Virginia Tech IP Addresses

As part of the regular security configuration of various information resources at Virginia Tech, system administrators sometimes want to restrict access to certain services to what are commonly referred to as "Virginia Tech" hosts. There is often considerable confusion about what this means as well as which addresses should be covered in this matter. Following is information you need to know before restricting access to any of the addresses listed below.

Contents

• Introduction
• Addresses
• Contact Information

Introduction

It is imperative to note that any network traffic with source address matching one of the below addresses does not guarantee that the originator of the traffic is either affiliated with Virginia Tech or on the Virginia Tech campus. The reasons for this are varied, but include:

• the relatively open access of certain network portals on campus
• the ability for people on the Virginia Tech campus to proxy connections (willingly or otherwise) for off-campus connections
• agreements with off-campus network providers to use Virginia Tech as a means of Internet access for their Virginia Tech affiliated customers

Additionally, there are many Virginia Tech affiliates, including those who are resident at remote sites (e.g. Northern Virginia) or who have an alternative ISP, who may be inappropriately excluded from those services which use source IP address as a method of access control.

It must be recognized, therefore, that restricting access on the basis of source IP address is seldom a worthwhile security measure for services that should be available to a large portion of the Virginia Tech community. It does not accurately specify that the person of said source address is or is not a Virginia Tech affiliate, nor does access control based on IP address obviate the need for user-level access control.

A more serious concern is the management of the networks involved. On networks managed by CNS (Communications Network Services), it is reasonably safe to say that if there is misconduct from a network user, calling 4Help will likely curtail the problem. This may or not be the case for other networks.

CNS offers a remote access service that includes a Virtual Private Network (VPN) so that you can have an "on-campus" address no matter where you are. For more information, see Virtual Private Network (http://www.computing.vt.edu/internet_and_web/internet_access/vpn.html).

Addresses

Following are the IP addresses for the Virginia Tech community. These data are in network address/network mask length format. For help with deciphering this format, refer to Wikipedia's IPv4 Subnetting Reference.

While best effort is made to maintain the information on this page, these data are not guaranteed to be up-to-date.

Contact Information

Communications Network Services (CNS)

• The routers managed by CNS are configured in accordance with best-practice methods to ensure that traffic with source addresses that should be on-campus do not enter the campus from outside and vice-versa.
• When arranging with off-campus providers, these providers may not issue a "Virginia Tech IP address" to non-Virginia Tech affiliates.

National Capital Region (NCR)

Richmond Center (RC)

Extension (EXT)

VTACS (VTACS)

Center for European Studies and Architecture (CESA)

Applied Research Laboratory for National & Homeland Security (HNS)

ARIN Whois

You may also be able to find contact information for these sites using ARIN's Whois search found at http://www.arin.net.