How Egypt shut down the internet

Virtually all internet access in Egypt is cut off today as the government battles to contain the street protests that threaten to topple President Hosni Mubarak.

Police fire tear gas towards protesters in Suez
Police fire tear gas towards protesters in Suez, Egypt Credit: Photo: AFP/GETTY

Organisations that track global internet access detected a collapse in traffic in to and out of Egypt at around 10.30GMT on Thursday night.

The shut down involved the withdrawal of more than 3,500 Border Gateway Protocol (BGP) routes by Egyptian ISPs, according to Renesys, a networking firm. Only one ISP out of 10, Noor Data Networks, appeared largely unaffected. It connects to the outside world via an undersea cable operated by Telecom Italia.

According to BGPMon, another networking firm, 88 per cent of Egyptian internet access was successfully shut down, however.

Renesys speculated that the apparent anomaly of Noor Data Networks may be a result of the fact it provides services to the Egyptian stock exchange.

BGP routes are one of the most vital parts of the internet. They are mostly used by ISPs so their networks can exchange information about how to best route the packets of data that make up all internet communications.

If an ISP withdraws its BGP routes, its customers effectively disappear from the internet, unable to access websites and services, send and receive email, or use voice services such as Skype.

The Egyptian government’s action is unprecedented in the history of the internet. Countries such as China, Iran, Thailand and Tunisia have cut off access to news websites and social networking services during periods of unrest, as Egypt did when it cut off Facebook and Twitter earlier this week.

The ongoing attempt by the Egyptian government to shut down all online communication is, however, a new phenomenon. It not only prevents ordinary Egyptian internet users from accessing any websites, it cripples Tor, an anti-censorship tool that technical experts and activists were using to circumvent the Facebook and Twitter blocks.

The action puts Egypt, temporarily at least, in the company of North Korea, which has never allowed its citizens access to the internet.