little Question concerning to SNMP runtime (delay)

[tecker2010]

Hi,
I only want to how Cacti establish the runtimes of SNMP requests. It' s the value at the device named current (ms).
Is it only the difference between SNMP request and SNMP response?
The background why I am asking is because I have times up to 1500ms (average 1000ms). Is that because I am using SNMPv3 with authentification (SHA) and encryption (DES) or does it refer to the switches/network?

Thx for help.
Best regards