多技術/多設備/多服務電信用戶幹線網路投資規劃模式與方法之研究

Abstract

在各國電信公司爭相邁入整體服務數位網路（簡稱ISDN）的趨勢中，如何適時且經濟地引進適量的新技術與新設備於電信網路，以滿足顧客各式各樣的服務需求，進而達到增裕盈餘的目標，一直是各國電信公司營運上最重要的考量。 本論文針對電信網路投資比重最大，規劃最複雜也最具挑戰性的用戶幹線網路部份加以探討，並提出一套用戶幹線網路投資規劃程序與方法，來求解投資多傳輸技術/多傳輸設備/多服務之電信用戶幹線網路時，規劃上所面臨的主要問題，即：設置時間、設置地點、設置種類及設置數量之決定，以使規劃年限內總投資最經濟。 首先，根據目標年間各年各服務區內之各式服務需求數（皆以DS0當量需求數來表示），及各類傳輸線與傳輸設備的固定與變動成本（皆以年金現值來表示）等參數值下，將網路拓撲設計問題化成〝最小成本網路流量問題〞，以求解各年用戶幹線網路內，各傳輸線與各傳輸設備之最適設備供應數量（即各年的經濟網路架構與設備供應狀況）。 接下來，再依目前網路設備供應狀況與前面所得的各年經濟網路設備供應狀況，將網路設備擴充規劃問題，視為〝需求確定下之批量採購問題〞，以求解出該用戶幹線網路內，各傳輸線與各傳輸設備在目標年間之最適擴充時程、規格及批量數（即容量擴充計畫）。 最後，本論文依據所提的規劃模式與方法，發展求解程式來進行一連串的實証分析。用此來証明本論文所提之規劃模式與方法，皆屬可行，同時也進一步指出未來研究方向的建議。

The Integrated Services Digital Network (ISDN) has become a trend for the telecoms all over the world. From an operational point of view, however, the most critical considerations for these companies are how to bring the new technologies and new equipment economically and timely so that they can satisfy the demand of various services from customers and increase earnings at the same time. Local Access Network (LAN) is the most complicated part of the telecommunication network. It usually incurs the highest proportion of the investment for the network deployment. The main problems that planning the investment for LAN will face include timing (when), location (where), typing (what equipment), sizing (how many quantities). This paper proposes a investment planning methodology to make the overall investment most economical. First, by incorporating the objective years, demands of different services in each distribution point (DP) every year, and cost parameters of different transmission media and equipments. The investment planning problem can be treated and solved as a minimum cost network flow problem with fixed-cost nodes, which yields the most economical conditions of network supply for individual years. And then, based on the results of the first stage as well as the current condition of network supply, the capacity planning is treated as a batch purchase problem under given demands. The time schedule of the most economical network investment plan for the objective years can then be obtained.