Archive for March 21st, 2012

How to mitigate the “hidden risk of meltdown…”

Wednesday, March 21st, 2012 by Antonio Manzalini

Network are becoming more and more complex and dynamic, capable of interconnecting large numbers of resources (e.g., routers, switches, transport nodes, servers…), Users’ devices (e.g., smart phones, etc) and, in the future, any machines (e.g. sensors, smart things, etc) embedding communication capabilities.

Future networks will be similar to complex systems where global properties and effects can emerge abruptly at a critical level of interactions between their components. In these dynamics, there is the hidden risk of instabilities. Overall, instability may have primary effects both jeopardizing the network performance  and compromising an optimized use of resources. In the worst case, an instability may create even a meltdown of a portion of network.

This is the main problem which I’ve proposed for study (more or less on year ago) in the EU project Univerself as part of the Telecom Italia participation in the project. Basically, we’re looking for methods and systems able to ensure network stability through local self-adaptation of nodes and, if-when not sufficient, via centralized policy based control.

This morning I’ve been very pleased to read this interesting paper Icebergs in the Clouds: the Other Risks of Cloud Computing addressing the risk of instabilities on the Cloud, which is essentially a metaphor for a network of computing and storage entities in which tasks and resources can be shared.

Example instability risk from unintended coupling of independently developed reactive controllers

Paper points out that complex systems can fail in many unexpected ways and outlines various simple scenarios. In the worst case, a cloud could experience a full meltdown that could seriously threaten any business that relies on it. Well, this is very much the same for future networks!

A growing number of researchers are beginning to see this problem: unpredictable behaviors often emerges in systems made up of “networks of networks”.

Paper concludes with the following: “We should study [these unrecognised risks] before our socioeconomic fabric becomes inextricably dependent on a convenient but potentially unstable computing model.”