在這篇論文裡面，我們考慮全域繞線下的最小層分配。我們將一個初步給定的一層結果中的溢滿總量和最大溢滿當做給定的壅塞條件，並且希望在這種環境下找到接點最小化的層分配。為了解決這個問題，我們提出一個演算法先產生一個電路順序然後依序使用動態規劃將每個電路問題解決
　我們採用ISPD 2007全域繞線比賽的測試資料來測試我們的演算法，而實驗結果顯示我們的方法對於目前最先進的繞線器MaizeRouter平均可以達到7.77%，BoxRouter達到16.69%，以及FGR達到2.11%的接點最小化之層分配改善。

Abstract
In this thesis, we study the problem of layer assignment for via minimization that arises during multi-layer global routing. In this problem, we take total overflow and maximum flow as the congestion constraints from an initial one-layer routing solution and we want to find a layer assignment result for each net such that the via cost is as small as possible while the given congestion constraints are satisfied. This layer assignment problem is different from the well-known constrained via minimization problem that is handled after detailed routing. To solve this problem, we propose a sequential algorithm which first generates a net order, and then according to the order, performs layer assignment one net at a time by using dynamic programming
We use the benchmarks released from the ISPD’07 global routing contest to test our algorithm, and the experimental results show that our algorithm can get averagely 7.77%, 16.69%, and 2.11% improvement rates on the via cost as compared to three state-of-the-art multi-layer global routers, MaizeRouter, BoxRouter and FGR, which were known to the top three winners of the multi-layer category at the ISPD’07 global routing contest.

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