Packet loss in wired communication networks is almost entirely caused by buffer overflow in intermediate network nodes. Although the packet loss ratio at a (bottleneck) buffer is an important performance measure, it is often an insufficient measure to accurately assess the impact of loss on overall network performance. This contribution therefore focuses on various flow level packet loss characteristics of a network node. The network node is modelled as a quasi-birth-death finite-capacity queueing system such that various levels of arrival correlation can be captured while maintaining analytical tractability. Some numerical examples illustrate the approach considered.