Various example implementations are directed to circuits, apparatuses and methods for providing Voice-over-IP (VoIP) services. According to an example embodiment, an apparatus includes a first network node configured to communicate VoIP-packets between upstream and downstream network nodes in a network and to communicate metadata with at least one of the VoIP packets downstream in the network. The apparatus also includes a second network node configured to receive the set of metadata and at least one VoIP packet, and communicate the at least one of the VoIP packet further downstream in the network. The second network node is also configured to send a response packet upstream in response to receiving the metadata. A network pathway assessment module is configured to derive, from the response packet a latency corresponding to the VoIP-packets communicated along a pathway between the first network node and the second network node.