Zhenkai Zhu

Let's ChronoSync: Decentralized dataset state synchronization in Named Data Networking

In supporting many distributed applications, such as group text messaging, file sharing, and joint editing, a basic requirement is the efficient and robust synchronization of knowledge about the dataset such as text messages, changes to the shared folder, or document edits. We propose ChronoSync protocol, which exploits the features of the Named Data Networking architecture to efficiently synchronize the state of a dataset among a distributed group of users. Using appropriate naming rules, ChronoSync summarizes the state of a dataset in a condensed cryptographic digest form and exchange it among the distributed parties. Differences of the dataset can be inferred from the digests and disseminated efficiently to all parties. With the complete and up-to-date knowledge of the dataset changes, applications can decide whether or when to fetch which pieces of the data. We implemented ChronoSync as a C++ library and developed two distributed application prototypes based on it. We show through simulations that ChronoSync is effective and efficient in synchronization dataset state, and is robust against packet losses and network partitions.

ACT: audio conference tool over named data networking

In this paper we present the design of an audio conference tool, which is one of our efforts to explore application de- signs on top of Named Data Networking. Instead of rely- ing on centralized services as current implementations do, ACT takes a named data approach to discover ongoing conferences as well as speakers in each conference, and to fetch voice data from individual speakers. The resulting design is completely distributed and robust against component failures. We discuss design alternatives and tradeoffs, scalability and security considerations, as well as remaining issues for future work.

Support mobility in the global internet

Todays technology trend indicates that billions of hand-held gadgets as well as other types of mobile devices will be coming online in the next few years. While the existing Internet mobility standards, namely Mobile IP, is waiting for a wide adoption, cellphone networks are providing the ubiquitous mobility services on a global scale as of today. They have also promoted IP core network architecture and adopted Proxy Mobile IPv6, an extension to Mobile IP, for their mobility service. There is an open question regarding whether the Internet would, or would not, require significant architectural changes to provide universal mobility support at a scale that is likely to go far beyond the scale and scope of todays cellular telephone services. In this paper, we examine the fundamental di erences between the mobility service models provided by Internet and cellphone systems. We argue that decoupling network access control from mobility support can provide an architecturally promising direction for scalable and decentralized mobile communications, and that designing mobility support outside the global routing system can o er an overall best tradeo as measured by flexibility, manageability, and scalability of the resulting systems.

A new approach to securing audio conference tools

Instead of securing the communication channel between sources and destinations as in todays Internet, Named Data Networking (NDN), a recently proposed Internet architecture, is designed to secure data directly. To further understand the design space of securing applications through securing data, we performed a case study of designing the security mechanisms for the Audio Conference Tool (ACT). Utilizing NDNs built-in primitive of signed data packets, we applied basic cryptographic schemes in a straightforward manner to effectively secure conferencing control information as well as voice data.

Supporting mobility for internet cars

In the last few years we have witnessed an increasing number of cars being connected to the Internet. All indicators suggest that this trend will continue, and vehicles will soon become first class citizens on the Internet. Vehicle networking opens the door to a vast new class of applications ranging from car monitoring and diagnosis to passenger assistance, communication, and entertainment. In this article we present a comprehensive survey of the existing mobility support solutions, and discuss various design trade-offs and remaining issues in view of vehicle networking. We hope that these discussions can provide useful inputs to car manufacturers in their design considerations for bringing all cars online.

The Story of ChronoShare, or How NDN Brought Distributed Secure File Sharing Back

Information sharing among a group of friends or colleagues in real life is usually a distributed process: we tell each other interesting or important news without any mandatory assistance or approval from a third party. Surprisingly, this is not what happens when sharing files among a group of friends over the Internet. While the goal of file sharing is to disseminate files among multiple parties, due to the constraints imposed by IPs point-to-point communication model, most of todays file sharing applications, such as Drop box, Google Drive, etc., resort to a centralized design paradigm: a user first uploads files to the server (cloud), and the server (cloud) re-distributes these files to other users, resulting in unnecessary tussles and inefficient data distribution paths. To bring the truly distributed file sharing back into the cyberspace, this paper presents Chrono Share, a distributed file sharing application built on top of the Named Data Networking (NDN) architecture. By walking through Chrono Share design details, we show how file sharing, as well as many other similar applications, can be effectively implemented over NDN in a truly distributed and secure manner.

SAIL: A scalable approach for wide-area IP mobility

The Internet is becoming increasingly mobile, with not only smartphones outnumbering stationary hosts, but also cars, buses, trains and airplanes all coming online. This makes Internet mobility support more important than ever. However the existing standard mobility support protocols, mainly Mobile IPv6 and Network Mobility (NEMO), suffer from triangle routing problem. In this paper we present a new mobility support protocol called SAIL that provides an effective and efficient solution to the triangle routing problem while being completely compatible with Mobile IP. SAIL is built upon the Global HAHA protocol which uses multiple distributed home agents to minimizes triangle routing, but removes its high overhead by one-hop DHT. We evaluate the SAIL design through extensive simulations and our results show that SAIL can provide superior performance over Mobile IP while keeping the overhead low.

Home as you go: an engineering approach to mobility-capable extended home networking

In this paper we describe and discuss the design choices of Apple Inc.s Back to My Mac (BTMM) service. BTMM provides an integrated solution to host mobility support, NAT traversal, and secure end-to-end data delivery through a combination of several existing protocols and software tools. We discuss BTMMs design tradeoffs and examine its applicability as a general solution to mobility-capable extended home networks.