Enabling Differentiated Services Using Generalized Power Control Model in Optical Networks

This paper considers a generalized framework to study OSNR optimization-based end-to-end link level power control problems in optical networks. We combine favorable features of game-theoretical approach and central cost approach to allow different service groups within the network. We develop solutions concepts for both cases of empty and nonempty feasible sets. In addition, we derive and prove the convergence of a distributed iterative algorithm for different classes of users. In the end, we use numerical examples to illustrate the novel framework.

💡 Research Summary

The paper addresses the problem of allocating optical transmit powers in reconfigurable wavelength‑division‑multiplexed (WDM) networks so that each channel’s optical signal‑to‑noise ratio (OSNR) meets its service requirements while minimizing overall power consumption. Two classical approaches have been used in prior work: (1) a “central‑cost” method that minimizes total power subject to OSNR constraints, and (2) a non‑cooperative game‑theoretic method in which each user independently minimizes a cost function that trades off power expenditure against OSNR improvement. The central‑cost formulation yields a simple linear program with a closed‑form solution but does not directly maximize OSNR; the game‑theoretic formulation directly optimizes OSNR and leads to a Nash equilibrium, yet it can cause over‑allocation of power because users pay a price for each unit of power.

To combine the advantages of both, the authors propose a generalized power‑control model that distinguishes two classes of users. “Game users” (set N₁) are willing to pay a price and thus participate in the game‑theoretic optimization; “target users” (set N₂) are required only to meet a minimum OSNR level γᵢ set by the network. The OSNR of channel i is expressed as

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