Europe's Fresh Out Of IPv4 Addresses

From LinuxReviews
Jump to navigationJump to search

The Regional Internet Registry for Europe, the Middle East and parts of Central Asia (RIPE) announced that they "ran out of IPv4 addresses" on November 25th, 2019.

published 2019-11-28last edited 2019-12-09

Avian Carrier Backup link.jpg
Typical networking gear. The bird's function is to provide IP by Avian Carriers connectivity in case a long-lasting power-outage takes the electricity-requiring components offline.

RIPE reached their last Internet Protocol version 4 (IPv4) /8 address pool in 2012. They managed to make that /8 stretch and last seven years and now it's gone. There's currently no IPv4 subnets available for network operators in areas RIPE is responsible for.

Large European Internet Service Providers (ISPs) will no longer be able to get any new IPv4 address allocated to them. RIPE will try to recover address space when organizations go bankrupt or close for other reasons. Recovered addresses will be handed out to RIPE members who have signed up on a waiting list. Only RIPE members who have never received an IPv4 allocation (big or small does not matter) are allowed on the waiting list and those who sign up and eventually get a subnet will only be allocated a single /24. That's one gateway IP, one broadcast address and 253 potential customers a new ISP can provide IPV4 addresses to.

Very Little Will Change

The Internet won't stop and the already allocated IPv4 addresses will keep on working just fine. And RIPE running out of IPv4 address space to assign ISPs does not mean that existing ISPs have any real address shortage on their level.

The larger ISPs in Europe have plenty of IPv4 addresses. They prepared for this a decade ago. Only new ISPs will suffer; the bigger players have reserve pools to draw on.

Version 6 of the Internet Protocol was formalized by the Internet Engineering Task Force (IETF) in 1998. It uses 128-bit addresses. IPv4 and IPv6 are not compatible, a website which is only available by IPv4 can not be visited directly from an IPv6 connection. This doesn't really matter since IPv4 and IPv6 work fine side by side. Clients and servers can have both. IPv6 will be preferred and IPv4 will be a secondary choice if both versions of the Internet Protocol are available.

It's been a while since 1998. So why didn't the European ISPs roll out IPv6 to their customers a decade ago? The Linux kernel has had IPv6 support since forever and other operating systems have had support for ages. The answer is.. unclear. It could have something to do with the fact that only newer players are affected by the "IPv4 shortage". Websites and content providers have mostly been IPv6 capable for years now. This site has been reachable by IPv6 since 2006. The end-user ISPs are the ones holding IPv6 deployment back by not handing their customers IPv6 addresses along with the IPv4 addresses they get.

RIPE does call for Internet Service Providers to move forward with IPv6 deployment in their "The RIPE NCC has run out of IPv4 Addresses" press release:

"Without wide-scale IPv6 deployment, we risk heading into a future where the growth of our Internet is unnecessarily limited - not by a lack of skilled network engineers, technical equipment or investment - but by a shortage of unique network identifiers. There is still a long way to go, and we call on all stakeholders to play their role in supporting the IPv6 roll-out."

There is a slim chance that this call will be heard but it is not likely. It is more likely that the big ISPs will drag their feet until or unless there is some clear competitive advantage to IPv6 deployment. There is on the content providing side; you don't want to miss out on a percentage of potential customers due to technical issues. ISPs have no such incentives.

Some Last Words Of Advice

European ISPs will not implement IPv6 auto-configuration or send IPv6 router advertisements or offer an address with dhcp6. They are not going to make it "just work".

Many of the European ISPs do offer their customers a IPv6 /64 using the 6rd (IPv6 Rapid Deployment) protocol. It is a tunnelling technique similar to 6to4. It is stateless and encapsulates IPv6 packets into IPv4 packets. A very deep and time-consuming dig through their websites may turn up some 6rd address which can be used to get a IPv6 subnet. Searching for 6rd+NameOfISP is another way to find their 6rd address. The Swedish ISP Telia, as an example, does not list anywhere in their support documentation yet quite a few websites point out that it's there and it works. The following script can be used to configure 6rd (give you an IPv6 tunnel) on their network:

GATEWAY=`dig +short`  # 6rd gateway host
modprobe sit

### Try to autodetect the local ipv4 address
MYIPV4=`ip -o route get | sed 's/.* src \([0-9.]*\) .*/\1/'`
if [ "$MYIPV4" == "" ];then
  exit 0

# Generate an IPv6-RD address
MYIPV4_nodots=`echo ${MYIPV4} | tr . ' '`
IPV6=`printf "${PREFIX}:%02x%02x:%02x%02x::" ${MYIPV4_nodots}`
SUBNET=`printf "${PREFIX}:%02x%02x:%02x%02x" ${MYIPV4_nodots}`

## Setup the tunnel
ip tunnel add 6rd mode sit local ${MYIPV4} ttl 64
ip tunnel 6rd dev 6rd 6rd-prefix ${PREFIX}::/32
ip addr add ${IPV6}/32 dev 6rd
ip link set 6rd up
ip route add ::/0 via ::${GATEWAY} dev 6rd

The above IPv6 6rd Rapid Deployment script will work fine on other ISPs if you replace Telia's 6rd address in the GATEWAY= line with your own ISPs 6rd address.

That is, if your ISP has one 6rd at all. In case you do have native IPv6, this whole wikipage is of no practical use for you. 6rd is a transitionary technique, so advanced ISP have no need to use 6rd any longer by 2020 when they offer a fully native IPv6 dual protocol stack (i.e. both IPv4 and v6).

There is also the option of getting a free IPv6 tunnel from Hurricane Electric's IPv6 Tunnel Broker (the only global free IPv6 tunnel broker left) if you can't find an IPv6 rapid deployment address for your ISP (and if you still on IPv4 only). Hurricane Electric has end-points in most European countries and several locations in the bigger countries like Germany and France.

You might as well configure IPv6 yourself today. European ISPs are not about to just auto-configure IPv6 for you even though Europe just ran out of IPv4 addresses. [notabene: By 2020 this is not generally true any longer except maybe in some backwaters of Transsylvania.] Good luck.

If you are wondering if you should bother: Consider this. If you got 3 boxes at home and IPv6 configured both at work and at home then you'll be able to just scp (securely copy) files directly to any box at work from home and vice versa because there's no NAT. IPv6 is quite convenient.