Chapter 23. summary of tcp/ip networking
After speaking a great deal about addressing in IPv6, anybody still
here will hope that you have a correct way to abstract all
these lengthy & ugly IPv6 addresses with a few nice hostnames
as you can perform in IPv4, not to mention there’s.
Hostname to Ip resolving in IPv4 is generally completed in
1 of 3 ways: utilizing a simple table in
while using Network Information Service (NIS, formerly YP)
or through the Website Name System (DNS).
At this moment, NIS/NIS+ over IPv6 is presently only
on Solaris 8, for database contents and
transport, utilizing a RPC extension.
Getting an easy addressname map like
supported in most IPv6 stacks. Using the KAME implementation
utilized in NetBSD, /etc/hosts contains
in addition to IPv4 addresses. An easy example may be the
“localhost” entry within the default NetBSD installation:
For DNS, there aren’t any essentially new concepts. IPv6
name resolving is performed with AAAA records that – because the
name implies – indicate a business that’s four occasions the
size a b record. The AAAA record requires a hostname on
the left side, just like A does, as well as on the best side
likely to IPv6 address, e.g.
noon IN AAAA 3ffe:400:430:2:240:95ff:fe40:4385
For reverse resolving, IPv4 uses the in-addr.arpa zone,
and below it writes the bytes (in decimal) in
reversed order, i.e. higher bytes tend to be more
right. For IPv6 this really is similar, that hex digits
representing 4 bits are utilized rather of decimal figures,
and also the resource records will also be within different
So to achieve the reverse resolving for that above host, you
would put in your /etc/named.conf
something similar to:
as well as in the zone file db.reverse you place (aside from the usual
records like SOA and NS):
188.8.131.52..4.e.f.f.f.5.9..4.2..2… IN PTR noon.ipv6.example.com.
The address is reversed here, and written lower one hex
digit following the other, beginning using the least significant
(rightmost) one, separating the hex digits with dots, as
usual in zone files.
One factor to notice when establishing DNS for IPv6 would be to take
proper care of the DNS software version being used. BIND 8.x does
understand AAAA records, but it doesn’t offer name
resolving via IPv6. You’ll need BIND 9.x for your. Beyond
that, BIND 9.x supports numerous resource records that
are presently being discussed although not formally
introduced yet. Probably the most noticeable one this is actually the A6
record which enables simpler provider/prefix altering.
To summarize, this spoken concerning the technical
variations between IPv4 and IPv6 for addressing and name
resolving. Some details like IP header options, QoS and
flows were deliberately overlooked not to get this to
document more complicated than necessary.