[Asterisk-Users] Asterisk : No Sound Issues

[Greg Hill]

On Sat, 7 Aug 2004, niko singh wrote:

> Thanks greg , for pointing out the valuable resources for reference. I
> tried SJphone in a windows environment to connect to fwd and it worked
> fine(including (audio). Now have to do the same thing for linux(red hat
> 9 )  and hope the nat issue is resolved.

your mention of firewalls below reminded me of a certain "feature"
included with RedHat 9. The installer likes to set up a firewall (using
the ipchains tools) to help protect the machine against attacks. This
could potentially cause problems if the firewall blocks connections when
your softphones try to register with asterisk. A quick-and-easy temporary
fix is to remove the firewall rules entirely by using "iptables -F;
iptables -X" as root. The firewall rules are restored the next time you
reboot. Long term, it would definitely be a good idea to read about
firewalls with ipchains and get yours set up as you need.

> Now i would like to connect asterisk to fwd and instead of the SJ phone
> connecting to fwd directly i would wish to connect through asterisk, writing
> the extensions to transfer all dailled numbers from my SJphone to fwd. At a
> later stage make asterisk accept calls dialled to my fwd number and operate
> thm through the SJ phone

register your box to fwd (for incoming calls to your fwd number): add to
sip.conf in the [general] secion
register => fwdnum:fwdpass at fwd.pulver.com
calls to your fwd number will be routed to your context specified in the
[general] section.

To make calls to the fwd network, you'll need something like this in
sip.conf:
[fwd]
type=friend
secret=
username=
host=fwd.pulver.com
context=incoming

and then in your extensions.conf something like:
exten => _8.,1,Dial(SIP/${EXTEN:1}@fwd)

then any number that starts with an 8 will be tried at fwd. This exten
statement would need to be in the same context as your softphones in order
for them to use it.

> How can nat issues be resolved with asterisk.

typically you have to set up port forwarding on your nat device and use
externip= in sip.conf. You may also need to use canreinvite=no in some
contexts of sip.conf as well as nat=yes. Keep browsing and searching,
especially on the wiki but also on google.

Greg