test

SunScreen SKIP User's Guide, Release 1.1

Adding Authorized Systems

Any remote host with which you want to communicate (send or receive data) must be configured using the Add pop-up window.

An authorized host may or may not be using encryption. The Add pop-up window provides four options:

You add hosts to the authorized systems list using the Add button, located at the bottom left of the main window of skiptool.

The valid types of remote hosts that you can add to your ACL are

Caution - Caution -

When setting up SunScreen SKIP, be sure to include any NFS servers and NIS or DNS name servers on the authorized systems list, otherwise your system may hang.

Note -

To avoid problems such as this, a safe approach at the beginning is to add the clear "default" entry. Once you become more comfortable with SKIP configuration, you can remove it.

To determine the servers your system communicates with, use the following commands:

If you do not specify a system that you currently have in use when you enable access control, a menu will come up and ask if you want to add the system. It also checks for multicast routers that are being used for others and adds them to the proposed list of systems to add.

Regardless of the type of system that you are adding to the ACL, you must implement the same policy on both your machine and the entity with which you wish to communicate securely over the intranetworks or internetworks. If you do not configure both systems properly, the packets are silently dropped and it appears as if that particular host does not exist. skiplog is useful in diagnosing this situation.

When you click on the Add button, the Add pop-up window appears. From the menu in this window, you select the type of connection: Host, Network, or Nomadic. Next, use the pull-right menu to set the security level. After you have selected the level of security, the appropriate Properties window becomes available. The Add System Properties window is used to set up the options for the type of encryption used by the host, network, or nomadic system being authorized. Table 3-1shows what type of encryption can be used with hosts, networks, or nomadic systems. The procedures in the sections following the table detail how to set up each encryption option.

Table 3-1 Type of Security Available, by Type of System

Type of System 

Type of Security  

Off (none) 

SKIP  

SKIP (Version 1) 

ESP/AH (manual keying) 

Host 

X 

X 

X 

X 

Network 

X 

X 

X 

X 

Nomadic 

-- 

X 

X 

-- 

Adding a Host or Network with No Encryption

This procedure is used to allow a host or network access to your system without using any encryption.

  1. Click and hold on the Add button at the bottom of the authorized systems list on the skiptool main window.

  2. Select the type of connection being authorized: Host or Network. (Nomadic does not offer this option.)

  3. Pull right on the type of connection and select Off.

    The Add Host properties or Add Network properties dialog box will appear (Figure 3-2).

    Figure 3-2 Add Host/Properties--No Encryption

    Graphic

  4. In the Add Host or Network properties window, enter the name or IP address of the host system to be added to your ACL.

    In the case of a network, you must define the network with the IP address and the netmask.

  5. Click the Apply button.

Setting Up Security for a Host, Network, or Nomadic System

These procedures enable a host, network, or nomadic system access to your system according to the encryption rules set up using one of the procedures below. Remember, both your system and the other system need to use the same properties in order to communicate.

Explanations of the Dialog Box Parameters

The three encryption dialog boxes (SKIP, SKIP Version 1, and ESP/AH) use common set-up parameters, as you can see in Figure 3-3 through Figure 3-10. Explanations of the parameters follow the figures. The procedure follows the explanations.

Figure 3-3 Host--Add SKIP Host Properties

Graphic

Figure 3-4 Host--Add SKIP Version 1 Properties

Graphic

Figure 3-5 Host--Add ESP/AH Host Properties

Graphic

Figure 3-6 Network--Add SKIP Network Properties

Graphic

Figure 3-7 Network--Add SKIP Version 1 Properties

Graphic

Figure 3-8 Network--Add ESP/AH (Manual Keying) Network Properties

Graphic

Figure 3-9 Nomadic--Add SKIP Properties (Nomadic)

Graphic

Figure 3-10 Nomadic--Add SKIP Version 1 (Nomadic)

Graphic