Sago : Resource Virtualization Techniques in Wide-Area Overlay Networks

Faculty:
Tzi-cker Chiueh

Member:
Kartik Gopalan

Project Description

An emerging trend in large organizations is to out-source computing and communication services to service providers ranging from basic connectivity (ISP) and storage management (SSP) to end-to-end application deployment and hosting (ASP). The central technical problem that all xSPs face is how to multiplex multiple logical resource entities, each corresponding to a distinct customer, on a single physical resource in a way that conforms to individual customer's service level agreement (SLA) and that at the same time achieves the highest system utilization efficiency.

In this project, we focus on resource virtualization techniques for wide-area networks. We propose an overlay network resource management system called Sago that allocates, provisions, and manages virtual overlay networks on a single physical network such that each overlay network can have its own performance and reliability qualities of service (QoS), as well as data-plane/control-plane processing.

In the Sago project, we start with a given baseline network, and virtualize it into multiple overlay networks. Each overlay network belongs to a separate administrative domain and thus is completely isolated from the others in terms of performance behavior and packet processing functionality. The baseline network could be a physical network, or itself a logical network. Sago consists of two components, a global resource manager (GRM), which oversees the allocation of node and link resources on the baseline network, and a local packet processing engine (LPPE), which is placed at each baseline network node and performs actual resource usage control and management at run time.

In Sago, users can specify an overlay network along the following dimensions:

• The overlay network topology, where every overlay network's node has to be a member of the baseline network node set.
• The bandwidth and delay characteristic for every overlay network link in each direction.
• The reliability requirement for each overlay network link.
• The data-plane/control-plane packet processing functions to be deployed on each overlay network node.

There are several important research issues that we focus on in the Sago project.

• A logical to physical network resource mapping algorithm that maximizes the overall system resource utilization efficiency by taking into account both the static baseline network topology and the dynamic input request workload distribution. What network resource mapping algorithm is to overlay network management is what page mapping algorithm is to virtual memory management.
• A comprehensive fault tolerance strategy for setting up wide-area overlay networks that are tolerant of both node failures and link failures, and that cover both network-layer and transport-layer states.
• An overlay network management system architecture that supports the most general and flexible form of virtual network specification, and that can effectively enforce both CPU/network resource usage at run time according to the specifications.

  
Publications

• "Efficient Provisioning Algorithms for Network Resource Virtualization with QoS Guarantees", Kartik Gopalan, Ph.D. Thesis, Department of Computer Science, State University of New York at Stony Brook, July 2003.
• Resource Virtualization Techniques for Wide-Area Overlay Networks - Technical Report.
• Measurement-based Per-flow Statistical Delay Guarantees, Kartik Gopalan and Tzi-cker Chiueh, 2nd New York Metro Area Networking Workshop, Columbia University, New York, NY, September 2002.
• Delay Budget Allocation for Delay Bounded Network Paths - Technical Report.
• Slides from WIP presentation at USENIX 2002, Monterey, CA