each asterisks is replaced by the input provided to the FTAM and VT commands, thereby creating a complete X.500 Distinguished Name. For FTAM, usernames and passwords are not included in any of the substitutions.

This resulting Distinguished Name uniquely identifies a particular FTAM or Virtual Terminal application, and is associated with a presentation address that is required by FTAM and VT to establish an association. This Distinguished Name is used to query the X.500 Directory to obtain the associated presentation address.

The application-name field contains the name of the application associated with the entry. The value of this field can be either FTAM or VT.

The value of the transport_template_list field lists the transport templates to be used when communicating with the application identified by the X.500 Distinguished Name. The transport_template_list takes the following form:

template=template1,template2,...:

Unlike the Address format, the transport-provider option does not have to be specified for the Pattern format.

The templates are used in conjunction with the presentation address of the application as returned by the X.500 Directory. For example, the presentation address of the application may contain more than one NSAP. In establishing a connection with the application, the first template will be used with the first NSAP in the presentation address. If the connection attempt fails, then the first template will be used with the next NSAP in the presentation address. If there are no more NSAPs to try, the next template will be used with the first NSAP in the presentation address, and so on, until a connection is established with the application.

For example, a Pattern entry in /etc/isoapplications may look like the following:

∗ :VT:template=default:/c=us/o=widgetco/cn=∗/cn=vt:

The user-provided alias replaces every occurrence of the asterisk (∗) in the Pattern entry. The resulting Distinguished Name is used to query the X.500 Directory to obtain the presentation address associated with the application identified by the Distinguished Name.

Managing the /etc/isoapplications Database

The /usr/sbin/osiapplsetup procedure adds information to the /etc/isoapplications file by prompting the user for the appropriate information. The /etc/isoapplications file can also be modified by using a text editor.

Restrictions

This file is readable by all, but it can be written to only by a superuser.

The following characters have special purposes in the database.