Here is a possible starting point ..

sub decode_submit_v4 {
    my $pdu = shift;
    ($pdu->{message_class},     # 1 (2)
     $pdu->{source_addr_ton},   # 2 (1)
     $pdu->{source_addr_npi},   # 3 (1)
     $pdu->{source_addr},       # 4 (n+1)
     ) = unpack 'nCCZ*', $pdu->{data};
    my $len = 2    + 1 + 1 + length($pdu->{source_addr}) + 1;

    ($pdu->{number_of_dests}) = unpack 'N', substr($pdu->{data}, $len)
+;
    $len += 4;
    #warn "a decode_submit $len ($pdu->{number_of_dests}): ".hexdump(s
+ubstr($pdu->{data}, $len));
    ....
[download]

Sorry, still not quite get the idea of your example. Is this the server code? How does it related to the APIs in Net::SMPP? What will be a smpp client look like? Thanks Sam

My suggestion was to copy some of the code from the Net/SMPP.pm module into your server script. You would NOT be useing NET::SMPP in the server code, so it is not related to the API.

Since you already have a mechanism (accept from IO::Socket) to receive packets, and all you requested was how to decode them, you could pass the received packet into the sample sub above, and have it decoded for you.

In a similar manner, you would need to construct a response packet, and send it to the client.

Hope this helps. Not having studied the SMPP protocol, I could not estimate the level of difficulty, or advise whether this is a wise direction. I was simply attempting to answer your direct question of how you whould go about doing such a thing.

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