NAME

       Net::SIP::NATHelper::Server - server for Net::SIP::NATHelper::Client

DESCRIPTION

       This module is a wrapper around Net::SIP::NATHelper::Base and will receive it's instructions from
       Net::SIP::NATHelper::Client using RPC via sockets.

CONSTRUCTOR

       new ( [ HELPER ], @FDS )
           Will create an object which listens on all file descriptors given in FDS for RPC from clients.

           If HELPER is given and a Net::SIP::NATHelper::Base object or derived it will be used, otherwise the
           helper will be created.

METHODS

       do_command ( FD )
           Called when FD is available for reading.  Calls accept on FD and reads the RPC packet from the
           resulting file descriptor, executes it and returns result back.

           Currently implemented commands are "allocate","activate" and "close" which will map to the local
           methods allocate_sockets, activate_session and close_session.

           One might redefine or add commands by changing "$self->{commands}".  The key of this hash reference
           is the command name and the value is the callback.

           Unknown commands will be ignored, e.g nothing returned.

       loop
           This will loop over all file descriptors it gets from callbacks in Net::SIP::NATHelper::Base and the
           file descriptors for the RPC sockets.

           When file descriptors gets available for reading it will execute the callbacks, e.g. forward the RTP
           data or call do_command.  In regular intervals it will call expire from Net::SIP::NATHelper::Base to
           expire the RTP sockets and sessions.

       allocate_sockets ( ... )
           Calls allocate_sockets of the local Net::SIP::NATHelper::Base object. Takes and returns the same
           arguments.

       activate_session ( ... )
           Calls activate_session of the local Net::SIP::NATHelper::Base object. Takes the same arguments and
           returns 1 if the session was newly activated, -1 if it was activated before and false if activation
           failed.  Updates callbacks into the event loop.

       close_session ( ... )
           Calls activate_session of the local Net::SIP::NATHelper::Base object. Takes the same arguments and
           returns the number of closed sessions.  Updates callbacks into the event loop.

       expire ( ... )
           Calls expire of the local Net::SIP::NATHelper::Base object. Takes the same arguments and returns the
           number of expired sessions.  Updates callbacks into the event loop if necessary.

BUGS

       The local event loop should be pluggable, so that other implementations could be used. Right now it's a
       hard coded loop using select.