SRST phone registration procedure uses the translation pattern in transformation mask how phone get registered.
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sccp local FastEthernet0/0
sccp ccm 10.4.13.20 identifier 10
sccp ccm 10.4.13.70 identifier 12
sccp ccm 172.16.10.40 identifier 30
sccp
!
sccp ccm group 1
associate ccm 10 priority 1
associate ccm 12 priority 2
associate ccm 30 priority 3
switchback method graceful
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