Category Archives: Internet Outages

Syria and Yemen: 29 November 2012

At 10:30 AM GMT yesterday, 29 November 2012, routing to Yemen suddenly changed from London to Dubai through FLAG to New York to Dubai through ETISALAT, as shown in the animation here and detailed in the PerilWatch from InternetPerils. That timing closely matched the 10:26 AM GMT Syrian disconnect time reported by Renesys. This is very reminiscent of Mubarak disconnecting Egypt 22:30 GMT 20 January 2011. This tactic didn’t help Mubarak’s regime in Egypt, and it probably won’t help Assad’s regime in Syria; rather the opposite: people don’t like their Internet being turned off. And it tends to cause the international community to rally around the rebels.


Egypt Returns

Egypt returned to the Internet about 09:30 GMT today (2 February 2011). This sudden return after being as suddenly disconnected one week ago (27 January 2011) is obviously not due to ordinary causes such as congestion, cable cut, or router failure. This political disconnection of an entire country does not seem to have helped the regime responsible for it; quite the opposite.


NANOG: Botnets, DDoS and Ground-Truth

Here at NANOG 50 Craig Labovitz just gave an interesting talk about botnet data derived from Arbor Network customers enabling anonymous data (37 ISPs over last 12 months), of 5,000 events classified by operators.

60% of DDoS attacks are by flooding. Yet most attacks involve few IP addresses; indicates address spoofing.

Slight problem: only 1/4 of customers have enabled anonymous data. “Real goal of this talk is to encourage participation.”

Well-received talk.


Route Hijacking: Identity Theft of Internet Infrastructure

Peter Svensson gives an old and quite serious problem some mainstream press in this AP story from 8 May 2010:
On April 25, 1997, millions of people in North America lost access to all of the Internet for about an hour. The hijacking was caused by an employee misprogramming a router, a computer that directs data traffic, at a small Internet service provider.

A similar incident happened elsewhere the next year, and the one after that. Routing errors also blocked Internet access in different parts of the world, often for millions of people, in 2001, 2004, 2005, 2006, 2008 and 2009. Last month a Chinese Internet service provider halted access from around the world to a vast number of sites, including and, for about 20 minutes.

In 2008, Pakistan Telecom tried to comply with a government order to prevent access to YouTube from the country and intentionally “black-holed” requests for YouTube videos from Pakistani Internet users. But it also accidentally told the international carrier upstream from it that “I’m the best route to YouTube, so send all YouTube traffic to me.” The upstream carrier accepted the routing message, and passed it along to other carriers across the world, which started sending all requests for YouTube videos to Pakistan Telecom. Soon, even Internet users in the U.S. were deprived of videos of singing cats and skateboarding dogs for a few hours.

In 2004, the flaw was put to malicious use when someone got a computer in Malaysia to tell Internet service providers that it was part of Yahoo Inc. A flood of spam was sent out, appearing to come from Yahoo.

The Pakistani incident is illustrated in the accompanying story and video by RIPE.

This problem has been known for a long time. Why hasn’t it been fixed? Continue reading

Community Flow-spec Project

A lightning talk at NANOG 48, Austin, Texas, 22 Feb 2010, by John Kristoff, Team Cymru. See RFC 5575.

Update: PDF of presentation slides here.

| type   | extended community | encoding                 |
| 0x8006 | traffic-rate       | 2-byte as#, 4-byte float |
| 0x8007 | traffic-action     | bitmask                  |
| 0x8008 | redirect           | 6-byte Route Target      |
| 0x8009 | traffic-marking    | DSCP value               |

A few selected points:

  • Dissemination of Flow Specification Rules
  • Think of filters(ACLs) distributed via BGP
  • BGP possibly not the right mechanism
  • Multi-hop real-time black hole on steroids
  • Abuse Handler + Peering Coordinator
    = Abeering Coordinator?
  • Traditional bogon feed as source prefix flow routes
  • A la carte feeds (troublesome IP multicast groups, etc.)
  • AS path prepend++
  • Feed-specific community + no-export
He showed some examples of specs for flows (I can’t type fast enough to transcribe those).

Trust issues for routes defined by victim networks.

Research prototype is set up. For questions, comments, setup, contact:

I like it as an example of collective action against the bad guys. How to deal with the trust issues seems the biggest item to me.

Hm, at least to the participating community, this is a reputation system.

Iranian Internet Disturbances

iran20090615.gif Here’s an example of some Internet routing in Iran, in this case on the way to the Ministry of Foreign Affairs on Monday 15 June 2009. Normally, routing and latency don’t change much. Starting Saturday 13 June, the day after the election, routing and latency have become increasingly disturbed. More here.

Van Meter on Barabasi and Doyle on Internet topology and risks

rdv-hakama-0609.jpg Rodney Van Meter, co-teaching a class by Jun Murai, posts notes on why Albert-László Barabási (ALB) is both right and wrong about the Internet (it is more or less a scale-free network when considered as a network of Autonomous Systems (AS), but contrary to ALB's assumption John Doyle and others have pointed out that the bigger nodes are not central, an AS as a node would be somewhat difficult to take out all at once, there are both higher and lower layer topologies that make the Internet more robust, and the Internet's biggest problem isn't topology at all:

The most serious risks to the Internet are not to individual "nodes" (ASes), but rather stem from the near-monocropping of Internet infrastructure and end nodes, and the vulnerability of the system to human error (and political/economic considerations):

Monoculture, who would have thought it?

For that matter, the Internet's ability to reroute has been very useful to ameliorate topological link breaks at the physical layer, for example undersea cables in the Mediterranean Sea twice last year.

U.A.E. Cable Cut of 30 Jan 2008

There’s been a lot of talk about the numerous cable cuts in the Mediterranean Sea and the Persian Gulf in the past few weeks. It’s interesting to see the Internet route around damage. Here is a visualization of the first cable cut, off Alexandria, on 30 Jan 2008.


Common Sense Lacking for Big Perils such as Georgia Hurricane or WorstCase Worm

KClark.jpg Why it’s not good to depend on common sense for really big perils:
The models these companies created differed from peril to peril, but they all had one thing in common: they accepted that the past was an imperfect guide to the future. No hurricane has hit the coast of Georgia, for instance, since detailed records have been kept. And so if you relied solely on the past, you would predict that no hurricane ever will hit the Georgia coast. But that makes no sense: the coastline above, in South Carolina, and below, in Florida, has been ravaged by storms. You are dealing with a physical process, says Robert Muir-Wood, the chief scientist for R.M.S. There is no physical reason why Georgia has not been hit. Georgias just been lucky. To evaluate the threat to a Georgia beach house, you need to see through Georgias luck. To do this, the R.M.S. modeler creates a history that never happened: he uses what he knows about actual hurricanes, plus what he knows about the forces that create and fuel hurricanes, to invent a 100,000-year history of hurricanes. Real history serves as a guide it enables him to see, for instance, that the odds of big hurricanes making landfall north of Cape Hatteras are far below the odds of them striking south of Cape Hatteras. It allows him to assign different odds to different stretches of coastline without making the random distinctions that actual hurricanes have made in the last 100 years. Generate a few hundred thousand hurricanes, and you generate not only dozens of massive hurricanes that hit Georgia but also a few that hit, say, Rhode Island.

In Nature’s Casino, By Michael Lewis, New York Times, August 26, 2007

And of course a hurricane did hit the Georgia coast before detailed records were kept, in 1898. The article notes that before Hurricane Andrew, insurers believed that a Florida hurricane would cost max a few billion. The actual cost was more like $15.5 billion, predicted only by one woman: Karen Clark, founder of A.I.R.

Sure, the Georgia coast doesn’t have any single concentration of wealth like Miami. But it does have a swath of wealth that could be taken down by a single storm. And complacent owners who think it can’t ever happen, just like people in Thailand didn’t believe Smith Dharmasaroja before the 2004 Tsunami.

Meanwhile, on the Internet, the few insurers of Internet business continuity are winging it and most companies have no insurance at all, despite online crime becoming increasingly sophisticated, leveraging the global reach of the Internet, and the possibility of a global worm that could cause $100 billion damage still being out there.

-jsq .