Allied Telesis AT-S63 User Manual

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Chapter 33: Encryption Keys
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Section IX: Management Security
Encryption Key Length
When you create a key pair, you have to specify its length in bits. The 
range is 512, the default, to 1,536 bits, in increments of 256 bits. The 
longer the key, the more difficult it is for someone to decipher. If you are 
particularly concerned about the safety of your management sessions, 
you might want to use a longer key length than the default, though the 
default is likely to be sufficient in most situations.
Creating a key is a very CPU intensive operation for the switch. Although 
the switch does not stop forwarding packets between the ports, the 
process can impact the CPU’s handling of network events, such as the 
processing of spanning tree BPDU packets, which can result in 
unexpected and unwanted switch behavior.
A key with the default length should take the switch less than a minute to 
create. Longer keys can take up to 15 minutes. You should take this into 
account when creating a key to minimize the impact to the operations of 
your network. If you intend to create a long key, consider creating it before 
you connect the switch to the network, or during periods of low network 
traffic.