Multi-class Multipath Routing Protocol for Low Power and Lossy Networks, with Energy Balanced Optimal Rate Assignment

The wireless sensor networks (WSNs) are special network which has purpose of gathering information in certain area. Multipath routing is the paramount path of addressing QoS and energy balancing concerns in low power and lossy networks (LLNs) especially in IoT technology. Most of the extant efforts bring the limited number of disjoint paths into play, and intersect the traffic among them pursuant to a compound metric or centralized optimization problem. This paper proposes a multi-class multipath routing protocol for LLNs (called M2RPL), that construct a braided multipath routing graph based on the standard RPL (IPv6 Routing Protocol for Low-Power and Lossy Networks) protocol, and an energy balanced optimal rate assignment mechanism (EBORA) that solves a local multi class optimization problem for minimum cost traffic rate assignment. Moreover the algorithm tries to maximize network lifetime by equalizing the energy dissipation rates of equi-level nodes. The simulation results expose the efficiency of the proposed framework, leading to an average 15% increase in lifetime, and improved QoS performance in terms of delay and reliability, compared to some well-known algorithms.

Optimization of p-Cycle Protection in Mixed Line Rate WDM Networks with Limited Transmission Reaches

We consider the problem of routing and rate assignment with p-cycle protection for mixed line rate (MLR) networks that are limited by transmission reaches. The problem is formulated mathematically as integer linear programming (ILP) problems under two different assumptions. First, we consider using each p-cycle to protect working lightpaths at common fixed line rate, and refers to this case as the fixed cycle rate (FCR) approach. We then perform comparative study between the FCR approach and the mixed cycle rate (MCR) approach, which is the second case and allows each p-cycle to protect working lightpaths with various rates. The objective of each ILP problem is to minimize the overall cost function, which consists of transponder operating cost, as primary costs and p-cycle operating costs, as secondary costs. Number results show that the MCR approach yields lower cost and is more efficient as the traffic increase when compared the FCR approach. In addition, we compare the use of MLR networks to the use of single line rate (SLR) networks to verify that MLR networks yield lower costs.