Until late Thursday night, it was possible for Egyptian internet users to route their systems through openDNS and other open domain name system routing servers to gain access to the global internet.
Unfortunately it seems that LINKdotNET, Raya Telecom, Internet Egypt, Vodafone Egypt and IDSC disconnected their users as Friday progressed, with only Noor Data Networks reportedly now offering service.
According to Rik Ferguson, a senior security advisor with Trend Micro, Noor remains online as it is the ISP to the Egyptian Stock Exchange.
"The availability of this network and normal connectivity to the rest of the geographic region demonstrates that this is not a cut cable or other physical outage", he said in his security blog.
"Even the National Telecoms Regulatory Agency is currently unreachable as are most major news outlets, schools, businesses and official and unofficial information sources", he added.
Ferguson went on to say that, from his own tests, the top-level domain server at the Egyptian Universities Network cannot be resolved over DNS and does not respond to communications over TCP/IP, illustrating the effectiveness of this total shutdown using both domain name system (DNS) and border gateway protocol (BGP) approaches.
Infosecurity notes that this is the first time that a complete country has effectively severed its internet links with the outside world.
There are signs, however, that some internet users that connect via the Noor Data Networks service are allowing free access to the Net via WiFi connections without passwords.
There are also reports that some internet users have resorted to using dial-up modem connections via some of the old Sprintnet and Tymnet X.25 gateways in Cairo and other cities, although data speeds are quite low.