SMC Networks SMC TigerStack III SMC6824MPE - Manual (Page 120)

C
ONFIGURING THE
S
WITCH
3-70
3. Import Client’s Public Key to the Switch – Use the copy tftp public-key
command (page 4-84) to copy a file containing the public key for all
the SSH client’s granted management access to the switch. (Note that
these clients must be configured locally on the switch via the User
Accounts page as described on page 3-59.) The clients are
subsequently authenticated using these keys. The current firmware
only accepts public key files based on standard UNIX format as
shown in the following example for an RSA Version 1 key:
1024 35 1341081685609893921040944920155425347631641921872958921143173880
055536161631051775940838686311092912322268285192543746031009371877211996
963178136627741416898513204911720483033925432410163799759237144901193800
609025394840848271781943722884025331159521348610229029789827213532671316
29432532818915045306393916643 [email protected]
4. Set the Optional Parameters – On the SSH Settings page, configure the
optional parameters, including the authentication timeout, the number
of retries, and the server key size.
5. Enable SSH Service – On the SSH Settings page, enable the SSH server
on the switch.
6. Challenge-Response Authentication – When an SSH client attempts to
contact the switch, the SSH server uses the host key pair to negotiate a
session key and encryption method. Only clients that have a private
key corresponding to the public keys stored on the switch can access.
The following exchanges take place during this process:
a. The client sends its public key to the switch.
b. The switch compares the client's public key to those stored in
memory.
c. If a match is found, the switch uses the public key to encrypt a
random sequence of bytes, and sends this string to the client.
d. The client uses its private key to decrypt the bytes, and sends the
decrypted bytes back to the switch.
e. The switch compares the decrypted bytes to the original bytes it
sent. If the two sets match, this means that the client's private key
corresponds to an authorized public key, and the client is
authenticated.