This paper surveys recent results in the area of virtual path layout in ATM networks. We present a model for the theoretical study of these layouts the model amounts to covering the network with simple paths, under various constraints. The constraints are the hop count (the number of paths traversed between the vertices that have to communicate), the load (the number of paths that share an edge or a vertex), and the stretch factor (the total length traversed between pairs of vertices, reduced by the distance between them). We focus on the one-to-all (or broadcast) and the all-to-all communication problems. The results are positive (design and analysis of virtual path layout schemes, including recursive constructions, greedy and dynamic programming algorithms), and negative (lower bounds and NP-hardness). The results are presented for a variety of cases, and involving various parameters in such layouts.