[AGENT++] v3MP class question

[Jochen Katz]

Hi,

> As I understand,(correct me if I'm wrong)  v3MP class is used only with v3
> of snmp.

yes, but if _SNMPv3 is defined, a v3MP object has to be created.

> And it is used to store engineID-s of another agents? So this one (agent)
> would know about others, where they are and who are they.

yes.

> But how does the agent find out about others, is this user input, or
> something else. Is there some example that deals only with v3MP class.

The mapping host/port to engine id is done atomatically, when a v3
message is sent to host/port (unless engine id discovery is disabled).
If you want to have the highest possible level of security, you have to
disable engine id discovery and add all engine ids to the v3MP yourself.

Under normal operation, the only functions you need from v3MP is the
constructor and the get_usm() function. So there is no example beside
the usage in the snmp++/agent++ examples.

> And for what purposes is v3MP used. (I mean in application).

It implements the message processing for SNMPv3 messages as defined in
rfc3412.

> Oh yeah and, what exactly is bootCounter (getBootCounter saveBootCounter)
> and why is it important? (I didn't find any docs on it).

Although it is an RFC, rfc3414 has a really good explanation of the
engine boot counter in section 2.2.2.

You can use the get/saveBootCounter() functions to store it in a file,
but you can also use your own functions to store it elsewhere (e.g. in
the registry on windows).

Regards,
  Jochen