Definition

SIP Plug & Play (PnP) provides a proprietary method to enable "Auto Provisioning" on Snom phones. By default, the phones send SIP SUBSCRIBE messages to a multicast address. Any SIP server understanding that message may reply with a SIP NOTIFY message containing the Auto Provisioning Server URL (setting_server URL) where the phones can request their configuration file from.

SIP flow

On boot-up, Snom phones send a SIP SUBSCRIBE message to a multicast address:

Sent to udp:224.0.1.75:5060 at 24/12/2001 00:00:19:248 (448 bytes):

SUBSCRIBE sip:MAC%3a00135E874B49@intern.snom.de SIP/2.0
Via: SIP/2.0/UDP 192.168.10.67:5060;rport
From: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=658512961
To: <sip:MAC%3a00135E874B49@intern.snom.de>
Call-ID: 1930770594@192.168.10.67
CSeq: 1 SUBSCRIBE
Event: ua-profile;profile-type="device";vendor="OEM";model="OEM";version="7.1.19"
Expires: 0
Accept: application/url
Contact: <sip:192.168.10.67:5060>
Content-Length: 0


If any SIP application within one hop range understands this message a confirmation is sent:

Received from udp:192.168.100.10:5060 at 24/12/2001 00:00:19:287 (480 bytes):

SIP/2.0 200 OK
Via: SIP/2.0/UDP 192.168.10.67:5060;rport=5060
Record-Route: <sip:127.0.0.1;lr;transport=tcp;route-id=fb4fb92b7775c2a7>
Record-Route: <sip:192.168.100.10;lr;transport=UDP;route-id=fb4fb92b7775c2a7>
Contact: <sip:192.168.100.10;transport=TCP;handler=dum>
To: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=91955270
From: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=658512961
Call-ID: 1930770594@192.168.10.67
CSeq: 1 SUBSCRIBE
Expires: 0 
Content-Length: 0


Dollowed by a SIP NOTIFY message containing the Auto Provisioning URL "http://192.168.100.10/sipphone/sipphoneconfig.xml?mac={mac}":

Received from udp:192.168.100.10:5060 at 24/12/2001 00:00:19:293 (868 bytes):

NOTIFY sip:192.168.10.67:5060 SIP/2.0
Via: SIP/2.0/UDP 192.168.100.10:5060;branch=z9hG4bK-d8754z-c3ea5f0e74462613-1---d8754z-;rport
Via: SIP/2.0/TCP 127.0.0.1:5060;branch=z9hG4bK-d8754z-7ca96c30144f3e04-1---d8754z-;rport=40916
Max-Forwards: 20
Record-Route: <sip:192.168.100.10;lr;route-id=e3470eb400e9c0a4>
Record-Route: <sip:127.0.0.1;lr;transport=TCP;route-id=e3470eb400e9c0a4>
Contact: <sip:192.168.100.10;transport=TCP;handler=dum>
To: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=658512961
From: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=91955270
Call-ID: 1930770594@192.168.10.67
CSeq: 3 NOTIFY
Content-Type: application/url
Subscription-State: terminated;reason=timeout
Event: ua-profile;profile-type="device";vendor="OEM";model="OEM";version="7.1.19"
Content-Length: 59

http://192.168.100.10/sipphone/sipphoneconfig.xml?mac={mac}


The phone accepts this message and confirms:

Sent to udp:192.168.100.10:5060 at 24/12/2001 00:00:19:315 (542 bytes):

SIP/2.0 200 Ok
Via: SIP/2.0/UDP 192.168.100.10:5060;branch=z9hG4bK-d8754z-c3ea5f0e74462613-1---d8754z-;rport=5060
Via: SIP/2.0/TCP 127.0.0.1:5060;branch=z9hG4bK-d8754z-7ca96c30144f3e04-1---d8754z-;rport=40916
Record-Route: <sip:192.168.100.10;lr;route-id=e3470eb400e9c0a4>
Record-Route: <sip:127.0.0.1;lr;transport=TCP;route-id=e3470eb400e9c0a4>
From: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=91955270
To: <sip:MAC%3a00135E874B49@intern.snom.de>;tag=658512961
Call-ID: 1930770594@192.168.10.67
CSeq: 3 NOTIFY
Content-Length: 0

Settings

If PnP provisioning has been used, the phone will store the received URL under setting pnp_server.

PnP provisioning will not automatically populate the setting_server. If you wish to deactivate the Snom Redirection Service you can either edit parameter setting_server from your provisioning file to direct to your server or simply remove value "redirection:stop" from parameter provisioning_order.