NeTS: Small: Collaborative Research: Configuration Management for Mobility Support in Cellular Networks

移动性支持被认为是下一代互联网的基本服务。当前的蜂窝网络是唯一一个能够在现实中成功提供广域、无处不在的移动性支持的大规模基础设施。随着智能手机设备的爆炸式增长和移动的数据流量的激增，蜂窝网络已经演变成日益异构的联网系统。因此，管理移动性变得具有挑战性，但也有回报。本项目旨在研究2G/3G/4G网络的移动性管理配置问题，以确保理想的移动性支持。研究重点是评估两个结构属性：稳定性和可达性。稳定性意味着在恒定的网络条件下没有持续的振荡回路，而可达性表示没有访问黑洞（例如，某些小区或甚至给定的移动的技术（例如，4G）无法通过设备到达）。该项目的成功不仅将识别和表征当今蜂窝网络中的错误配置，而且还将保护快速扩展的移动的信息基础设施中的数万亿美元投资。所获得的结果可能会影响即将到来的5G无线网络的设计。拟议的研究有三个关键领域的技术贡献。首先，它采取了一种新的方法来配置研究。它建模和分析问题的情况下，并提出了一个分类的不稳定性和不可达的移动配置问题，并推导出每个有问题的情况下的触发条件。 其根本问题在于它的分布式，但没有很好地协调配置决策。第二，该项目涵盖从理论到实践的活动。鉴于在理论上发现的配置错误的情况下，它进一步经验评估他们在操作移动的网络。它试图衡量它们在现实中的可能性，并量化它们对用户设备和网络基础设施的负面影响。要分析各种根本原因，包括单个参数内的策略冲突、不同类型参数之间的不一致以及设备和网络之间的不协调决策。最后，本文提出了移动的网络配置管理的新解决方案。这项研究简化了目前的方法，同时保留其完整的参数配置。为此，两个设计准则的决策规则的最小复制和没有多跳移动性决策进行了探讨，以确保移动性支持的稳定性和可达性。

Mobility support is deemed a fundamental service for the next-generation Internet. The current cellular network is the only large-scale infrastructure that successfully provides wide-area, ubiquitous mobility support in reality. With the explosive growth of smartphone devices and the surge of mobile data traffic, cellular networks have been evolving into an increasingly heterogeneous networked system. As a result, managing mobility becomes challenging yet rewarding. This project seeks to study the configuration issues on mobility management of 2G/3G/4G networks, in order to ensure desirable mobility support. The research focuses on assessing two structural properties: stability and reachability. Stability implies no persistent oscillation loops during constant network conditions, while reachability denotes no access black hole (e.g., certain cells or even a given mobile technology (e.g., 4G) cannot be reached by the device). The success of the project will not only identify and characterize misconfigurations in today's cellular networks, but also protect multi-trillion dollar investment in the fast expanding mobile information infrastructure. The obtained results may influence the design of upcoming 5G wireless networks. The proposed research has three key areas of technical contributions. First, it takes a novel approach to configuration study. It models and analyzes problematic cases and comes up with a taxonomy of instability and unreachability for the mobility configuration problems, and derives triggering conditions for each problematic instance. The fundamental problem lies in its distributed, yet not well-coordinated configuration decision-making. Second, the project covers activities from theory to practice. Given the misconfiguration instances discovered in theory, it further empirically assesses them in operational mobile networks. It seeks to measure their likelihood in reality and quantify their negative impacts on both the user device and the network infrastructure. The diversified root causes are to be analyzed, spanning policy conflicts within a single parameter, inconsistency between different types of parameters, and uncoordinated decisions between the device and the network. Last, the research proposes new solutions to configuration management in mobile networks. This research simplifies the current approach, while retaining its full configurability for parameters. To this end, two design guidelines of minimal replication of decision rules and no multi-hop mobility decision are explored in order to ensure both stability and reachability of mobility support.