Loopback 2 1 34
In the Internet addressing architecture, the Internet Engineering Task Force (IETF) and the Internet Assigned Numbers Authority (IANA) have reserved various Internet Protocol (IP) addresses for special purposes.[1]
IPv4[edit]
IPv4 designates special usage or applications for various addresses or address blocks: [1][2]
| Address block | Address range | Number of addresses | Scope | Description |
|---|---|---|---|---|
| 0.0.0.0/8 | 0.0.0.0–0.255.255.255 | 16777216 | Software | Current network[3] (only valid as source address). |
| 10.0.0.0/8 | 10.0.0.0–10.255.255.255 | 16777216 | Private network | Used for local communications within a private network.[4] |
| 100.64.0.0/10 | 100.64.0.0–100.127.255.255 | 4194304 | Private network | Shared address space[5] for communications between a service provider and its subscribers when using a carrier-grade NAT. |
| 127.0.0.0/8 | 127.0.0.0–127.255.255.255 | 16777216 | Host | Used for loopback addresses to the local host.[3] |
| 169.254.0.0/16 | 169.254.0.0–169.254.255.255 | 65536 | Subnet | Used for link-local addresses[6] between two hosts on a single link when no IP address is otherwise specified, such as would have normally been retrieved from a DHCP server. |
| 172.16.0.0/12 | 172.16.0.0–172.31.255.255 | 1048576 | Private network | Used for local communications within a private network.[4] |
| 192.0.0.0/24 | 192.0.0.0–192.0.0.255 | 256 | Private network | IETF Protocol Assignments.[3] |
| 192.0.2.0/24 | 192.0.2.0–192.0.2.255 | 256 | Documentation | Assigned as TEST-NET-1, documentation and examples.[7] |
| 192.88.99.0/24 | 192.88.99.0–192.88.99.255 | 256 | Internet | Reserved.[8] Formerly used for IPv6 to IPv4 relay[9] (included IPv6 address block 2002::/16). |
| 192.168.0.0/16 | 192.168.0.0–192.168.255.255 | 65536 | Private network | Used for local communications within a private network.[4] |
| 198.18.0.0/15 | 198.18.0.0–198.19.255.255 | 131072 | Private network | Used for benchmark testing of inter-network communications between two separate subnets.[10] |
| 198.51.100.0/24 | 198.51.100.0–198.51.100.255 | 256 | Documentation | Assigned as TEST-NET-2, documentation and examples.[7] |
| 203.0.113.0/24 | 203.0.113.0–203.0.113.255 | 256 | Documentation | Assigned as TEST-NET-3, documentation and examples.[7] |
| 224.0.0.0/4 | 224.0.0.0–239.255.255.255 | 268435456 | Internet | In use for IP multicast.[11] (Former Class D network). |
| 240.0.0.0/4 | 240.0.0.0–255.255.255.254 | 268435455 | Internet | Reserved for future use.[12] (Former Class E network). |
| 255.255.255.255/32 | 255.255.255.255 | 1 | Subnet | Reserved for the 'limited broadcast' destination address.[3][13] |
IPv6[edit]

Loopback 2.1.4 Released March 24, 2020 (Release Notes) For MacOS 10.12 or higher. What People Are Saying About Loopback. Recipient of a near-perfect 4.5/5 mice from. 7–2 Altera Corporation Stratix GX Device Handbook, Volume 2 June 2006 Parallel Loopback Figure 7–1. Stratix GX Block in Serial Loopback Mode Parallel Loopback Figure 7–2 shows the data path for parallel loopback. A data stream is fed to the transmitter from the FPGA logi c array and has the option of using blocks in the transmitter block. $ nc -l -p 10001 fe80::1%lo $ nc fe80::1%lo 10001 Verifying correct scope: $ ip -6 a 1: lo: LOOPBACK,UP,LOWERUP mtu 65536 inet6 fe80::1/64 scope link validlft forever preferredlft forever Still it seems not very elegant having to add every single IP to be able to bind to it.
Method 2 To install the Microsoft Loopback Adapter by using the Hardware Wizard, follow these steps: In Control Panel, double-click Add Hardware, and then click Next; Click Yes, I have already connected the hardware, and then click Next. At the bottom of the Installed hardware list, click Add a new hardware device, and then click Next. LoopBack 2: End-of-Life: Jul 2014: Apr 2019: Learn more about our LTS plan in docs. 2.38.1 (LTS) Latest Mar 13, 2017 + 174 releases Packages 0.

IPv6 assigns special uses or applications for various IP addresses:[1]
| Address block (CIDR) | First address | Last address | Number of addresses | Usage | Purpose |
|---|---|---|---|---|---|
| ::/0 | :: | ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff | 2128 | Routing | Default route (no specific route) |
| ::/128 | :: | :: | 1 | Software | Unspecified address. |
| ::1/128 | ::1 | ::1 | 1 | Host | Loopback address to the local host. |
| ::ffff:0:0/96 | ::ffff:0.0.0.0 | ::ffff:255.255.255.255 | 2128−96 = 232 = 4294967296 | Software | IPv4 mapped addresses. |
| ::ffff:0:0:0/96 | ::ffff:0:0.0.0.0 | ::ffff:0:255.255.255.255 | 232 | Software | IPv4 translated addresses. |
| 64:ff9b::/96 | 64:ff9b::0.0.0.0 | 64:ff9b::255.255.255.255 | 232 | Global Internet | IPv4/IPv6 translation.[14] |
| 100::/64 | 100:: | 100::ffff:ffff:ffff:ffff | 264 | Routing | Discard prefix.[15] |
| 2001::/32 | 2001:: | 2001::ffff:ffff:ffff:ffff:ffff:ffff | 296 | Global Internet | Teredo tunneling. |
| 2001:20::/28 | 2001:20:: | 2001:2f:ffff:ffff:ffff:ffff:ffff:ffff | 2100 | Software | ORCHIDv2.[16] |
| 2001:db8::/32 | 2001:db8:: | 2001:db8:ffff:ffff:ffff:ffff:ffff:ffff | 296 | Documentation | Addresses used in documentation and example source code.[17] |
| 2002::/16 | 2002:: | 2002:ffff:ffff:ffff:ffff:ffff:ffff:ffff | 2112 | Global Internet | The 6to4 addressing scheme (now deprecated).[8] |
| fc00::/7 | fc00:: | fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff | 2121 | Private network | Unique local address.[18] |
| fe80::/10 | fe80:: | febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff | 2118 | Link | Link-local address. |
| ff00::/8 | ff00:: | ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff | 2120 | Global Internet | Multicast address. |
See also[edit]
- Classless Inter-Domain Routing (CIDR)
References[edit]
Loopback /32
- ^ abcM. Cotton; L. Vegoda; R. Bonica; B. Haberman (April 2013). Special-Purpose IP Address Registries. Internet Engineering Task Force. doi:10.17487/RFC6890. BCP 153. RFC6890. Updated by RFC 8190.
- ^https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml
- ^ abcdM. Cotton; L. Vegoda; R. Bonica; B. Haberman (April 2013). Special-Purpose IP Address Registries. Internet Engineering Task Force. doi:10.17487/RFC6890. BCP 153. RFC6890. Updated by RFC 8190.
- ^ abcY. Rekhter; B. Moskowitz; D. Karrenberg; G. J. de Groot; E. Lear (February 1996). Address Allocation for Private Internets. Network Working Group. doi:10.17487/RFC1918. BCP 5. RFC1918. Updated by RFC 6761.
- ^J. Weil; V. Kuarsingh; C. Donley; C. Liljenstolpe; M. Azinger (April 2012). IANA-Reserved IPv4 Prefix for Shared Address Space. Internet Engineering Task Force (IETF). doi:10.17487/RFC6598. ISSN2070-1721. BCP 153. RFC6598.
- ^S. Cheshire; B. Aboba; E. Guttman (May 2005). Dynamic Configuration of IPv4 Link-Local Addresses. Network Working Group. doi:10.17487/RFC3927. RFC3927.
- ^ abcJ. Arkko; M. Cotton; L. Vegoda (January 2010). IPv4 Address Blocks Reserved for Documentation. Internet Engineering Task Force. doi:10.17487/RFC5737. ISSN2070-1721. RFC5737.
- ^ abO. Troan (May 2015). B. Carpenter (ed.). Deprecating the Anycast Prefix for 6to4 Relay Routers. Internet Engineering Task Force. doi:10.17487/RFC7526. BCP 196. RFC7526.
- ^C. Huitema (June 2001). An Anycast Prefix for 6to4 Relay Routers. Network Working Group. doi:10.17487/RFC3068. RFC3068. Obsoleted by RFC 7526.
- ^S. Bradner; J. McQuaid (March 1999). Benchmarking Methodology for Network Interconnect Devices. Network Working Group. doi:10.17487/RFC2544. RFC2544. Updated by: RFC 6201 and RFC 6815.
- ^M. Cotton; L. Vegoda; D. Meyer (March 2010). IANA Guidelines for IPv4 Multicast Address Assignments. Internet Engineering Task Force. doi:10.17487/RFC5771. BCP 51. RFC5771.
- ^J. Reynolds, ed. (January 2002). Assigned Numbers: RFC 1700 is Replaced by an On-line Database. Network Working Group. doi:10.17487/RFC3232. RFC3232. Obsoletes RFC 1700.
- ^Jeffrey Mogul (October 1984). Broadcasting Internet Datagrams. Network Working Group. doi:10.17487/RFC0919. RFC919.
- ^C. Bao; C. Huitema; M. Bagnulo; M. Boucadair; X. Li (October 2010). IPv6 Addressing of IPv4/IPv6 Translators. Internet Engineering Task Force. doi:10.17487/RFC6052. RFC6052.
- ^N. Hilliard; D. Freedman (August 2012). A Discard Prefix for IPv6. Internet Engineering Task Force. doi:10.17487/RFC6666. RFC6666.
- ^J. Laganier; F. Dupont (September 2014). An IPv6 Prefix for Overlay Routable Cryptographic Hash Identifiers Version 2 (ORCHIDv2). Internet Engineering Task Force. doi:10.17487/RFC7343. RFC7343.
- ^G. Huston; A. Lord; P. Smith (July 2004). IPv6 Address Prefix Reserved for Documentation. Network Working Group. doi:10.17487/RFC3849. RFC3849.
- ^R. Hinden; B. Haberman (October 2005). Unique Local IPv6 Unicast Addresses. Network Working Group. doi:10.17487/RFC4193. RFC4193.