Grandstream Networks HT812 Administration Manual page 41

NAT Traversal
DNS Mode
DNS SRV use Registered IP
TEL URI
Use Request Routing ID in
SIP INVITE
SIP Registration
Indicates type of NAT for each account. This parameter configures whether the
NAT traversal mechanism is activated. Users could select the mechanism from
No, Keep-alive, STUN, UPnP.
Default setting is No.
Selects DNS mode to use for the client to look up server. One mode can be
chosen.

A Record: resolves IP Address of target according to domain name.

SRV: DNS SRV resource records indicate how to find services for
various protocols.

NAPTR/SRV: Naming Authority Pointer according to RFC 2915.

Use Configured IP: If selected, please fill in Primary IP, Backup IP 1
and Backup IP 2 to be used for server look up.
Default is A Record.
When the HT81x is registered using the second SRV record, making an
outbound call, it will try the second SRV (registered IP) first. By default, this
option is disabled and the DNS SRV will use first SRV instead of the
registered IP.
Indicates E.164 number in "From" header by adding "User=Phone" parameter
or using "Tel:" in SIP packets, if the HT812/HT814 has an assigned PSTN
Number.

Disabled: Use "SIP User ID" information in the Request-Line and
"From" header.

User=Phone: "User=Phone" parameter will be attached to the
Request-Line and "From" header in the SIP request to indicate the
E.164 number. If set to "Enable".

Enabled: "Tel:" will be used instead of "sip:" in the SIP request.
Please consult your carrier before changing this parameter. Default is
Disabled.
If set to Yes, device will use the configured [Request URI Routing ID] in the
SIP INVITE. This option is usually used under a SIP trunk account's
configuration. Default is No.
Controls whether the HT812/HT814 needs to send REGISTER messages to
the proxy server. Default setting is Yes.
HT812/HT814 Administration Guide
Version 1.0.9.3
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