HomeSubnet Configuration Guide

Subnet Subnet Configuration Guide

1. Configuring Subnets under the University LAN

To configure subnets under the University LAN, you must adhere to the networking rules to ensure sound network usage for all other users within and outside the University, and prevent network problems and failures. Address such problems and failures immediately should they occur.

1.1 The Role of the Information and Media Center (IMC)

- IMC assigns subnet addresses.

- IMC creates and saves the pan-University subnet address database.

1.2 The Role of a Subnet Administrator in Each Department or Center

- The subnet administrator assigns IP addresses to devices within the subnet at the request of users in the department.

1.3 Duty of a Subnet Administrator

- Share the subnet information with the IMC. Subnet registration must be updated at the fiscal year end.

- Registering and Starting the DNS Server

The subnet must be administered independently. In other words, the primary DNS server (both forward and reverse lookup) must be configured in the subnet.
If you are unable to configure the primary DNS server within the subnet, request an appropriate party to perform the configuration. Also, request an appropriate party (usually the departmental subnet administrator) to configure the secondary DNS server in the forward lookup zone.
If no one is available to help you, the IMC can configure the secondary DNS server in the forward lookup zone.
The secondary DNS server in the reverse lookup zone will always be configured by the IMC for any subnet. The DNS server can also be configured using the IMC’s hosting service.

- Joining the DNS Server Administrator Mailing List

The subnet administrator must join the mailing list ( to receive communications between DNS server administrators.

To join this mailing list, register yourself with the subnet administrator mailing list of the department.

2. Administrative Procedures

- Read the respective application manual for the above administration procedures.

- Updating subnet registration

The subnet connected to the University LAN must be registered and its registration must be updated at the fiscal year end. The IMC distributes Subnet Connection Application Forms to each applicant. Check the details of the subnet described in your form and correct as necessary before returning the form to the IMC.

Also, submit the list of devices connected to the subnet by the specified deadline.

- If you change the details in the Subnet Connection Application Form or cancel the connection, submit the Form as soon as possible to the IMC.

3. References

- 3.1 Subnet Mask Setting

The current netmask is 8 bit. Following the instructions for each device, set the netmask of the device to 0xffffff80 or

3.2 Default Route Setting

Following the instructions for each device, set the default route of the device to the subnet gateway.