Secure Peer-to-Peer Overlay Networks

CCR-0311795标题：安全对等覆盖网络PI：Baruch Awerbuch和Christian Scheideler，约翰霍普金斯大学摘要对等（P2P）系统最近由于各种原因变得非常流行。例如，点对点系统不需要中央服务器，这意味着个人可以在没有额外的高性能硬件费用或投资的情况下进行合作。此外，对等系统允许使用否则在各个计算机上闲置的计算和存储资源。此外，P2P系统的去中心化和分布式特性使其对意外故障具有鲁棒性。不幸的是，许多现有和提出的P2P系统的体系结构都假设节点可以被信任不会有恶意行为。虽然在中央认证机构的帮助下这是可能实现的，但在许多情况下，限制P2P系统的成员资格是不可取的。因此，系统必须能够抵御各种安全攻击。许多现有的系统是相当脆弱的安全对非常温和的攻击，我们称之为不幸的输入攻击。不需要做任何恶意的事情来执行重大的拒绝服务。即使所有处理器都严格遵守协议，系统也可能会遇到连接性极差（因此性能极差）或某些站点内存溢出的情况。此外，如果用户在不适当的时候离开网络，他们可能会永久删除数据或断开某些网站。虽然这些坏运气事件可能很少发生，但攻击者可以显著减少此类事件所需的时间，而不会做任何非法的事情，例如更改协议或嗅探其他对等体之间的通信。这些异常利用现有方法中的“小理论故障”，但它们可以作为主要DOS攻击的平台。这项工作的目标是为对等系统开发一个良好的理论基础，以便在现有系统中解决这些问题。

CCR-0311795Title: Secure Peer-to-Peer Overlay NetworksPIs: Baruch Awerbuch and Christian Scheideler, Johns Hopkins UniversityABSTRACTPeer-to-peer (P2P) systems have recently become extremely popular for a variety of reasons. For example, the fact that peer-to-peer systems do not need a central server means that individuals can cooperate without fees or an investment in additional high-performance hardware. Also, peer-to-peer systems enable the use of computations and storage resources that otherwise sit idle on individual computers. Furthermore, the decentralized and distributed nature of peer-to-peer systems makes them robust against accidental faults.Unfortunately, the architecture of many current and proposed P2P systems assumes that the nodes can be trusted not to behave maliciously. While this may be possible to achieve with the help of a central certification authority, in many situations it is not desirable to constrain the membership of a P2P system. Consequently, the system must be able to withstand a variety of security attacks. Many of the existing systems are quite vulnerable security against very mild attacks that we call unlucky-input attacks. There is no need to do anything malicious to execute a major denial of service. Even if all processors follow the protocol to the letter, it is possible for the system to run into a situation with extremely poor connectivity (and therefore performance) or a memory overflow at some sites. Furthermore, if users leave the network at inopportune times, they may permanently remove data or disconnect some sites. Although these bad luck events may rarely happen, an adversary can significantly reduce the time required for such events without doing anything illegal such as altering the protocol or sniffing at communication between other peers. These anomalies exploit "minor theoretical glitches" in the existing approaches, and but they could serve as a platform for major DOS attacks.The goal of this work is to develop a sound theoretical foundation for peer-to-peer systems that will allow fixing these problems in existing systems.