You are here

User Guide on International Voice/Video Call Service via NRENum.net

  1. Introduction
  2. Who is eligible for this service?
  3. Who can I call?
  4. How to search a number via the NRENum.net directory?
  5. How to make a call?

1. Introduction

International Voice/Video Call Service via NRENum.net (http://www.nrenum.net) is now available for use.  Users with Cisco IP phone installed in the Main Campus, Centennial Campus, Halls, and other academic and administrative buildings can make and receive free Internet calls to and from other Educational and Research Institutions around the world.

2. Who is eligible for this service?

Registration is not required. Anyone who is using a Cisco IP phone in HKU (with telephone number 3917 xxxx) is eligible for this service.

If you are using a video phone, you can also make video calls to the called party with video communication devices (e.g. a video conferencing system or a video phone).

3. Who can I call?

To search for telephone numbers reachable through NRENum.net, please go to http://crawler.nrenum.net to get the up-to-date NRENum.net directory.

4. How to search a number via the NRENum.net directory?

Example: To check if the Hong Kong telephone number 39172111 is accessible via NRENum.net.

  1. Get the full telephone number to be dialed, including the country code. The number is “852 39172111” .
  2. Access the web page http://crawler.nrenum.net via a browser.

Search NRENum.net directory

  1. Click “+852” for Hong Kong numbers. The link under “+8523” contains 15 numbers. It means that the telephone numbers under 852 3xxxxxxx may be reachable. Other numbers are not reachable via NRENum.net because they are show as "empty".

+852 NRENum.net numbers

  1. Click on “+8523” to further drill down into the list. Similarly, the link under “+85239” contains 15 numbers, meaning that telephone numbers under 852 39xxxxxx may be reachable.

+8523 NRENum.net numbers

  1. Click on “+85239” to further drill down into the list. The link under “+852391” contains a list of reachable prefixes, indicated by “x NAPTRs”. This is the bottommost level, showing that all telephone numbers with prefixes “852 39170”, “85239171”, “85239172”, “85239173”, “85239174”, “85239175”, “85239176”, “85239177”, “85239178”, “85239179” are reachable via NRENum.net.

Thus, the telephone number “85239172111” is reachable via NRENum.net.

+85239 NRENum.net numbers

 

5. How to make a call?

Dial “64” + “Country Code” + “Area code” + “Recipient's Phone Number”.

Example: Making a call to Sydney, Australia with number "62112672".

How to make a call via NRENum.net NRENum.net Prefix Country Code Area Code Recipient's Phone Number
Dialing sequence 64 61 2 62112672

Thus, dial " 64 61 2 62112672” to make the international phone call to Sydney, Australia.

Note: It will take a bit longer (more than 10 seconds) to establish an international call via NRENum.net.