SecondNet

TLDR

Virtual data centers are preferred over physical ones because their resources can be rapidly adjusted to meet tenants’ changing needs. The paper proposes virtual data centers as the unit of resource allocation for multiple tenants and introduces SecondNet, a data center network virtualization architecture to enable this abstraction. SecondNet distributes virtual‑to‑physical mapping, routing, and bandwidth reservation state across server hypervisors, uses port‑switching based source routing to support arbitrary topologies on commodity hardware, and employs a centralized VDC allocation algorithm to guarantee bandwidth. Simulations and experiments demonstrate that SecondNet achieves high network utilization, low time complexity, bandwidth guarantees, and elasticity across various network topologies.

Abstract

In this paper, we propose virtual data center (VDC) as the unit of resource allocation for multiple tenants in the cloud. VDCs are more desirable than physical data centers because the resources allocated to VDCs can be rapidly adjusted as tenants' needs change. To enable the VDC abstraction, we design a data center network virtualization architecture called SecondNet. SecondNet achieves scalability by distributing all the virtual-to-physical mapping, routing, and bandwidth reservation state in server hypervisors. Its port-switching based source routing (PSSR) further makes SecondNet applicable to arbitrary network topologies using commodity servers and switches. SecondNet introduces a centralized VDC allocation algorithm for bandwidth guaranteed virtual to physical mapping. Simulations demonstrate that our VDC allocation achieves high network utilization and low time complexity. Our implementation and experiments show that we can build SecondNet on top of various network topologies, and SecondNet provides bandwidth guarantee and elasticity, as designed.