[Serusers] newby help

[Jay Binks]

howdy all..
 Im in the process of trying to setup SER on a co-located server
it appears to be working, I can make calls between registered UA's  
however the RTP Stream seems
like its not working..
I am 95% sure this is because each use is within their own NAT'd network 
(Home DSL connections)
I have put Nat Helper on... but its not helping a whole not...
also have tried using STUN but this dosnt help a bunch either

have read somewhere that we may need RTP Proxy for this to work...
can someone expand on this alittle more ..


Below is my ser.cfg file this may help you suggest what to do
******************************************************************************** 

******************************************************************************** 


#
# $Id: ser.cfg,v 1.21.4.1 2003/11/10 15:35:15 andrei Exp $
#
# simple quick-start config script
#

# ----------- global configuration parameters ------------------------

#debug=3         # debug level (cmd line: -dddddddddd)
#fork=yes
#log_stderror=no        # (cmd line: -E)

/* Uncomment these lines to enter debugging mode
debug=7
fork=no
log_stderror=yes
*/

check_via=no    # (cmd. line: -v)
dns=no           # (cmd. line: -r)
rev_dns=no      # (cmd. line: -R)
#port=5060
#children=4
fifo="/tmp/ser_fifo"

# ------------------ module loading ----------------------------------

# Uncomment this if you want to use SQL database
loadmodule "/usr/lib/ser/modules/mysql.so"

loadmodule "/usr/lib/ser/modules/uri.so"
loadmodule "/usr/lib/ser/modules/acc.so"
loadmodule "/usr/lib/ser/modules/sl.so"
loadmodule "/usr/lib/ser/modules/tm.so"
loadmodule "/usr/lib/ser/modules/rr.so"
loadmodule "/usr/lib/ser/modules/maxfwd.so"
loadmodule "/usr/lib/ser/modules/usrloc.so"
loadmodule "/usr/lib/ser/modules/registrar.so"
loadmodule "/usr/lib/ser/modules/nathelper.so"

# Uncomment this if you want digest authentication
# mysql.so must be loaded !
loadmodule "/usr/lib/ser/modules/auth.so"
loadmodule "/usr/lib/ser/modules/auth_db.so"

# ----------------- setting module-specific parameters ---------------

#-- Nat Helper
 modparam("registrar", "nat_flag", 6)
 modparam("nathelper", "natping_interval", 30) # Ping interval 30 s
 modparam("nathelper", "ping_nated_only", 1)   # Ping only clients 
behind NAT


#-- Accounting Paramaters
 modparam("acc", "log_level", 1)

 # that is the flag for which we will account . don't forget to
 # set the same one :-)
 modparam("acc", "log_flag", 1 )

# -- usrloc params --

#modparam("usrloc", "db_mode",   0)

# Uncomment this if you want to use SQL database
# for persistent storage and comment the previous line
modparam("usrloc", "db_mode", 2)

# -- auth params --
# Uncomment if you are using auth module
#
modparam("auth_db", "calculate_ha1", yes)
#
# If you set "calculate_ha1" parameter to yes (which true in this config),
# uncomment also the following parameter)
#
modparam("auth_db", "password_column", "password")

# -- rr params --
# add value to ;lr param to make some broken UAs happy
modparam("rr", "enable_full_lr", 1)

# -------------------------  request routing logic -------------------

# main routing logic

route{

       # initial sanity checks -- messages with
       # max_forwards==0, or excessively long requests
       if (!mf_process_maxfwd_header("10")) {
               sl_send_reply("483","Too Many Hops");
               break;
       };
       if ( msg:len > max_len ) {
               sl_send_reply("513", "Message too big");
               break;
       };

# !! Nathelper
       # Special handling for NATed clients; first, NAT test is
       # executed: it looks for via!=received and RFC1918 addresses
       # in Contact (may fail if line-folding is used); also,
       # the received test should, if completed, should check all
       # vias for rpesence of received
       if (nat_uac_test("3")) {
               # Allow RR-ed requests, as these may indicate that
               # a NAT-enabled proxy takes care of it; unless it is
               # a REGISTER

#               if (method == "REGISTER" || ! search("^Record-Route:")) {
              if (method == "REGISTER" ){
                  log("LOG: Someone trying to register from private IP, 
rewriting\n");

                   # This will work only for user agents that support 
symmetric
                   # communication. We tested quite many of them and 
majority is
                   # smart enough to be symmetric. In some phones it 
takes a configuration
                   # option. With Cisco 7960, it is called 
NAT_Enable=Yes, with kphone it is
                   # called "symmetric media" and "symmetric signalling".

                   fix_nated_contact(); # Rewrite contact with source IP 
of signalling
                   if (method == "INVITE") {
                       fix_nated_sdp("1"); # Add direction=active to SDP
                   };

                   force_rport(); # Add rport parameter to topmost Via
                   setflag(6);    # Mark as NATed
               };
       };


       # we record-route all messages -- to make sure that
       # subsequent messages will go through our proxy; that's
       # particularly good if upstream and downstream entities
       # use different transport protocol
       record_route();
       # loose-route processing
       if (loose_route()) {
               t_relay();
               break;
       };

       # if the request is for other domain use UsrLoc
       # (in case, it does not work, use the following command
       # with proper names and addresses in it)
       if (uri==myself) {

               if (method=="REGISTER") {

# Uncomment this if you want to use digest authentication
                       if (!www_authorize("sip.em-tech.com.au", 
"subscriber")) {
                               www_challenge("sip.em-tech.com.au", "0");
                               break;
                       };

                       save("location");
                       break;
               };

               # native SIP destinations are handled using our USRLOC DB
               if (!lookup("location")) {
                       sl_send_reply("404", "Not Found");
                       break;
               };
       };
       # forward to current uri now; use stateful forwarding; that
       # works reliably even if we forward from TCP to UDP
       if (!t_relay()) {
               sl_reply_error();
       };

}


# !! Nathelper
onreply_route[1] {
   # NATed transaction ?
   if (isflagset(6) && status =~ "(183)|2[0-9][0-9]") {
       fix_nated_contact();
       force_rtp_proxy();
   # otherwise, is it a transaction behind a NAT and we did not
   # know at time of request processing ? (RFC1918 contacts)
   } else if (nat_uac_test("1")) {
       fix_nated_contact();
   };
}