Yealink SIP-T54S Administrator's Manual page 258

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
Enter the desired value in Label, Display Name, Register Name, User Name, Password and
4.
SIP Server1/2 field respectively.
If you use outbound proxy servers, do the following:
5.
Select Enabled from the pull-down list of Enable Outbound Proxy Server.
1)
Enter the desired IP address or domain name in the Outbound Proxy Server 1/2
2)
field and the desired port of the outbound proxy server 1/2 in the Port field
respectively.
Click Confirm to accept the change.
6.
To configure the interval for re-register when registration fails via web user interface:
Click Account->Advanced.
1.
Select the desired account from the pull-down list of Account.
2.
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