一個適用於網路模擬的輕量化延時方法

A lightweight approach to Time Dilation for Network Simulation

呂致伊(Leu, Chih Yi)

指導教授 ： 林永隆

國立清華大學/電機資訊學院/資訊工程學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00355

摘要

延時是一種可以同步速度較慢的模擬器與真實運行的系統的方法。
一種常見的實作方式是利用全虛擬化技術，透過修改虛擬機管理器的內部時鐘來達到延時的效果。此方法雖然準確但是佈建困難且會耗用大量系統資源。
我們提出了一種輕量化的方式，透過攔截與修改時間相關的系統函式，我們可以在不需要全虛擬化的狀況下支援延時的功能。

關鍵字

網路模擬 ； 延時

並列摘要

Time Dilation is a technique for synchronising realtime emulators and slow simulators. It slows down time flow seen by emulators for simulators to catch up. A common approach is full-vitrualisation by patching internal clock of virtual machine hypervisor to provide virtual time to virtual machines. It is accurate but time-consuming to deploy and resource-hungry because every virtual machine needs to maintain its own guest OS. We propose a lightweight approach. By intercepting and modifying several time-related functions, we can support multiple emulators without setting up virtual machines.

並列關鍵字

NS-3 ； Time Dilation ； Network Simulation

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