On 22. feb. 2011, at 16.22, Joachim Schipper wrote: > On Tue, Feb 22, 2011 at 03:04:25PM +0100, Pete Vickers wrote: >> Now that the IPv4 address space if fully allocated, perhaps it's time to >> update the comments in /etc/hosts ? Here is my attempt at a reasonably concise >> update: >> >> # Assignments from RFC5735 (supersedes RFC1918) >> # >> # Allocated for use as the Internet host loopback address: >> # 127.0.0.0/8 >> # >> # Allocated for communication between hosts on a single link. Hosts obtain >> # these addresses by auto-configuration (in the absence of DHCP): >> # 169.254.0.0/16 >> # >> # Addresses within these blocks do not legitimately appear on the public >> Internet >> # and can be used without any coordination with IANA or an Internet registry: >> # 10.0.0.0/8 private networks >> # 172.16.0.0/12 private networks >> # 192.168.0.0/16 private networks >> # 192.0.2.0/24 documentation/examples >> # 198.51.100.0/24 documentation/examples >> # 203.0.113.0/24 documentation/examples >> # 198.18.0.0/15 benchmark interconnect testing >> # >> # Full assignments details are available here: >> # http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.txt >> # >> >> >> >> More contentiously, this is an IPv6 counterpart: > >> Note that I interpret the aim of these comments as an aide-memoire, rather >> than a tutorial on IP addressing schemes, so it's intentionally brief. > > I think your IPv4 text unwisely suggests that using e.g. 192.0.2.0/24 > for your own stuff is okay. That's true only until you put a device with > an appropriate list of "unroutable IPs" on your network, etc.
All those prefixes are 'unroutable' on the public Internet, and 'routable' on private internetworks at the admin's discretion. 192.0.2.0/24 is no different to the other addresses: RFC5735 says "... do not legitimately appear on the public Internet and can be used without any coordination with IANA or an Internet registry". > > Also, if you're going to be exhaustive, you missed at least multicast. hence my comment about being intentionally brief. > > Why do you feel this is useful? It appears to me that the existing 'listing' is half complete, so I proposed a more through version, obviously another alternative would be to remove these bits altogether: # RFC 1918 specifies that these networks are "internal". # 10.0.0.0 10.255.255.255 # 172.16.0.0 172.31.255.255 # 192.168.0.0 192.168.255.255 > > Joachim > /Pete Pete Vickers p...@systemnet.no | +47 48 17 91 00 SystemNet AS
