Now, it's unlikely that it will break. Indeed, researchers publishing under the imprimatur of the The European Network and Information Security Agency (ENISA) say as much in the opening of their report from last month on the “Resilience of the Internet Interconnection Ecosystem” [5.8 mb PDF]. (You do know that the Internet is not, in fact, one network but is, instead, the ultimate network of networks. I continue to argue with copy editors that the Internet, for that reason, should always be capitalized for the term describes only one thing and one specific thing — much like the third planet from the Sun which is always called Earth … but I digress). Hurricane Katrina, terrorist attacks, Mafiaboy — you name it — nothing has been able to bring the Internet to its knees … at least so far [pdf]…
…it does appear likely that the Internet could suffer systemic failure, leading perhaps to local failures and system‐wide congestion, in some circumstances including:
- A regional failure of the physical infrastructure on which it depends (such as the bulk power transmission system) or the human infrastructure needed to maintain it (for example if pandemic flu causes millions of people to stay at home out of fear of infection).
- Cascading technical failures, of which some of the more likely near‐term scenarios relate to the imminent changeover from IPv4 to IPv6; common‐mode failures involving updates to popular makes of router (or PC) may also fall under this heading.
- A coordinated attack in which a capable opponent disrupts the BGP fabric by broadcasting thousands of bogus routes, either via a large AS or from a large number of compromised routers.
There is evidence that implementations of the Border Gateway Protocol (BGP) are surprisingly fragile. There is evidence that some concentrations of infrastructure are vulnerable and significant disruption can be caused by localised failure. There is evidence that the health of the interconnection system as a whole is not high among the concerns of the networks that make up that system – by and large each network strives to provide a service which is reliable, most of the time, at minimum achievable cost. The economics do not favour high dependability as there is no incentive for anyone to provide the extra capacity that would be needed to deal with large‐scale failures.