Subj : Re: Birthday present from he.net (some birthday)
To   : Michiel van der Vlist
From : Tony Langdon
Date : Mon Jul 11 2016 10:24:00

-=> Michiel van der Vlist wrote to Tony Langdon <=-

 MvV> Hello Tony,

 MvV> On Monday July 11 2016 07:35, you wrote to Joe Delahaye:


 TL> Interesting.  But I do know multiple global IPv6 addresses per
 TL> interface is pretty common.

 MvV> This is one of the big differences between IPv4 and IPv6. Although it
 MvV> is possible to assign more than one Ip addres to an interface, it is
 MvV> far from common, Normally an interface has just one IP address. In IPv6

Unless you're like me, where I have several IPv4 interfaces with multiple IP
addresses - a VPS with 14 IPs and 3 or 4 machines here with at least 2 IPs on
the one interface, sue to multiple networks here.  But yes, for most people,
multiple IPv4 addresses on the one interface is not common.

 MvV> one has at least two IP adresses. There is always the link local
 MvV> address that starts with fe80::. The lower 64 bits are derived from tha
 MvV> MAC address of the interface. To translate the 48 bit MAC address to

 MvV> For a server you want to advertise an address that is as stable as
 MvV> possible. That means either a manually static address or a SLAAC
 MvV> address. They only change when the ISP changes the prefix. Which if you
 MvV> are lucky never or rarely happens.

I use static IPs here for my servers, because that way I can choose a host
address that's easy to remember within my prefix.  For the most part, I've been
making the host part of mt static IPv6 addresses the same (in hex) as the host
part of the (private) IPv4 address.  If you look carefully, you'll see that on
this host. :)


Ethernet adapter Local Area Connection:

   Connection-specific DNS Suffix  . :
   IPv6 Address. . . . . . . . . . . : 2001:44b8:4176:f100::19                 
          <-- 19 in hex = 25 in decimal
   IPv6 Address. . . . . . . . . . . : 2001:44b8:4176:f100:a93d:90f3:6746:7f73
   Temporary IPv6 Address. . . . . . : 2001:44b8:4176:f100:49bd:331c:d2f6:35c1
   Link-local IPv6 Address . . . . . : fe80::a93d:90f3:6746:7f73%11
   IPv4 Address. . . . . . . . . . . : 10.69.181.25                            
          <-- 25 in decimal = 19 in hex
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : fe80::9ec7:a6ff:fe25:4d9b%11
                                       10.69.181.1
.... Brain: the apparatus with which we think we think
--- MultiMail/Win32 v0.49
 * Origin: Freeway BBS - freeway.apana.org.au (3:633/410)

.