Introduction: IPv4 Exhaustion

To communicate on the internet, a unique IP address is needed. An IP address is a chain of multiple bits that can identify a particular host over an IP network. It may seem obvious that a lot of these IP addresses are needed to maintain the global net and keep up with the addition of innumerous new hosts. 

On the early years of the internet, the computer scientists from the time thought that one IP address for each person in the world would suffice. IPv4 can support 4,294,967,296 addresses, which was about the world population in 1981.

For every new device on the internet, there is one less IP address available. As population grew and internet access became widespread, the number of devices rose exponentially and IP addresses vanished.

Figure 1: Amount of /8 IPv4 Addresses Exhaustion

Looking for Solutions: IPv6

Since the 80's, IT Engineers have been concerned with IPv4 exhaustion and have been developing solutions ever since, like CIDR on the 90's and NAT. 

In 2012, the IPv6 protocol was formalized, the newest version of the Internet Protocol. Instead of using 32 bit addresses like IPv4, it uses a 128 bit address. These ones will take a much longer to be extinguished. 

Implantation: Dual Stack

The downside is that IPv4 networks are not totally compatible with IPv6, since both are different protocols, with different encapsulations. With this, applying IPv6 to current IPv4 networks needs a specific approach, which we describe Dual Stack.

Figure 2: Dual Stack Layering

Dual Stack is the technology that lets IPv4/IPv6 networks to talk to each other. It tries IPv6 connection and if it is not successful, then it tries IPv4 communication. Dual Stack networks are supposed to act as a smooth transaction between both technologies, until all networks have been brought over to the latest IP version.

Huawei ONT

Huawei ONTs are already up to speed on IPv6 and are already able to get IPv4 and IPv6 addresses interchangeably. Looking at the WAN configuration page on the EchoLife EG8145V5, we can see Dual Stack IPoE and PPPoE options:

Figure 3: EG8145V5 WAN Dual Stack Options

By changing this option from IPv4 to the Dual Stack option, the ONT will seamlessly request for an IPv6 address as well.

Beyond WAN configuration, the ONT WEB GUI also gives different options for IPv6 networking, including: 

• DHCPv6;

• IPv6 Firewall;

• IPv6 Filtering;

• Default IPv6 Route;

• IPv6 Static Route;

• IPv6 Port Mapping;