13 Screen Set Configuration
Chapter 13, Screen Set Configuration, contains the procedures necessary to configure screen sets.
Introduction
A screen set is a gateway screening table containing a list of rules, or screening references. The screening references indicate the screening action that is to be performed on a message in a specific linkset. These screening references are configured in Allowed Affected Point Code (AFTPC) Screen Configuration through Allowed Originating Point Code (OPC) Screen Configuration. The screen set is assigned to a linkset. When the gwsa=on linkset parameter is specified for a specific linkset, all the messages on that linkset will be screened by the gateway screening feature based on the screening references contained in the screen set. For more information of the linkset parameters used for the gateway screening feature, go to the Gateway Screening States section, or to the ent-ls or chg-ls command descriptions in Commands User's Guide.
Automatic Destination Field Screening
Network management messages can be screened
automatically by gateway screening without configuring an Allowed Affected
Destination Field screen. The
destfld=yes parameter specified with
the
ent-scrset or
chg-scrset commands turns on automatic
screening of the affected destination point code (see
Figure 7-4)
in the network management messages. Network management messages contain the
value 0 in the service indicator field of the SIO. The network management
messages are screened against the routing table, the EAGLE’s point code, and
capability point codes. If the affected destination point code matches the
EAGLE’s point code, capability point codes, or point codes in the routing
table, the message is allowed into the EAGLE. The automatic screening is
applied after the last screen in the screening process, containing the
nsfi=stop parameter, for that screen
set.
These network management messages are automatically screened by gateway screening: TFP, TFA, TFR, TFC, UPU, SRST (RSP, RSR). All other network management messages are allowed into the EAGLE.
Adding a Screen Set
This procedure is used to add a screen set to the
database using the
ent-scrset command. The parameters
used by the
ent-scrset command are shown in the
Gateway Screening Attributes
section. The general rules that apply to configuring gateway screening entities
are shown in the
Gateway Screening Configuration
section.
A maximum of 255 screen sets can be configured in the
database. If the database contains 255 screen sets, any attempt to add another
screen set with the
ent-scrset command will be rejected.
If the database contains 255 screen sets, and you wish to add another screen
set, a current screen set must be removed or changed. To remove a screen set,
perform the
Removing a Screen Set
procedure. To change an existing screen set, perform the
Changing a Screen Set
procedure.
The examples in this procedure are used to add the screen set data shown in Table 13-1 and based on the example configurations shown in Figure 2-3 through Figure 2-9.
Table 13-1 Example Gateway Screening Screen Set Configuration Table
| Screen Set Name | Next Screening Function Identifier | Next Screening Reference | DESTFLD |
|---|---|---|---|
| gws1 | opc | gws4 | No |
| gws2 | blkopc | gws5 | No |
| ls01 | sio | ls02 | Yes |
| wrd1 | dpc | iec | Yes |
| fld1 | opc | fld2 | No |
| isp1 | opc | isp1 | No |
| tup1 | opc | tup1 | No |
The screen set can reference one of the following screens.
- Allowed OPC
- Blocked OPC
- Allowed SIO
- Allowed DPC
- Blocked DPC
Verifying the Gateway Screening Configuration
Enter the following commands to verify that these screens are in the database.
rtrv-scr-opc:all=yesrtrv-scr-blkopc:all=yesrtrv-scr-sio:all=yesrtrv-scr-dpc:all=yesrtrv-scr-blkdpc:all=yes
Gateway Screening Configuration Procedures
If the desired screen is not in the database, perform one of these procedures to add the desired screen to the database or change an existing screen in the database.
Figure 13-1 Add a Screen Set - Sheet 1 of 3
Figure 13-2 Add a Screen Set - Sheet 2 of 3
Figure 13-3 Add a Screen Set - Sheet 2 of 3
Removing a Screen Set
This procedure is used to remove a screen set from the
database using the
dlt-scrset command. The parameters
used by the
dlt-scrset command are shown in the
Gateway Screening Attributes
section. The general rules that apply to configuring gateway screening entities
are shown in the
Gateway Screening Configuration
section.
The example in this procedure removes the screen set
gws1 from the database.
Figure 13-4 Remove a Screen Set
Changing a Screen Set
This procedure is used to change the attributes of a
screen set in the database using the
chg-scrset command. The parameters
used by the
chg-scrset command are shown in the
Gateway Screening Attributes
section. The general rules that apply to configuring gateway screening entities
are shown in the
Gateway Screening Configuration
section.
The example in this procedure is used to change screen
set
ls01 to screen set
ls05 with the
nsfi=blkopc and
nsr=ls08.
If the screen set name is being changed, the new screen set name cannot already exist in the database.
The screen set can reference one of the following screens.
- Allowed OPC
- Blocked OPC
- Allowed SIO
- Allowed DPC
- Blocked DPC
Verifying the Gateway Screening Configuration
Enter the following commands to verify that these screens are in the database.
rtrv-scr-opc:all=yesrtrv-scr-blkopc:all=yesrtrv-scr-sio:all=yesrtrv-scr-dpc:all=yesrtrv-scr-blkdpc:all=yes
Gateway Screening Configuration Procedures
If the desired screen is not in the database, perform one of the following procedures to add the desired screen to the database or change an existing screen in the database.
Figure 13-5 Change a Screen Set - Sheet 1 of 3
Figure 13-6 Change a Screen Set - Sheet 2 of 3
Figure 13-7 Change a Screen Set - Sheet 3 of 3