STEP 1: Firstly, you need to go to my.itldc.com.
STEP 2: Select a service.
STEP 3: Click on “IP-addresses“.
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STEP 4: Click the “Order” button.
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STEP 5: Select IPv4 or IPv6.
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STEP 6: Set the number of IP-addresses that you want to order and click on “Reboot server” checkbox to apply changes.
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STEP 7: Click the “To shopping cart” button.
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STEP 8: To pay, click the “Pay” button and follow the steps on the payment page.
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STEP 9: You need to configure your network setting in your OS to use new addresses.
NOTE: To set up by your own, you can read these tutorials: