[plug] VOIP setup for Linux network

[Chris Caston]

Hello,

I'm looking at going through a third party provider for a POTS
accessible VOIP based business line.

The company is called Platinum Calling
(http://www.platinumcalling.com.au)

We are still yet to establish how to technically setup the connection
but I am considering implementing a SIP proxy to allow machines inside
the NAT based local address range to send and receive calls.


I do have adsl and a staic IP but they suggested I may need *two* IP's.

So can you usually use SIP proxies with an upstream provider?

Examples:

(http://sourceforge.net/projects/siproxd/)

(http://sourceforge.net/projects/sarp/)

(http://sourceforge.net/projects/osipproxy/)


I could use linphone, kphone or gnome meeting with a headset and the
speakers turned up for the ringtone but I would also like to use a SIP
phone but the only IP phones I have a supplier for at the moment are the
Cisco IP Phones and the ATA186/188  to make standard touch tone phone
VOIP capable.

I believe the Cisco phones use Slinky but can they also use SIP?

If so do I need to use a Cisco call manager or can I get them talking to
the SIP proxy. 

According to the Cisco IP phone faq
(http://www.cisco.com/en/US/products/hw/phones/ps379/products_qanda_item09186a00800a6763.shtml)
they appear to work like this:


A. The registration of a Cisco IP Phone with Cisco CallManager is a four
step process.

 
The phone will request an IP address from the DHCP service.
 
The DHCP response will return the address of the TFTP server in one of
the following forms: 
Static IP address
 
Option 150 (single IP address)
 
Option 66 (first IP address or DNS name)
 
Lookup CiscoCM1.your.domain
 
Once the phone has the TFTP address, the phone requests its
configuration information from the TFTP server. In Cisco CallManager
3.0, this configuration information is in the form of a .cnf file. In
release 3.1 the configuration file is an .xml file. The configuration
information will contain a prioritized list of up to three Cisco
CallManager servers, the device pool the phone belongs to, and
information about the phone load version if it is release 3.1.
 
The phone will establish communication with the highest Cisco
CallManager in the prioritized list and send a registration request. If
the phone requests a .cnf file rather than a .xml file, it will also
send a version request and check the current phone load version. If the
phone needs a new phone load, it will abort the registration process and
download the current phone load form the TFTP server. Once the phone has
downloaded the new firmware, it will continue its registration with
Cisco CallManager. Refer to Troubleshooting Cisco IP Phone (7910, 7940,
7960, 12SP, and VIP30) Registration Problems with Cisco CallManager 3.x
to help resolve issues with registration of IP phones.

Any and all insights, ideas and experiences are greatly appreciated.

regards,

Chris
-- 
Linux is ready for the desktop like a Boeing F-22 is ready for the
run-way.