cpace, those commands are still correct for a 1720. This is copied from my 1720 ....
collossus#conf t
Enter configuration commands, one per line. End with CNTL/Z.
collossus(config)#ntp ?
access-group Control NTP access
authenticate Authenticate time sources
authentication-key Authentication key for trusted time sources
broadcastdelay Estimated round-trip delay
clock-period Length of hardware clock tick
master Act as NTP master clock
max-associations Set maximum number of associations
peer Configure NTP peer
server Configure NTP server
source Configure interface for source address
trusted-key Key numbers for trusted time sources
collossus(config)#ntp
Chris.
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Chris Andrew, CCNA
chrisac@gmx.co.uk
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