Most location problems on networks consider discretenodal demand. However, for many problems, demands are betterrepresentedby continuous functions along the edges, in addition to nodaldemands. Several papers consider the optimal location problemof one or more facilities when demands are continuously distributedalong the network, and the objective function dealt with is themedian one. Nevertheless, in location of public services itis desirable to use an equity criterion. One of the latter is varianceofdistance distribution which has been studied only for discrete nodaldemands. In this paper the variance problem has been generalizedto the case where one allows the demand to arisediscretely on the nodes as well as continuously along the edges. Properties and behaviour of the objective function arestudied. Likewise we present an exact algorithm forsolving this problem in a network, which reduces the complexityof the exhaustive procedure.