SOLVED: What Are The Loopback Addresses in IPv6 IPv4 and What Are All The Other Special Use IP Ranges?

If you are working on a network you are going to see some IPv6 traffic and it can get quite confusing.  A “loopback” is an address that causes the traffic to be sent to the same interface is was sent out on on the localhost.

what-is-loopback-ipv4-ipv6-test-network-cardUsage of loopback addresses are particularly popular with developers and anyone in IT performing network tests.  For instance, if you think your Network Card is failing you can try:

PING 127.0.0.1

and if you don’t see a reply with a TIME<1ms, your card or TCP/IP stack likely has a problem.  If you are on a PC that supports IPv6 (all Windows 10, 8, 7 and Vista PC’s), you can try the same test using:

PING ::1

Below are all of the loopback IP addresses:

  • IPv6 = 0:0:0:0:0:0:0:1
  • IPv6 = 0:0:0:0:0:0:0:0
  • IPv6 = 0:0:0:0:0:ffff:7f00:1
  • IPv6 = ::1
  • IPv6 = ::
    .
    .
  • IPv4 = 127.0.0.1 to 127.255.255.255

Below is a table of all the ‘Special Use’ IP Ranges:

0.0.0.0/8             “This” Network

10.0.0.0/8            Private-Use Networks

14.0.0.0/8            Public-Data Networks

24.0.0.0/8            Cable Television Networks

39.0.0.0/8            Reserved, subject to allocation

127.0.0.0/8          Loopback

128.0.0.0/16        Reserved, subject to allocation

169.254.0.0/16    Link Local

172.16.0.0/12      Private-Use Networks

191.255.0.0/16    Reserved, subject to allocation

192.0.0.0/24        Reserved but subject to allocation

192.0.2.0/24        Test-Net

192.88.99.0/24    6to4 Relay Anycast

192.168.0.0/16    Private-Use Networks

198.18.0.0/15        Network Interconnect Device Benchmark Testing

223.255.255.0/24     Reserved, subject to allocation

224.0.0.0/4          Multicast, commonly used in multiplayer simulations and gaming and for video distribution.

240.0.0.0/4          Reserved for Future Use

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Questions or Comments?