Spectracom VersaSync User Manual page 73

You can create individual RSA and DSA Host Public/Private Key pairs. Host keys must first be
deleted before new Host Keys can be created.
VersaSync units have their initial host keys created at the factory. RSA host key sizes can vary
between 768 and 4096 bits. The recommended key size is 1024. Though many key sizes are
supported, it is recommended that users select key sizes that are powers of 2 or divisible by 2.
The most popular sizes are 768, 1024, and 2048. Large key sizes of up to 4096 are sup-
ported, but may take 10 minutes or more to generate. DSA keys size support is limited to 1024
bits.
Host keys are generated in the background. Creating RSA and DSA keys, each with 1024 bits
length, typically takes about 30 seconds. Keys are created in the order of RSA, DSA, RSA.
When the keys are created, you can successfully make SSH client connections. If the unit is
rebooted with host key creation in progress, or the unit is booted and no host keys exist, the
key generation process is restarted. The key generation process uses either the previously spe-
cified key sizes or, if a key size is undefined, the default key bit length size used is 2048. A key
with a zero length or blank key size field is not created.
The SSH client utilities SSH, SCP, and SFTP allow for several modes of user authentication.
SSH allows you to remotely login or transfer files by identifying your account and the target
machine's IP address. As a user you can authenticate yourself by using your account password,
or by using a Public Private Key Pair.
It is advisable to keep your private key secret within your workstation or network user account,
and provide the VersaSync a copy of your public key. The modes of authentication supported
include:
SSH using public/private key authentication is the most secure authenticating method for SSH,
SCP or SFTP sessions.
You are required to create private and public key pairs on your workstation or within a
private area in your network account. These keys may be RSA or DSA and may be any key bit
length as supported by the SSH client tool. These public keys are stored in a file in the
directory named
by the optional comment with only one key per line.
Changing Key Length Values
You may change the key length of the RSA, DSA, ECDSA type host keys.
To change the key length of a host key:
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2 VersaSync User Manual Rev. 6.0
Either Public Key with Passphrase or Login Account Password
Login Account Password only
Public Key with Passphrase only
authorized_keys
Note: The file format, line terminations, and other EOL or EOF characters should
correspond to UNIX conventions, not Windows.
2.7 Configuring Network Settings
. The file is to be formatted such that the key is followed
.ssh
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