Recently, multipaths solutions have been proposed to improve the quality-of-service (QoS) in communication networks (CN). Peng and Shen algorithm (PSA) was proposed to generate lambdaDP/DC - the maximum edge-disjoint-path-set with minimal cost subject to a delay constraint, for lambdales2. This paper introduces a different and equally important problem, lambdaDP/DR, to obtain the maximal edge-disjoint-path-set with maximum reliability subject to a given delay constraint, for lambdales1. lambdaDP/DR is applicable to time critical applications that require non-compromised time delay while demanding maximum system reliability. In this paper we show how lambdaDP/DR is different from lambdaDP/DC, and propose an approximate algorithm similar to the Lagrange-relaxation based PSA to solve the problem. Our simulations on three randomly generated CNs show that our polynomial time algorithm produced lambdaDP/DR with comparable optimality to that obtained using the NP-hard brute-force approach.