Its very practical for a country to cut 95%+ of its Internet connectivity. Its not a complete cut-off, there is some limited connectivity. But for most ordinary individuals, their communication channels are cut-off.
Though Iran's situation is hardly a new advent, it reminds me that
more and more countries seem to be going for the centralized
filter/control/kill option and what a sad development that is. It sure
seems like this is going to vastly change how inter-nation traffic (or
at least inter-continental) is exchanged between providers and even
how bandwidth is sold. It feels to me like it won't be too much longer
before such things start to become somewhat less a matter of business
and more a matter of treaty.
-Wayne
Digging a little deeper, it looks like Iran's blocking is more complex than I've seen before.
Consumer/mobile networks appear nearly completely blocked.
However, many important business/financial networks and B2B traffic appear operating normally.
I don't yet have good data about of the granularity of the blocking. But the Iranian government is not using the typical blunt cut-off of everything we've seen in other countries.
The vast majority of Iranian ISPs’ international transit connectivity is through AS12880 DCI , which is a government run telecom authority. Google “AS12880 DCI Iran” for more info. DCI is also responsible for layer 2 transport and DWDM services for smaller downstream ISPs, on other international terrestrial fiber links, which are opaque to us NANOG list people from the perspective of global v4/v6 routing table/prefix announcement analysis.
I'm curious to see if there will be a Telecomix grass roots type
resurgence to POTS.