use Authen::Radius;

my $rad = new Authen::Radius('Host' => '1.2.3.4:1700', 'Secret' => 'secret');
Authen::Radius->load_dictionary();

foreach (...)
{
    my $ret;
    $rad->clear_attributes();
    $rad->add_attributes({'Name'=>'RBN-Context_Name', 'Value'=>'local'});
    $rad->add_attributes({'Name'=>'Acct-Session-Id', 'Value'=>$_->{'SESSION_ID'}});
    $rad->add_attributes({'Name'=>'Framed-IP-Address', 'Value'=>$_->{'IP'}});
    $rad->send_packet(DISCONNECT_REQUEST) and $ret = $rad->recv_packet();
    if (defined($ret))
    {
        print "$ret\n";
    }
    else
    {
        print "*ошибка " . $rad->get_error();
    }
}