IP Addressing Policy

 

Introduction and Overview

IPv4 IP address space is a limited resource that is being depleted at a significant rate. Five Regional Registries have been established around the world to regulate the usage of these addresses. These registries are governed by the Internet Community. In the United States, we are governed by the American Registry for Internet Numbers (ARIN).

The minimum direct allocation ARIN can provide is a /20 for single homed companies, and a /22 for multihomed companies. Most companies need to contact their upstream provider, in this case tw telecom, to obtain IP Address space. In order for tw telecom to acquire address space from ARIN, we must follow their guidelines for IP address assignments and allocations and must enforce efficient utilization of IP addresses. This means that our customers must justify their IP needs to us in detail and according to ARIN's guidelines for effective usage.

ARIN's policies can be found on their website. Links to the ARIN website are at the bottom of the page.

All information disclosed to tw telecom during this process is confidential, with a single exception. We are required to provide ARIN with the same information you provide to us in order to justify our need for additional address space.

All numbers must be accounted for, and each address block must be reassigned via SWIP, RWHOIS or internal databases. At this time, tw telecom uses an RWHOIS server for most assignments. SWIP is available when necessary. Large address consumers will also be required to maintain, and provide upon request, a database of how addresses are assigned internally.



Guidelines and Rules

  • tw telecom typically will not provide aggregate allocations larger than a /20. Applications for address allocations larger than a /20 may be directed to ARIN.

  • tw telecom typically will not provide allocations or assignments to customers who already have a direct allocation from ARIN.

  • A usage figure of 80 percent must be achieved within 90 days after allocation/assignment, or the addresses will be withdrawn. (Eighty percent usage is based on SWIP records and a simple ICMP scan run against all assigned net blocks.)

  • Customers must maintain proper reverse DNS records for all assigned or allocated addresses. Contact hostmaster@twtelecom.net with any questions.

  • Customers will not be given address space for administrative convenience.

  • tw telecom cannot guarantee the assignment of contiguous netblocks.

  • We reserve right to change customer assignments/allocations as necessary.

ARIN Links
    ARIN - Official Website
    Official ARIN Policies