Yuan Yang

• PhD
• Assistant reseacher at Tsinghua University

The rapid growth of global modern wide area networks has posed significant challenges to traffic engineering (TE). Existing TE methods often struggle to balance optimality with tractability, while recent machine learning based approaches fail to develop reliable strategies across diverse network scenarios. To address these issues, we introduce LO-T...

Traffic engineering (TE) has attracted extensive attention over the years. Operators expect to design a TE scheme that accommodates traffic dynamics well and achieves good TE performance with little overhead. Some approaches like oblivious routing compute an optimal static routing based on a large traffic matrix (TM) range, which usually leads to m...

Border Gateway Protocol (BGP) is the only inter-domain routing protocol that plays an important role on the Internet. However, BGP suffers from route leaks, which can cause serious security threats. To mitigate the effects of route leaks, accurate and timely route leak locating is of great importance. Prior studies leverage AS business relationship...

IPv6 has shown notable growth in recent years, imposing the need for high-speed IPv6 lookup. As the forwarding rate of virtual switches continues increasing, software-based IPv6 lookup without using special hardware such as TCAM, GPU, and FPGA is of academic interest and industrial importance. Existing studies achieve fast software IPv4 lookup by r...

Ternary Content Addressable Memory (TCAM) enables fast lookup and is widely used by routers and switches to support policy-based forwarding. Due to high cost and small capacity, only a small subset of important rules can be cached in TCAM, so determining it is critical to increasing the hit ratio. This is more challenging than traditional caching p...

The Domain Name System (DNS) is a growing center of cyber attacks, including both volumetric and non-volumetric attacks. Programmable switches provide a new opportunity for more efficient defense against DNS attacks since they can offer better cost, performance, and flexibility trade-offs compared to traditional defense systems. However, programmab...

To improve the performance of mobile web services, a new transport protocol, QUIC, has been recently proposed as a substitute for TCP. However, with pros and cons of QUIC, it is challenging to decide whether and when to use QUIC in large-scale real-world mobile web services. Complex temporal correlation of network conditions, high user heterogeneit...

With the rapid growth of backbone networks and data center networks, ensuring network robustness under various failure scenarios has become a key challenge in network design. The combinatorial nature of failure scenarios in data plane, control plane, and management plane seriously challenges existing practice on robust network design, which often r...

Emerging applications raise critical QoS requirements for the Internet. The improvements in flow classification technologies, software-defined networks (SDN), and programmable network devices make it possible to fast identify users' requirements and control the routing for fine-grained traffic flows. Meanwhile, the problem of optimizing the forward...

Robust network design, which aims to guarantee network availability under various failure scenarios while optimizing performance/cost objectives, has received significant attention. Existing approaches often rely on model-based mixed-integer optimization that is hard to scale or employ deep learning to solve specific engineering problems yet with l...

Providing provable performance guarantees in vehicular network routing problems is crucial to ensure safely and timely delivery of information in an environment characterized by high mobility, dynamic network conditions, and frequent topology changes. While Reinforcement Learning (RL) has shown great promise in network routing, existing RL-based so...

Robust network design, which aims to guarantee network availability under various failure scenarios while optimizing performance/cost objectives, has received significant attention. Existing approaches often rely on model-based mixed-integer optimization that is hard to scale or employ deep learning to solve specific engineering problems yet with l...

p>This work is under review of IEEE Transactions on Parallel and Distributed Systems. </h3

p>This work is under review of IEEE Transactions on Parallel and Distributed Systems. </h3

Software-Defined Networking (SDN). SDN enables network innovations with a centralized controller controlling the whole network through the control channel. Because the control channel delivers all network control traffic, its security and reliability are of great importance. For the first time in the literature, we propose the CrossPath attack that...

Network Function Virtualization (NFV) is a new networking paradigm to enable dynamic network function deployment in networks. Existing studies focused on optimized function deployment and management in NFV. Unfortunately, these studies did not well address the problem of efficient security function enforcement in networks, which is the goal of depl...

The emerging Software-Defined Networking (SDN) is being adopted by data centers and cloud service providers to enable flexible control. Meanwhile, the current SDN design brings new vulnerabilities. In this paper, we explore a stealthy attack that uses a minimum rate of attack packets to disrupt SDN data plane. To achieve this, we propose the LOFT a...

In many real-world tasks, a team of learning agents must ensure that their optimized policies collectively satisfy required peak and average constraints, while acting in a decentralized manner. In this paper, we consider the problem of multi-agent reinforcement learning for a constrained, partially observable Markov decision process – where the age...

Existing solutions of flow-level traffic engineering (TE) usually depend on the deployment of SDN or MPLS. In this paper, we design a flow-level and efficient TE scheme based on the conventional hop-by-hop routing protocol, i.e., OSPF. Motivated by the analysis and modeling on the real Internet traffic, we propose to detect and schedule a few large...

Load balancing in datacenter networks (DCNs) is an important and challenging task for datacenter managers. A number of sophisticated technologies have been proposed to improve load balancing performance in a complicated circumstance, i.e., with various traffic characteristics. Many approaches need a high cost to implement, such as changing switch h...

This chapter analyzes the overall trend of Internet development, and discusses the research and development effort on new network architectures. Further, the chapter summarizes the development trend of Internet in China and proposes some suggestions on the future Internet development.

Demand-oblivious routing has become a promising technology for traffic engineering, since there is no need to estimate or measure traffic volume precisely, and network congestion in the worst case can be bounded. An important issue for demand-oblivious routing is to deal with topology changes, and there have been studies on demand-oblivious routing...

Network function virtualization (NFV) is a technology that realizes network functions based on virtualization technology and standard commercial servers, switches, and storage, so as to substitute traditional middleboxes that are dedicated devices. NFV is proposed to save construction and operation cost for network service providers. NFV can also i...

Multi-link failures may incur heavy packet loss and degrade the network performance. Fast rerouting has been proposed to address this issue by enabling routing protections. However, the effectiveness and efficiency issues of fast rerouting are not well addressed. In particular, the protection performance of existing approaches is not satisfactory e...

Constructing an integrated terrestrial and space network is one of the key projects in China. Heterogeneous networks can be efficiently integrated using the IP protocol family in space networks to leverage the advantages of the Internet. However, traditional routing techniques cannot be used directly due to the special characteristics of space netw...

Distributed Software Defined Networking (SDN) federates multiple controllers in a network to solve the problems in single controller networks, e.g., to improve network reliability and reduce the delay between controllers and switches. However, in the current distributed SDN schemes, the mapping between SDN switches and controllers is statically con...

As the popularity of content-delivery applications (e.g., YouTube) grows, the inefficiency of transmission on the Internet has emerged, since in the TCP/IP networks, routers are unaware of the passing contents and the same content might be transmitted through the same path multiple times. To solve the problem as well as other problems, a lot of Inf...

Satellite networks are drawing more and more attention, since they can provide various services to everywhere on the earth. Communication devices in satellites are typically powered by solar panels and battery cells, which are designed carefully to guarantee power supply and avoid deficiency. However, we find that unrestrained use of energy will ca...

Measurement on the Border Gateway Protocol (BGP) system is important for understanding the Internet. Many attempts have been made to detect anomalous Internet events through dissecting BGP updates and tables. We notice that most works in this field either deploy/use few monitors or analyze aggregated statistics. Such practices may result in overest...

Network virtualization is a promising way for network innovation. Efforts have been made to develop virtual network platforms for both network researches and business applications. In this paper, we aim to provide a new solution to address the shortcomings of existing solutions. We propose MAVIN - a MAC address coding based virtual network platform...

The scalability and mobility issues in current Internet architecture have drawn a lot of attentions from researchers. However, there are still many problems in current solutions. In this paper, we argue that three spaces, i.e., endpoint IDentifier (ID), Endpoint Locator (ELoc) and Routing Locator (RLoc), are necessary to realize two separations, i....

Ternary Content Addressable Memory(TCAM)-based multidimensional tables are widely used to implement Access Control Lists (ACLs) for Internet packet classification and filtering, and have also become attractive for constructing the forwarding tables of Internet routers and the flow tables of Openflow switches, where multiple fields are generally use...

In this paper we study energy conservation in the Internet. We observe that different traffic volumes on a link can result in different energy consumption; this is mainly due to such technologies as trunking (IEEE 802.1AX), adaptive link rates, etc. We design a green Internet routing scheme, where the routing can lead traffic in a way that is green...

The Internet is generally not energy-efficient since all network devices are running all the time and only a small fraction of consumed power is actually related to traffic forwarding. Existing studies try to detour around links and nodes during traffic forwarding to save powers for energy-efficient routing. However, energy-efficient routing in tra...

The inefficiency of energy usage on the Internet has become a critical problem with its rapid growth, as all network devices operate at full capacity in spite of the real traffic load. Existing studies try to develop energy efficient routings by aggregating traffic and switching underutilized devices into sleep mode. However, most existing approach...

Information-centric networking (ICN) is a clean-slate network architecture to achieve efficient content transmissions. In-network caching is an important issue in ICN, since the routers have a limited caching capacity. Several approaches have been proposed to reduce the cache redundancy, and increase the cache hit ratio and the user delay. Most app...

In this paper we study energy conservation in the Internet. We observe that different traffic volumes on a link can result in different energy consumption; this is mainly due to such technologies as trunking (IEEE 802.1AX), adaptive link rates, etc. We design a green Internet routing scheme, where the routing can lead traffic in a way that is green...

Routing failures are common on the Internet and routing protocols can not always react fast enough to recover from them, which usually cause packet delivery failures. To address the problem, fast reroute solutions have been proposed to guarantee reroute path availability and to avoid high packet loss after network failures. However, existing soluti...

IP Fast ReRoute (IPFRR) has received increasing attention as a means to effectively shorten traffic disruption under failures. A major approach to implementing IPFRR is to pre-calculate backup paths for nodes and links. However, it may not be easy to deploy such an approach in practice due to the tremendous computational overhead. Thus, a light-wei...

Network failures occur frequently, and self-healing ability of existing routing protocols cannot guarantee fast route convergence under these failures without impacting packet forwarding. During routing convergence, network routes may be incorrect and even routing black holes and loops occur, which will result in extensive packet loss and thus infl...

Network failures occur frequently, and self-healing ability of existing routing protocols cannot guar-antee fast route convergence under these failures without impacting packet forwarding. During routing con-vergence, network routes may be incorrect and even routing black holes and loops occur, which will result in extensive packet loss and thus in...

IP Fast ReRoute (IPFRR) has received increasing attention as a means to effectively shorten traffic disruption under failures. A major approach for IPFRR is to pre-calculate backup paths for nodes and links. Such approach is, however, hard to deploy due to the tremendous computational overhead. Thus, a lightweight IPFRR scheme is desired to effecti...