I'm working on snmpv3. In the RFC and internet I haven't seen any documentation regarding how the encryption and hashing algorithms exchanged between the entities. I wonder will there be any cipher negotiation happens in SNMPv3 or both parties should agree upon a specific set of algorithms prior to the communication and use them?
I wonder whether you are reading the proper RFC documents. For SNMP v3 there is no cipher negotiation at all. You have to know exactly how a device is configured so as to manage it.
It is not something like HTTP over SSL.