Inbound Settings - Snom ONE IP Technical Manual

the redirection destination can easily be abused to route calls through
expensive routes.
— Always, except for busy response: Even if the remote party is busy, the
system will try alternate routes.
If you are using failover, you have the option to specify a request timeout value
for the trunk. By default, this is 32 seconds (the SIP default request timeout).
However, in many cases, it makes sense to specify a shorter value. After the
request timeout, the system will internally generate a "408 Request Timeout"
response code and process it according to the failover rules.
32. Is Secure: This setting is used to indicate that outbound calls on the trunk can
be treated as secure calls. For example, when the trunk goes to a local PSTN
gateway, you might decide to treat this call as a secure call. Incoming calls with
the SIPS scheme will ask the snom ONE system to ensure that the call be kept
secure end-to-end.
33. ICID (RFC 3455): This setting is used in the IMS environment and is sent
in the P-Charging-Vector
essentially a token that identifies the trunk. If your provider uses this header, it
should be placed into this field.

Inbound Settings

34. Explicitly list addresses for inbound traffic: This setting allows you to explic-
itly state trusted inbound proxy addresses and enables you to identify the origin
of the request. It is ideal for VPN environments or when routing calls between
offices, as it allows you to create a single trunk and specify the IP addresses of
the other locations. The addresses can be either IP addresses (with an optional
port number behind) or a DNS A or AAAA address.
Chapter 4: Trunks
header of the SIP packets on the trunk. It is
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