Temporarily the service desk by phone is suspended due to Coronavirus (COVID-19).
If you have any questions, please contact us via an email.

Inquiries about subscribing, connecting, and other services

Academic Infrastructure Division, SINET team

  • e-mail: apply[@]
  • TEL: 03-4212-2265 / FAX: 03-4212-2270 [G3]
  • Hours: 9:00-17:00(Mon-Fri)

Applications / inquiries sent on weekends/holidays will be handled on the next working day
or thereafter.


  • Inquiries about subscribing a/o connecting to SINET
  • Inquiries about application procedures for SINET services
  • Disclosure of information for connecting to a SINET node
  • Inquiries about accessing to a SINET node rack(for cable installation etc.)

Inquiries / reports about communication faults

SINET Operation Center

  • e-mail: ipnoc[@]
  • TEL: 03-3263-5804
  • Hours: 24×365(incl. nighttime and holidays)


  • Accepts SINET fault reporting
  • Investigates a/o copes with SINET faults
  • Handles SINET equipments configuration for subscribers’ SINET connections
  • Accepts starting/ending calls on SINET node rack access
  • Accepts emergency SINET node rack access requests

Inquiries / consultation requests about network design, user organization support

Academic Infrastructure Division, SINET Promotion Office

  • e-mail: support[@]
  • TEL: 03-4212-2269 / FAX: 03-4212-2270 [G3]
  • Hours: 10:00-16:00(Mon-Fri)

Inquiries / consulting requests sent on weekends/holidays will be handled on the next working day
or thereafter.


  • User consultation/response
  • Technology promotion and educational campaign (lectures and technological exchanges)
  • Troubleshooting support of performance-related problems
  • Interviews/surveys on user requests

Inquiries on services related to SINET node datacenter premises

Inquiries related to connecting to SINET should be go to Academic Infrastructure Division, SINET team.

NTT East, Data Center Help Desk

  • e-mail: sinet6-dc-ml[@]


  • Inquiries related to in-house wiring for connecting to SINET
  • Inquiries related to rack housing service in the same datacenter premise as SINET node