D-Link DGS-3700 Switch User Manual


 
DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet Switch User Manual
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Password This parameter should be chosen if the administrator wishes to use an
administrator-defined password for authentication. Upon entry of this parameter, the Switch
will prompt the administrator for a password, and then to re-
type the password for
confirmation.
Public KeyThis parameter should be chosen if the administrator wishes to use the
publickey on a SSH server for authentication.
Host Name
Enter an alphanumeric string of no more than 32 characters to identify the remote SSH user.
This parameter is only used in conjunction with the Host Based choice in the Auth. Mode
field.
Host IP
Enter the corresponding IP address of the SSH user. This parameter is only used in
conjunction with the Host Based choice in the Auth. Mode field.
Click Apply to implement changes made.
NOTE: To set the SSH User Authentication parameters on the Switch, a User Account
must be previously configured. For more information on configuring local User Accounts on
the Switch, see the User Accounts section of this manual located in the Configuration
section.
Access Authentication Control
The TACACS/XTACACS/TACACS+/RADIUS commands allow users to secure access to the Switch using the
TACACS/XTACACS/TACACS+/RADIUS protocols. When a user logs in to the Switch or tries to access the
administrator level privilege, he or she is prompted for a password. If TACACS/XTACACS/TACACS+/RADIUS
authentication is enabled on the Switch, it will contact a TACACS/XTACACS/TACACS+/RADIUS server to verify the
user. If the user is verified, he or she is granted access to the Switch.
There are currently three versions of the TACACS security protocol, each a separate entity. The Switch's software
supports the following versions of TACACS:
TACACS (Terminal Access Controller Access Control System) - Provides password checking and
authentication, and notification of user actions for security purposes utilizing via one or more centralized
TACACS servers, utilizing the UDP protocol for packet transmission.
Extended TACACS (XTACACS) - An extension of the TACACS protocol with the ability to provide more
types of authentication requests and more types of response codes than TACACS. This protocol also uses
UDP to transmit packets.
TACACS+ (Terminal Access Controller Access Control System plus) - Provides detailed access control
for authentication for network devices. TACACS+ is facilitated through Authentication commands via one or
more centralized servers. The TACACS+ protocol encrypts all traffic between the Switch and the TACACS+
daemon, using the TCP protocol to ensure reliable delivery
In order for the TACACS/XTACACS/TACACS+/RADIUS security function to work properly, a
TACACS/XTACACS/TACACS+/RADIUS server must be configured on a device other than the Switch, called an
Authentication Server Host and it must include usernames and passwords for authentication. When the user is
prompted by the Switch to enter usernames and passwords for authentication, the Switch contacts the
TACACS/XTACACS/TACACS+/RADIUS server to verify, and the server will respond with one of three messages:
The server verifies the username and password, and the user is granted normal user privileges on the Switch.
The server will not accept the username and password and the user is denied access to the Switch.
The server doesn't respond to the verification query. At this point, the Switch receives the timeout from the
server and then moves to the next method of verification configured in the method list.
The Switch has four built-in Authentication Server Groups, one for each of the TACACS, XTACACS, TACACS+ and
RADIUS protocols. These built-in Authentication Server Groups are used to authenticate users trying to access the
Switch. The users will set Authentication Server Hosts in a preferable order in the built-in Authentication Server
Groups and when a user tries to gain access to the Switch, the Switch will ask the first Authentication Server Hosts for
authentication. If no authentication is made, the second server host in the list will be queried, and so on. The built-in
Authentication Server Groups can only have hosts that are running the specified protocol. For example, the TACACS
Authentication Server Groups can only have TACACS Authentication Server Hosts.