Separable convex optimization problems with linear ascending inequality and equality constraints are addressed in this paper. An algorithm that explicitly characterizes the optimum point in a finite number of steps is described. The optimum value is shown to be monotone with respect to a partial order on the constraint parameters. Moreover, the optimum value is convex with respect to these parameters. This work generalizes the existing algorithms of Morton, von Randow, and Ringwald [Math. Programming, 32 (1985), pp. 238–241] and Viswanath and Anantharam [IEEE Trans. Inform. Theory, 48 (2002), pp. 1295–1318] to a wider class of separable convex objective functions. Computational experiments that compare the proposed algorithm with a standard convex optimization tool are also provided. Key words. ascending constraints, convex optimization, linear constraints, separable problem AMS subject classifications. 90C25, 52A41 DOI. 10.1137/07069729X