1. A method comprising: establishing a control connection between a two-way active measurement protocol (TWAMP) control client on a first network device in a network and a TWAMP server on a second network device in the network; negotiating, by the TWAMP control client, a data session for a given service supported at the TWAMP server, the negotiation including selecting one or more service key performance indicators (KPIs) to be measured for the given service; establishing, by the TWAMP control client, the data session for the given service with the TWAMP server; sending, by a TWAMP session initiator on a third network device in the network, one or more TWAMP test packets to the TWAMP server over the data session for the given service; and sending, by the TWAMP server in response to the one or more TWAMP test packets, service data measurements for the selected service KPIs for the given service over the data session to the TWAMP session initiator.