February 20, 2011

Georedundancy and Service Availability Proposal

  • Adams R.
  • Bauer E.
  • Eustace D.

A best practice for mitigating the risk of site destruction, denial or unavailability causing disastrous loss of critical services is to deploy redundant systems in a geographically separated location; this practice is called geographic redundancy or georedundancy. Enterprises deploying a geographically redundant system may spend twice as much as for a standalone configuration up front, and will have higher on going operating expenses to maintain the redundant recovery site. While the business continuity benefits of georedundancy are easy to understand, the feasible and likely service availability benefits of georedundancy are not generally well understood. This paper considers the high level question of what service availability improvement is feasible and likely with georedundancy. The service availability benefit is characterized both for product attributable failures, as well as for non-product attributable failures, including site disasters. Furthermore, this paper considers other topics, such as whether georedundancy can/should be used to reduce planned downtime for activities such as hardware growth and software update, whether it is better to only do a georedundancy failover for a failed element or for an entire cluster that contains the failed element, what availability-related georedundancy requirements should apply to each network element and to clusters of elements, and what network element and cluster testing is appropriate to assure expected service availability benefits of georedundancy.

Recent Publications

August 09, 2017

A Cloud Native Approach to 5G Network Slicing

  • Francini A.
  • Miller R.
  • Sharma S.

5G networks will have to support a set of very diverse and often extreme requirements. Network slicing offers an effective way to unlock the full potential of 5G networks and meet those requirements on a shared network infrastructure. This paper presents a cloud native approach to network slicing. The cloud ...

August 01, 2017

Modeling and simulation of RSOA with a dual-electrode configuration

  • De Valicourt G.
  • Liu Z.
  • Violas M.
  • Wang H.
  • Wu Q.

Based on the physical model of a bulk reflective semiconductor optical amplifier (RSOA) used as a modulator in radio over fiber (RoF) links, the distributions of carrier density, signal photon density, and amplified spontaneous emission photon density are demonstrated. One of limits in the use of RSOA is the lower ...

July 12, 2017

PrivApprox: Privacy-Preserving Stream Analytics

  • Chen R.
  • Christof Fetzer
  • Le D.
  • Martin Beck
  • Pramod Bhatotia
  • Thorsten Strufe

How to preserve users' privacy while supporting high-utility analytics for low-latency stream processing? To answer this question: we describe the design, implementation and evaluation of PRIVAPPROX, a data analytics system for privacy-preserving stream processing. PRIVAPPROX provides three properties: (i) Privacy: zero-knowledge privacy (ezk) guarantees for users, a privacy bound tighter ...