3Com TP-1610, Руководство пользователя

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V6100 and V7122 User Guide
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Table Indices
Each line in a table must be unique. Therefore, each table defines one or more Index fields.
The combination of the Index fields determines the 'line-tag'. Each line-tag appears only
once.
In the example provided in Table 64 there is only one Index field. This is the simplest way to
mark lines.
In the example provided in Table 65 there are three Index fields. This more complicated
method is a result of the application it represents.
Table Permissions
Each column has a 'permission' attribute that is applied to all instances in the column. This
permission determines if and when a field can be modified. Several permissions can be
applied to each column.
The following permissions are available:
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Read - The value of the field can be read.
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Write - The value of the field can be modified.
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Create - A value for the field must be provided at creation time (the default
values, set to all fields, determine the initial values).
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Maintenance Write - The value of the field can only be modified when the entity
represented by the line is in maintenance state (each table includes rules that determine
when it is in maintenance state).
In the example in Table 64 it is assumed that the columns ‘User Name’ and ‘User Password’
have Read-Create permissions. The column ‘Time Connected’ has a Read permission, and
the column ‘Permissions’ has Read-Create-Maintenance Write permissions.
Dynamic Tables vs. Static Tables
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Static Tables - Static tables don’t support adding new lines or removing (deleting)
existing lines. All lines in a Static table are pre-configured with default values. Users can
only modify the values of the existing lines. After reset, all lines in a Static table are
available.
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Dynamic Tables - Dynamic tables support adding and removing lines. They are always
initialized as empty tables with no lines. Users should add lines to a Dynamic table via
the
ini file or at run-time via the Embedded Web Server for example.
Certain dynamic tables may initialize a line (or more) at start-up. If so, it is
explained in the specific table's documentation.