This is using WTT SIP Trunk with UCM6204 Dual LAN Switch Mode setting:

 

VOIP Trunk Setting

– Type a name
– Host Name: provided by WTT or HKBN

Advanced Settings

– Codec Preference select “PCMU” & “PCMA” only
– Maximum Number of call line:  Trunk Channel.

Outbound Routes (Use for dial-out)

– Pattern: “_x.”
– Trunk: SIPTrunks — WTT

Inbound Routes Setting

Let say 21546428 to Extension 6428, By DID is ok!

Network Settings

Network setting “Dual”, LAN 1 = Physical LAN port, LAN 2 = Physical WAN port.
– LAN 1 (Lan Port) use for connecting local LAN Subnet
– LAN 2 (Wan Port) use for connecting WTT SIP Trunk


Network Settings > Static Routes
– Set a static route, route 10.226.30.1 through 10.232.104.46 gateway.