I used two 1750s as the sip gateways and connected the 2 phones on the fxs ports. In the 1750, I configured the following in one 1750. is it correct ?
phone--1750----ethernet-----1750--phone.
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dial-peer voice 1 voip
destination-pattern 1.
session protocol sipv2
session target ipv4:10.1.1.1(ip of another 1750)
dial-p voice 2 pots
destination-pattern 20
port 1/0
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