NAME

       snmpa_mpd - Message Processing and Dispatch module for the SNMP agent

DESCRIPTION

       The  module snmpa_mpd implements the version independent Message Processing and Dispatch functionality in
       SNMP for the agent. It is supposed to be used from a Network Interface process (Definition of  Agent  Net
       if).

EXPORTS

       init(Vsns) -> mpd_state()

              Types:

                 Vsns = [Vsn]
                 Vsn = v1 | v2 | v3

              This  function  can  be called from the net_if process at start-up. The options list defines which
              versions to use.

              It also initializes some SNMP counters.

       process_packet(Packet, TDomain, TAddress, State, NoteStore, Log) -> {ok,  Vsn,  Pdu,  PduMS,  ACMData}  |
       {discarded, Reason} | {discovery, DiscoPacket}
       process_packet(Packet,  TDomain, TAddress, LocalEngineID, State, NoteStore, Log) -> {ok, Vsn, Pdu, PduMS,
       ACMData} | {discarded, Reason} | {discovery, DiscoPacket}

              Types:

                 Packet = binary()
                 TDomain = snmpUDPDomain
                 TAddress = {Ip, Udp}
                 LocalEngineID = string()
                 Ip = {integer(), integer(), integer(), integer()}
                 Udp = integer()
                 State = mpd_state()
                 NoteStore = pid()
                 Log = snmp_log()
                 Vsn = 'version-1' | 'version-2' | 'version-3'
                 Pdu = #pdu
                 PduMs = integer()
                 ACMData = acm_data()
                 Reason = term()
                 DiscoPacket = binary()

              Processes an incoming packet. Performs authentication and  decryption  as  necessary.  The  return
              values should be passed the agent.

          Note:
              Note  that  the use of the LocalEngineID argument is only intended for special cases, if the agent
              is to "emulate" multiple EngineIDs! By default, the agent uses  the  value  of  SnmpEngineID  (see
              SNMP-FRAMEWORK-MIB).

       generate_response_msg(Vsn, RePdu, Type, ACMData, Log) -> {ok, Packet} | {discarded, Reason}
       generate_response_msg(Vsn,  RePdu,  Type,  ACMData,  LocalEngineID,  Log)  ->  {ok, Packet} | {discarded,
       Reason}

              Types:

                 Vsn = 'version-1' | 'version-2' | 'version-3'
                 RePdu = #pdu
                 Type = atom()
                 ACMData = acm_data()
                 LocalEngineID = string()
                 Packet = binary()

              Generates a possibly encrypted response packet to be sent to the network. Type is the #pdu.type of
              the original request.

          Note:
              Note that the use of the LocalEngineID argument is only intended for special cases, if  the  agent
              is  to  "emulate"  multiple  EngineIDs!  By default, the agent uses the value of SnmpEngineID (see
              SNMP-FRAMEWORK-MIB).

       generate_msg(Vsn, NoteStore, Pdu, MsgData, To) -> {ok, PacketsAndAddresses} | {discarded, Reason}
       generate_msg(Vsn, NoteStore, Pdu, MsgData, LocalEngineID, To) -> {ok, PacketsAndAddresses} |  {discarded,
       Reason}

              Types:

                 Vsn = 'version-1' | 'version-2' | 'version-3'
                 NoteStore = pid()
                 Pdu = #pdu
                 MsgData = msg_data()
                 LocalEngineID = string()
                 To = [dest_addrs()]
                 PacketsAndAddresses = [{TDomain, TAddress, Packet}]
                 TDomain = snmpUDPDomain
                 TAddress = {Ip, Udp}
                 Ip = {integer(), integer(), integer(), integer()}
                 Udp = integer()
                 Packet = binary()

              Generates a possibly encrypted request packet to be sent to the network.

              MsgData  is  the  message  specific  data  used  in  the SNMP message. This value is received in a
              send_pdu or send_pdu_req message from the agent. In SNMPv1 and SNMPv2c, this message data  is  the
              community  string.  In  SNMPv3,  it  is  the  context information. To is a list of the destination
              addresses and their corresponding security parameters.  This  value  is  also  received  from  the
              requests mentioned above.

          Note:
              Note  that  the use of the LocalEngineID argument is only intended for special cases, if the agent
              is to "emulate" multiple EngineIDs! By default, the agent uses  the  value  of  SnmpEngineID  (see
              SNMP-FRAMEWORK-MIB).

       discarded_pdu(Variable) -> void()

              Types:

                 Variable = atom()

              Increments the variable associated with a discarded pdu. This function can be used when the net_if
              process receives a discarded_pdu message from the agent.

Ericsson AB                                         snmp 4.25                                    snmpa_mpd(3erl)