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IP Address Public Policy

IP Address Public Policy

IP addresses are allocated and/or assigned to NTT Singapore Pte Ltd (“NTT Singapore”) from the Regional Internet Registries (“RIRs”) such as APNIC. In turn, NTT Singapore assigns those IP addresses to our customers for use while connected to the NTT Singapore network. The size of the IP address assignment varies and is solely based on the continually demonstrated and documented need of the customer.

Table of Contents

  1. Introduction
  2. Guidelines for Customers
  3. Documentation Required
  4. IP Address Justification (IPJ) Forms

I. Introduction

The NTT Singapore IP Address Policy (“this Policy”) has been created with guidance from various Request For Comments documents (“RFCs”) and the existing policies of the RIRs from which NTT Singapore obtains IP addresses which are for the time being in force (collectively the “IP Policies”). This Policy is also subject to the IP Policies. In the event of any conflict or inconsistencies between the terms/guidelines set out in this Policy and the IP Policies, the terms/guidelines set out in the IP Policies shall prevail to the extent permitted by the applicable law.

NTT Singapore reserves the right to change, amend or vary this Policy at any time in its sole and absolute discretion without prior notice to its customers. Kindly refer to NTT Singapore’s website for the latest version of this Policy. The latest version of this Policy will supersede all the previous versions.

Customer shall not sell, resell, dispose of, provide, transfer, assign, sub-assign, license or sub-license the IP Address space assigned to customer by NTT Singapore.

NTT Singapore assigns IP addresses with three goals in mind:

  1. Conservation: The objective distribution of globally unique IP address space according to the operational needs of customers. NTT Singapore tries to prevent stockpiling in order to maximize the utilization of IP address space.
  2. Routability: The distribution of globally unique IP address space in a hierarchical manner, which permits scalability in the internet routing table. The assignment of IP address space by NTT Singapore does not guarantee routability, due to other ISPs routing policies.
  3. Registration: NTT Singapore is required by APNIC to provide information on which entity is using the IP space. This information can be provided to APNIC either via a RWhois server. NTT Singapore documents the assignment of IP addresses to a customer via a publicly available Referral WHOIS (rwhois) server. If a customer is assigned static IP addresses, the customer information will be added to the RWhois server. This information includes: customer's name, company name if a business, postal address, e-mail address, IP address, and telephone number.

NTT Singapore realizes that conservation and routability can be conflicting goals. NTT Singapore will review individual cases when there are conflicts to try to work out an appropriate compromise.

II. Guidelines for Customers

NTT Singapore has developed the following guidelines that will be applied to customer’s requests for IP address space:

  1. IP addresses are assigned in blocks that conform to Classless Inter-Domain Routing (“CIDR”) boundaries. Customers should use classless technologies and routing protocols that support variable length subnet mask (“VLSM”).
  2. IP addresses are assigned for the duration of the customer's connection to the NTT Singapore network and must be routed to the NTT Singapore network. In the event that the customer disconnects from the NTT Singapore network or stops routing the addresses to the NTT Singapore network, a 30 day grace period will be given for the customer to renumber out of their assigned IP address space.
  3. At no time shall a current NTT Singapore customer use and/or announce NTT Singapore IP addresses that have not been specifically assigned to them. Former NTT Singapore customers and non-customers may not use and/or announce any NTT Singapore IP addresses except in cases where a formal agreement has been reached (e.g. BGP multihoming). Unauthorized use and/or announcement of NTT Singapore IP addresses will result in NTT Singapore  immediately reclaiming the unauthorized IP addresses and this may jeopardize current and future IP address assignment from NTT Singapore to such customer.
  4. In the event that a NTT Singapore customer (“Customer A”) acquires/merges/takes over another NTT Singapore customer (“Customer B”), the resulting customer on record will be required to renumber "Customer B" into IP address space assigned to "Customer A". Should the resulting customer require additional space to accommodate this renumbering, they will need to complete an IP Address Justification (IPJ) form (documenting their address space utilization) for review and approval by NTT Singapore.
  5. At any time, NTT Singapore may require a customer to justify its IP address assignment. If the customer is unable to do so, its ability to obtain future assignments may be jeopardized and its existing assignment may be revoked.
  6. IP addresses are assigned to customers using a "slow-start" process. New customers will receive a minimal assignment based on their immediate requirement. Thereafter, the size of the assigned IP address blocks may be increased based on the speed that the customer utilizes all previously assigned IP address blocks.
  7. RIRs may set a maximum size of the IP address assignment that NTT Singapore is allowed to make. If a customer requests an assignment size that is above the RIR size limit, the RIR reserves the right to review and approve the assignment. The RIR may have different guidelines than NTT Singapore does for reviewing and approving the assignment and the customer would be required to adhere to the RIR's guidelines.
  8. Due to the limited availability of IP (v4) address space, the practice of assigning a unique IP address per dialup user is discouraged.
  9. The Internet community filters IPV6 announcements based on the IPV6 allocations from APNIC / RIPE. The allocations (and filtering) are necessary in order to minimize routing table expansion. Any customer requiring BGP multi-homing, now or in the future, should apply for Provider Independent (PI) IPv6 space directly from APNIC / RIPE. APNIC / RIPE can also allocate /48 critical infrastructure space if justified (eg. root domain operators). Customers with multiple connections to the NTT Singapore network may announce longer prefixes along with their APNIC / RIPE allocation to effectively manage their inbound traffic, but the longer prefixes will not be propagated beyond the AS2914 /or  AS17645 backbone.
    More information regarding APNIC / RIPE 's IPv6 assignment and allocation policies can be found here:
  10. When a customer requests an IP address space assignment from NTT Singapore that will be used for IP-based web hosting, the customer will need to provide technical justification as to why they are providing IP-based web hosting instead of name-based web hosting. NTT Singapore is required to provide this information to the RIRs.

III. Documentation Required

Before NTT Singapore makes an IP address assignment to a customer, the following documentation must be submitted by the customer. NTT Singapore will not begin the IP address assignment process until all of the required documentation has been submitted. A link to the NTT Singapore IP Address Justification form is included in section IV.

  1. Documentation of existing IP address space usage. This shows how any space the customer has is currently being used, along with projections for the next 3 and 6 months.
  2. Documentation showing how the requested IP space will be used. This shows how the customer plans to use the space immediately, along with projections for the next 3 and 6 months.
  3. A network topology map for all requests of 32 IP addresses (/27) or larger.
  4. A description of the network routing plans, along with any protocols used and the protocol limitations.
  5. For customers requesting space for web hosting, a list of IP addresses currently being used for web hosting, and a list of domains being hosted. If IP-based hosting is being done, a list of technical reasons why named-based hosting cannot be done must be included.

This information will be used by NTT Singapore ONLY to justify the assignment of IP addresses to a customer. The information may also be given to the RIRs if they request it as part of reviewing their assignments to NTT Singapore.

IV. IP Address Justification (IPJ) Forms

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