R3303-HP HSR6800 Routers Security Configuration Guide

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• Password history
With this feature enabled, the system maintains certain entries of passwords that a user has used.
When a user changes the password, the system checks the new password against the history
passwords and the current password. The new password must be different from the used ones by
at least four characters and the four characters must not be the same. Otherwise, the user will fail
to change the password and the system displays an error message.
You can set the maximum number of history password records for the system to maintain for each
user. When the number of history password records exceeds your setting, the latest record
overwrites the earliest one.
• Login attempt limit
Limiting the number of consecutive failed login attempts can effectively prevent password
guessing.
If an FTP or VTY user fails authentication due to a password error, the system adds the user to a
password control blacklist. If a user fails to provide the correct password after the specified
number of consecutive attempts, the system takes action as configured:
{ Prohibiting the user from logging in until the user is removed from the password control blacklist
manually.
{ Allowing the user to try continuously and removing the user from the password control blacklist
when the user logs in to the system successfully or the blacklist entry times out (the blacklist entry
times out after 1 minute).
{ Prohibiting the user from logging in within a configurable period of time, and allowing the user
to log in again after the period of time elapses or the user is removed from the password control
blacklist.
A password control blacklist can contain up to 1024 entries.
A login attempt using a wrong username will undoubtedly fail but the username will not be added
into the password control blacklist.
Users accessing the system through the console or AUX interface are not blacklisted, because the
system is unable to obtain the IP addresses of these users and these users are privileged and
therefore relatively secure to the system.
• Password composition policy
A password can be a combination of characters from the following four types:
{ Uppercase letters A to Z
{ Lowercase letters a to z
{ Digits 0 to 9
{ Special characters. For information about special characters, see the password command in
Security Command Reference.
Depending on the system security requirements, you can set the minimum number of character
types a password must contain and the minimum number of characters for each type, as shown
in Table 10.
Table 10 Password c
omposition policy
Password combination
level
Minimum number of
character t
yp
es
Minimum number of characters for
each t
yp
e
Level 1 One One
Level 2 Two One