A customer has a z13 server. They plan to use Server Time Protocol (STP) for accessing an external time source (UTC).
Which of the following techniques can be used to get the time information in this scenario?
A . Configuration of a Network Time Protocol (NTP) client on the HMC which accesses an external NTO server.
B . Use of an External Time Reference (9037-002) in an STP mixed Coordinated Timing Network.
C . SE dial out to an external time reference.
D . Edit PR/SM to connect oscillator cards to a tlsdate server.
Answer: B
Explanation:
Network Time Protocol (NTP) client support
The external time source (ETS) function of STP can provide accurate time relative to an external time standard for data processing applications. The ETS function is only available when an STP-only CTN is configured. The external time source can be configured by dialing out from the HMC to an available time service such as Automated Computer Time Service (ACTS). Dialing out provides time accuracy for the z Systems timing network only. This function has been generally available since January 31, 2007 when STP became generally available.
An alternative method to obtain accurate time is from an NTP server. Simple Network Time Protocol (SNTP) client support is added to the Server Time Protocol code to interface with NTP servers. NTP client support can provide the same time across heterogeneous platforms in an enterprise with a time accuracy of 100 milliseconds.
References: https://www-03.ibm.com/systems/z/advantages/pso/stp/ntp.html