Welcome to the ITFreeTraining video on co-existence of the IPv4 and IPv6 protocols. IPv6 will
one day replace IPv4, but until then, the administrator may be in a situation where
they need to support both protocols. This video will take you through where the process
of changing to the IPv6 protocol is done and what happens when both protocols are used
together.
To start with, I will have a quick look at the major developments and milestones of the
IPv6 protocol to give you an idea where the protocol is as of today. In 1994, work was
initiated for a successor to the IPv4 protocol. The 90’s saw a rapid expansion of the internet
and it was quickly determined that the current IPv4 protocol would not have enough IP Addresses
to support internet growth in the long term.
In 1996 alpha code was added to the Linux kernel. Still considered experimental, but
operating system support was on the way.
In 1998 the Internet Engineering Task Force formally announced IPv6 as the successor to
IPv4. A lot of work had been done before this, but now officially it was announced that this
was the protocol that would one day replace IPv4.
In 2002, Microsoft added IPv6 support to Windows XP. The protocol was effectively bolted onto
the operating system. This gave IPv6 support but since it was an add-on, performance was
not the best.
In 2005 Linux changed its IPv6 support from experimental. This means IPv6 was officially
supported in Linux and is considered to be stable.
Following this, in 2007 Microsoft released Windows Vista and with it IPv6 was completely
redesigned rather than being an add-on in the operating system. It was also made the
default protocol in the operating system, so if IPv6 is available, Windows will use
this over IPv4.
Lastly, in 2008, six of the root name servers had IPv6 quad A records added to them. This
means that IPv6 resolution on the internet is now possible. You can see after 2008 the
operating systems and the internet core DNS services are ready, so what is holding back
IPv6?
If I now have a closer look at the current status of IPv6, it can be seen that OS Support
is pretty much done. Nowadays even devices like Android and IOS support IPv6. Since OS
support has been available for a while now, application support has improved. It is up
to the developer to make sure that their software supports IPv6. It is difficult to get statistics
on current software support; however, a quick look at the feature list of most applications
nowadays will show IPv6 support.
The last point to consider is ISP support. This is where IPv6 adoption has been slow.
To have a look at how slow, let’s have a look at some statistics.
To do this, I will open internet explorer. Once open, I will do a search for “state
of the internet IPv6”. In this case, the first result is the page I want which I will
select. If you have trouble finding this page, I have left a link for it in the references
part of this video.
If I scroll down, this page shows statistics of how many content requests are made using
IPv6. This essentially means an IPv6 client has made a content request using the IPv6
protocol. You can see that at the top is Belgium. Notice this is 41%, so not even the top country
is above 50%.
Following this, notice that the USA is just above 20%. If I scroll down, notice the percentages
quickly reduce. These statistics suggest that world-wide, IPv6 is not being utilized that
much. To understand why, I will go to google and perform a search for “IPv6 measurements”.
The fist result is the page that I am after so I will select it, the link is in the references
section if you cannot find it.
This page gives an indication of how the deployment of IPv6 for different ISPs is progressing.
Notice that Comcast is listed at 40%. Different parts of the Comcast network are IPv6 ready.
This means, if you are connected to Comcast, where you live will determine if you can get
IPv6 or not.
Notice that below this, AT&T is 51%, but “Verizon Wireless” is the highest at 72%. Since wireless
generally uses newer technology. Since wireless was generally deployed later then cable networks,
this may be part of the reason for the higher figure. In a lot of cases, many ISP’s are
behind on IPv6 deployment as they don’t wish to upgrade their existing infrastructure
if it is still doing a good job of running IPv4 networks. So you can see, where you live
and the ISP you are connected to will determine if you can get IPv6 or not.
If I now scroll down, notice the graphic of percentage of websites available via IPv6
is just under 20%. This is one of the issues with IPv6 deployment. To demonstrate this
better, I will open a command prompt and ping google.com.
Notice that the computer contacts google using the IPv6 address. So google is IPv6 ready.
If I ping facebook.com, notice also the IPv6 address is used. A lot of big companies on
the internet have made their sites IPv6 ready.
However, notice that when I ping Microsoft.com, the IPv4 address is used rather than the IPv6
address. Since Windows will default to the IPv6 protocol, when this happens it general
means that the site cannot be contacted using IPv6. The ping command will also not get a
response back from Microsoft. This does not mean the site is down, it may mean that Microsoft
has their network configured not to response to ping requests.
I will now run the command with the minus 6 switch. This will force the ping command
to use IPv6 only. Notice this time the request could not be resolved. This is because the
Microsoft site is not IPv6 ready when this video was created. This shows the next problem
with IPv6 deployment. A lot of big companies have made the switch and even some smaller
ones, but there are still a lot of organizations that only use IPv4. However, before criticizing
Microsoft too much for this, remember that they have done a lot in the deployment of
IPv6 so they can be forgiven for not having their website IPv6 ready.
Assuming that a site is IPv6 ready and so is your ISP, there is still another issue
that may arise. To demonstration this, I will open the admin page of my router. This router
is IPv6 ready and so is my ISP.
If I select the internet option, this will display my internet configuration. This includes
the username and password that are used to connect me to the internet. This will connect
me to the internet using IPv4, however, not IPv6.
Every router configuration is different; however, on this router, to configure IPv6 I need to
select the advanced tab. On the advanced tab, I next need to expand advanced setup on the
left and then select the option IPv6.
Notice the tickbox at the top, “use the same login information as IPv4 PPPoE”. This
was not ticked by default, so until I ticked this option the router was not attempting
to connect using IPv6. If I unticked this option I have the option to put a different
username and password if required. The point to remember is that additional configuration
may be required on your router to enable it to access IPv6. The other point to consider
is that even if your ISP is IPv6 ready, your router may not support IPv6.
Affordable IPv6 compatible home routers only entered the market in 2010. Most routers on
the market nowadays support IPv6; however, not all. So if you buy a new router, don’t
assume it does. If you have an old router that does not support IPv6, a firmware update
may be available to add IPv6 support, however don’t count on it.
Since full IPv6 support is not here as yet, how does Windows handle using both IPv4 and
IPv6. When both are configured this is called dual stack, it simply means both IPv4 and
IPv6 are configured on the same system. Essentially what happens is the application will open
a TCP or UDP connection. On a Windows computer with only IPv4 configured, this connection
will use the IPv4 protocol to access the network.
When IPv6 is also configured, the application can choose to use IPv4 or IPv6. In some cases
the application may choose a particular protocol, at other times it may just ask for a connection
and Windows will open either an IPv6 if possible or an IPv4 connection. This essentially means
any device on the network can have IPv4, IPv6 or both protocols configured.
This brings us to the different node types. A device running only IPv4 is an IPv4 node
type. A device running IPv6 an IPv6 node. A device running both IPv4 and IPv6 is an
IPv4 IPv6 node. This becomes important when using transition technology and tunneling.
Transition technology is designed to help the deployment of IPv6 on the internet. There
are many different times it may be used, for example bridging two IPv6 networks when only
the IPv4 network is in-between. Thus it’s important to understand which node types the
transition technology is designed to work with. If you are using tunneling, for example
a VPN, it may only work with IPv4 and thus the IPv6 protocol may no longer be available.
To end this video, I will perform a quick summary of what you need to do to access IPv6.
First your ISP needs to be IPv6 ready. Even though IPv6 has been developed enough to be
useable for over 15 years, ISPs have been slow to add this service to their networks.
IPv6 equipment, especially when first developed, was quite expensive and a lot of ISP’s did
not want to replace old equipment just to add IPv6 support.
The next requirement is that your router needs to be IPv6 ready. Affordable IPv6 ready home
routers have only been around for the last 5 years but it is still possible today to
buy a router that is not IPv6 ready. Check before you buy. If you purchase one, also
remember that it may need extra configuration to allow IPv6 support.
The last point to remember is that the destination must also be IPv6. With limited support from
the ISP’s, it is no wonder that a lot of sites on the internet are IPv4 only. It will
be a while yet before the majority of the internet is reachable using IPv6, but that
is slowly changing.
Remember that both Windows and Linux systems support the use of both protocols
at once, referred to as dual stack. This helps with the transition process as the administrator
simply needs to configure both. They don’t need to choose.
In some cases, you may need to access an IPv6 network, however there is limited IPv6 support
between the host and the destination. When this occurs, a transition technology may be
used. But this is the topic of the next video. Until then, I would like to thank you for
watching and look forward to seeing you in the next video.