This is the situation on the next day after the quake struck. 3/12 (Sat) around noon, according to my friend Asako Itagaki at WirelessWire News
Source: WirelessWire News 3/12 noon
NTT East (local telephone in the eastern Japan)
- Service interruption: 485,000 analog telephone lines, 79,500 ISDN and Flet's ISDN, 208,600 Flet's Hikari (FTTH), mainly in Miyagi and Iwate prefectures
- In all NTT East area (east of Niigata, Nagano, Yamanashi and Kanagawa, total of 17 prefectures), public phone are open to public for free
NTT Communications (long distance)
- Approx. 500 enterprise lines (Arcstar Direct) are disrupted mainly in Tohoku Area
- OCN (ISP) is unstable in Tohoku Area (Miyagi, Iwate, Fukushima, Akita and Yamagata)
- Approx. 12000 enterprise data service lines (IP-VPN、e-VLAN etc.) are unstable in some parts of Tohoku Area
KDDI
- Some of analog telephone lines are unstable
- Internet service such as au one net, IP-VPN, WVS, Ether VPN, Hikari Direct, Metal Plus, IP Phone, Cable Plus Phone are unstable in some parts of the affected area, Hokkaido, Aomori, Iwate, Akita, Miyagi, Yamagata and Fukushima prefectures
Softbank Telecom
- Some telecom services are unstable in the affected area, Aomori, Iwate, Akita, Miyagi, Yamagata, Fukushima and Ibaragi prefectures
Michi