Jiachen Chen

COPSS: An Efficient Content Oriented Publish/Subscribe System

Content-Centric Networks (CCN) provide substantial flexibility for users to obtain information without regard to the source of the information or its current location. Publish/subscribe (pub/sub) systems have gained popularity in society to provide the convenience of removing the temporal dependency of the user having to indicate an interest each time he or she wants to receive a particular piece of related information. Currently, on the Internet, such pub/sub systems have been built on top of an IP-based network with the additional responsibility placed on the end-systems and servers to do the work of getting a piece of information to interested recipients. We propose Content-Oriented Pub/Sub System (COPSS) to achieve an efficient pub/sub capability for CCN. COPSS enhances the heretofore inherently pull-based CCN architectures proposed by integrating a push based multicast capability at the content-centric layer. We emulate an application that is particularly emblematic of a pub/sub environment -- Twitter -- but one where subscribers are interested in content (e.g., identified by keywords), rather than tweets from a particular individual. Using trace-driven simulation, we demonstrate that our architecture can achieve a scalable and efficient content centric pub/sub network. The simulator is parameterized using the results of careful micro benchmarking of the open source CCN implementation and of standard IP based forwarding. Our evaluations show that COPSS provides considerable performance improvements in terms of aggregate network load, publisher load and subscriber experience compared to that of a traditional IP infrastructure.

G-COPSS: A content centric communication infrastructure for gaming applications

With users increasingly focused on an online world, an emerging challenge for the network infrastructure is the need to support Massively Multiplayer Online Role Playing Games (MMORPG). This is an application domain that is attracting more players than ever before, very often with players distributed over a metropolitan area. Currently, MMORPG are built on an IP infrastructure with the primary responsibility on servers to do the work of disseminating control messages and having to predict/retrieve objects in each players view. Limited server resources significantly impair the users interactive experience. Modern fast-paced action games that run on a client/server architecture limit the number of players who can interact simultaneously since the server needs to handle the frequent updates and disseminate them. Scale and timeliness are major challenges of such a server-oriented gaming architecture. We propose Gaming over COPSS (G-COPSS), a communication infrastructure using a Content-Oriented Pub/Sub System (COPSS) to enable efficient decentralized information dissemination in MMORPG, exploiting the network and the end-systems for player management and information dissemination. We emulate an application that is particularly emblematic of MMORPG — Counter-Strike — but one in which all the players share a hierarchical structured map. Using trace-driven simulation, we demonstrate that G-COPSS can achieve high scalability and tight timeliness requirements of MMORPG. The simulator is parameterized using the results of careful microbenchmarking of the open-source CCN implementation and of standard IP-based forwarding. Our evaluations show that G-COPSS provides considerable performance improvement in terms of aggregate network load and update latency compared to that of a traditional IP server-based infrastructure.

Comparison of naming schema in ICN

Information-Centric Networking (ICN) treats content as a first-class entity - each content has a unique identity and ICN routers forward traffic based on content identity rather than the locations of the content. This provides benefits like dynamic request routing, caching and mobility support. The choice of naming schema (flat vs. hierarchical) is a fundamental design choice in ICN which determines the functional separation between the network layer and the application layer. With hierarchical names, the network layer is cognizant of the semantics of hierarchical names. Name space management is also part of network layer. ICN architectures using flat names leave these to the application layer. The naming schema affects the performance and scalability of the network in terms of forwarding efficiency, routing table size and name space size. This paper provides both qualitative and quantitative comparison on the two naming schemas using these metrics, noting that they are interdependent. We seek to understand which naming schema would be better for a high-performance, scalable ICN architecture.

SAID: A Control Protocol for Scalable and Adaptive Information Dissemination in ICN

Information dissemination applications (video, news, social media, etc.) with large number of receivers need to be efficient but also have limited loss tolerance. The Information Centric Networks (ICN) paradigm offers an alternative approach for reliably delivering data by naming content and exploiting data available at any intermediate point (e.g., caches). However, receivers are often heterogeneous, with widely varying receive rates. When using existing ICN congestion control mechanisms with in-sequence delivery, a particularly thorny problem of receivers going out-of-synch results in inefficiency and unfairness with heterogeneous receivers. We argue that separating reliability from congestion control leads to more scalable, efficient and fair data dissemination, and propose SAID, a control protocol for Scalable and Adaptive Information Dissemination in ICN. To maximize the amount of data transmitted at the first attempt, receivers request any next packet (ANP) of a flow instead of next-in-sequence packet, independent of the provider’s transmit rate. This allows providers to transmit at an application-efficient rate, without being limited by the slower receivers. SAID ensures reliable delivery to all receivers eventually, by cooperative repair, while preserving privacy without unduly trusting other receivers.

Coexist: integrating content oriented publish/subscribe systems with ip

Content-Centric Networking (CCN) seeks to meet the content-centric needs of users. In this paper, we propose hybrid-COPSS, a hybrid content-centric architecture. We build on the previously proposed Content-Oriented Publish/Subscribe System (COPSS) to address incremental deployment of CCN and elegantly combine the functionality of content-centric networks with the efficiency of IP-based forwarding including IP multicast. Furthermore, we propose an approach for incremental deployment of caches in generic query/response CCN environments that optimizes latency and network load. To overcome the lack of inter-domain IP multicast, hybrid-COPSS uses COPSS multicast with shortcuts in the CCN overlay. Our hybrid approach would also be applicable to the Named Data Networking framework. To demonstrate the benefits of hybrid-COPSS, we use a multiplayer online gaming trace in our lab test-bed and microbenchmark the forwarding performance and queuing for both COPSS and hybrid-COPSS. A large scale trace-driven simulation (parameterized by the microbenchmark) on a representative ISP topology was used to evaluate the response latency and aggregate network load. Our results show that hybrid-COPSS performs better in terms of response latency in a single domain. In a multi-domain environment, hybrid-COPSS significantly reduces update latency and inter-domain traffic.

Prototype of an ICN based approach for flexible service chaining in SDN

With the widespread use of middleboxes in communication networks (e.g., for services such as Firewall, DPI, accounting, proxies, caching), additional processing beyond simple forwarding has become common. With the emergence of Network Function Virtualization (NFV), dynamically instantiating these functions becomes even more feasible. In addition, chaining such services for packet flows is key to efficiently delivering Internet services. In addition, Software Defined Networking (SDN) gives Internet Service Providers greater flexibility to provision such middlebox based services and route flows through them. However, with the dynamic instantiation of network functions, efficient and scalable use of these services requires separation of the services from their location. In this work, we implement and demonstrate an Information Centric Networking based solution that complements SDN for service chaining and provides benefits such as scalability, flexibility and reliability.

ORICE: an architecture for object resolution services in information-centric environment

Information Centric Networks (ICN) enable accessing data oblivious of its location, by allowing end-systems to retrieve content based on names. But, architectures such as Named Data Networking (NDN) and Content Oriented Publish/Subscribe System (COPSS) do not yet provide a mechanism for end-system applications to obtain these names. There is a need for an object resolution system that addresses a most important and as yet unimplemented component of obtaining a name in ICN. In this paper, we propose ORICE, an architectural design for Object Resolution services in Information-Centric Environment that satisfies this need. The architecture enables intelligent resolution service by placing the service in the application layer and allows for the service diversity by separating the name space management from resolution service. Through preliminary evaluation, we show that with the help of ORICE, the states stored in the network can be dramatically reduced while ensuring complete data delivery.

Coexist: a hybrid approach for content oriented publish/subscribe systems

Content Centric Networking (CCN) is a new paradigm that addresses the gap between the content-centric needs of a user and the current widespread location-centric IP network architecture. In this paper, we propose a hybrid content centric architecture based on our pub/sub enhancement to CCN, Content-Oriented Publish/Subscribe System (COPSS). Our hybrid architecture (hybrid-COPSS) addresses both the need for incremental deployment of CCN and also elegantly combines the functionality of content centric networks and the efficiency of IP forwarding. Our architecture integrates IP multicast to achieve forwarding efficiency by taking advantage of shortest path routing. To overcome the lack of inter-domain IP multicast, hybrid-COPSS uses COPSS multicast with shortcuts as an overlay and IP multicast as the underlay to achieve inter-domain COPSS multicast. To demonstrate the benefits of our hybrid-COPSS architecture, we study its applicability for online gaming, which typically requires low latency. We use a gaming trace in our lab test-bed and microbenchmark the forwarding performance and queuing for a pure COPSS (representative of a pure CCN) based network versus hybrid-COPSS. Also, a large scale simulation (parameterized by the microbenchmark) on a representative ISP topology was used to evaluate the response latency and aggregate network load for the multi-player online gaming scenario. Our preliminary results show that hybrid-COPSS performs better in terms of response latency compare to pure COPSS in a single domain. In a multi-domain environment, hybrid-COPSS can significantly reduce inter-domain traffic while causing only a small increase in the average response latency.

CNS: Content-oriented Notification Service for Managing Disasters

Disaster management critically depends on timely and efficient communication. To better deal with an incident, authorities from different services (e.g., fire, police) and jurisdictions need to work together in a new dynamically created team, different from their original organizational/administrative hierarchy. Unfortunately, existing solutions (e.g., IP, or traditional telephony) are not well-suited to deal with such group communication due to the dynamic binding between roles and individuals, and mobility. A significant burden is placed on administrators to just establish and maintain necessary channels, distracting them from restoring order. To make things worse, since senders do not know which individual(s) to send to, information cannot reach the right people, delaying rescue efforts. We propose CNS, leveraging the benefits of ICN to provide the essential communication for efficiently managing disasters. We first design a namespace enabling dynamic creation and evolution of incident related (sub-)namespaces to represent roles of first responders assigned to the disaster. This allows first responders to receive the appropriate information on a timely basis, with senders addressing the recipients based on their roles. Predefined namespace templates for disaster types minimize management overhead for establishing communication. We also find the need for a new enhanced forwarding rule to support such a recipient hierarchy. We have developed a prototype demonstrating feasibility and efficiency. With the help of large-scale simulations and real-world disaster traces, we compare CNS with an IP-based solution. CNS can significantly reduce network load and latency in addition to the qualitative benefits of simplified operations, appropriate prioritization and security.

VDR: A Virtual Domain-Based Routing Scheme for CCN

In this work, we propose VDR, a routing scheme based on virtual domains -- domains that are not bound to physical routers -- to exploit the benefits of aggregation and hashing while overcoming their disadvantages. VDR addresses the FIB scalability issue in CCN by facilitating aggregation without compromising on the advantages of CCN such as ease of data replication and obtaining the data from a closer source. Our preliminary evaluation shows that VDR lowers the number of FIB entries present at a router significantly without compromising much on path stretch.