To accommodate an increasing amount of traffic efficiently, elastic optical networks (EON) that can use optical spectrum resources flexibly have been studied. We implement multi-path routing in case we cannot allocate the spectrum with single-path routing. However, multi-path routing requires more guard bands to avoid interference between two adjacent optical paths when compared with single-path routing in EON. A multi-path routing algorithm with traffic grooming technology has been proposed. The researchers assumed that a uniform modulation level was adopted, and so they did not consider the impact of path length on the resources needed. In this paper, we propose a multi-path routing method with traffic grooming considering path lengths. Our proposed method establishes an optical multi-path considering path length, fiber utilization, and the use of traffic grooming. Simulations show we can decrease the call-blocking probability by approximately 24.8% in NSFNET. We also demonstrate the effectiveness of traffic grooming and the improvement in the utilization ratio of optical spectrum resources.

This paper proposes the radio ATM entrance network with radio links connecting between access points and wired backbone ATM networks for wireless ATM access. In order to reduce the interference power among the radio entrance links, the Power and Modulation Level Controlled Radio method is newly proposed, the method controls not only modulation level but also the transmission power according to the ATM cell traffic intensity. Theoretical analysis shows that the proposed method can increase the carrier to noise plus interference power ratio and can reduce the average cell loss rate compared with the conventional Modulation Level Controlled Radio method in case that there is the interference power among the radio ATM entrance links.