Security Management Guide (G06.29+, H06.08+, J06.03+)

Concerns for the System Administration Team
Security Management Guide — 522283-021
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Managing the Network User IDs
Managing the Network User IDs
Handling network user IDs requires careful planning and cooperation among (possibly)
geographically separated organizations. The Guardian environment requires that
network user IDs have the same user name and user ID on all affected nodes. This
condition requires advance networkwide planning.
You might reserve a range of group numbers (for example, 200 to 255) for network
user IDs, and assign network user IDs from these administrative groups. Then decide
on the networkwide names for those groups on an as-needed basis, maybe even
reserving a particular initial letter (such as N) for network groups. Also, you might
designate a particular organization to own each group name and group ID and make
that organization responsible for controlling the allocation of user IDs within its group.
Security Precautions
Treat a network user ID like a privileged ID because the network user has more access
than users confined to local nodes. If an intruder can access the ID, the intruder gains
access to virtually any N-secured file on the network, not just the N-secured files on the
nodes for which the user has matching remote passwords.
Encrypting Data Between Nodes
With the standard network software, data moves between nodes without encryption.
However, you might want to consider the Atalla A-5000 High Speed Security Module
for encryption of sensitive data. For more information, see the High Performance
Security Module (HPSM) User’s Guide.
Communicating With Other System Managers
In a distributed system management environment, an intruder can obtain sensitive
information by pretending to be a member of the system administration team at
another site (for example, a system manager or a newly hired or temporary operator).
If your organization spans a large physical area, authenticate sensitive
communications. Y
ou need to authenticate communications that come by phone or by
interplant, standard, or electronic mail.
Remember that a complete authentication scheme includes ways to handle routine
operations, emergencies, and temporary personnel.
An intruder can send an electronic mail message that appears to be from a privileged
person requesting a specific action. Such a message might be sent from the privileged
person’s unattended terminal, or the message header might be altered to appear as
though the privileged person sent it. Depending on the risk involved, delay performing
the requested service until you can verify the sender.
Acknowledge sensitive requests immediately (by phone or electronic letter). It is
unlikely that the intruder can be in the right place at the right time to intercept a reply or
confirmation. Investigate an out-of-place confirmation before damage is done. For