Phones supporting DNS-SRV and/or DNS NAPTR

Using DNS-SRV/NAPTR the phone will perform automatic failover in case of service disruptions. Because of that, it is highly recommended to use this functionality. Most recently purchased phones should support this feature.


How to enable DNS-SRV or NAPTR varies from phone to phone, but most commonly this is either found in the setting for the "Transport protocol" or a separate setting like "DNS Lookup mode". Refer to the phones' manual for more information.


Parameter
Value
Note
Server
sip.kwebbl.net
Or whitelabel equivalent.
Port
0 or empty
Depending on the type phone, you should either choose 0 or empty.
Registration time
60 seconds
The lower the registration time, the quicker the failover. The minimum allowed registration time by Kwebbl is 60 seconds.
Outbound proxy, registration server
empty
Using a specific outbound proxy or registration server could break the failover functionality.


If your phone support NAPTR, it will automatically select the transport protocol. By default TLS is preferred, followed by UDP and finally TCP. If you would like to influence which protocol is used, you can use any of the following domains as server:


Server
TLS
UDP
TCP
sip.kwebbl.net
Y (1st preference)
Y (2nd preference)
Y (3rd preference)
notls.sip.kwebbl.net
N
Y (1st preference)
Y (2nd preference)
noudp.sip.kwebbl.net
Y (1st preference)
N
Y (2nd preference)
notcp.sip.kwebbl.net
Y (1st preference)
Y (2nd preference)
N
tlsonly.sip.kwebbl.net
Y
N
N
udponly.sip.kwebbl.net
N
Y
N
tcponly.sip.kwebbl.net
N
N
Y


Phones not supporting DNS-SRV, but supporting Primary / Secondary servers.

If your phone does not support DNS-SRV, it is recommended to configure it using Primary / Secondary servers. Although less extensive than DNS-SRV, it does offer some features to perform automatic failovers in case of service disruptions.


Parameter
Value
Note
Primary Server
primary.sip.kwebbl.net
Or whitelabel equivalent. Sometimes called main server or server 1.
Secondary Server
secondary.sip.kwebbl.net
Or whitelabel equivalent. Sometimes called backup server or alternate server.
Port
5060

Transport protocol
UDP
Using TCP or TLS for this configuration mode is not recommended.
Registration time
60 seconds
The lower the registration time, the quicker the failover. The minimum allowed registration time by Kwebbl is 60 seconds.
Outbound proxy, registration server
empty
Using a specific outbound proxy or registration server could break the failover functionality.


Legacy Phones not supporting DNS-SRV or Primary / Secondary servers.

If your phone does not support DNS-SRV or Primary / Secondary servers. Although less extensive than DNS-SRV, you will not have any failover in case of service disruptions.


Parameter
Value
Note
Server
sip.kwebbl.net
Or whitelabel equivalent.
Port
5060

Transport protocol
UDP
Using TCP or TLS for this configuration mode is not recommended.
Registration time
300 seconds


The outbound proxy could also be set to sip.kwebbl.net, especially some older or less-common phones may require this to function properly.