I’m sure most of the people working with technology are familiar with the terms IPv4 and IPv6. In a nutshell – every device connected on a network (Internet or private network) requires an IP address in order to “communicate” to other devices. The current standard for these addresses is called IPv4 (Internet Protocol version 4), and it forms the foundation of most Internet communication today. IPv4 however suffers from several important shortfalls, most importantly the lack of sufficient address space. For that reason, IPv6 was developed which introduces a number of other improvements especially to QoS (Quality of Service) and Security.
In order to utilize a device for a video conference, regardless whether it is a high end video codec or a smartphone, that device needs to be connected to a network, so naturally it will require an IP address. Without going in too much technical details, but still mentioning the most important terms, let’s see how IPv6 features will affect video communication.
Huge address space
The most important benefit of IPv6 implementations is that it will provide virtually unlimited address space, by introducing 128-bit address, versus the 32-bit address used by IPv4. Just as an analogy, it will be enough to assign IPv6 address to every atom on the earth and still have enough left to do another 100+ earths. This will allow virtually any device in future to be assigned a globally reachable address, which in turn means that NAT (Network Address Translation) will be no longer necessary in the long term, and removing NAT from the equation will solve a lot of the interoperability issues in real-time services such as VoIP and Videoconferencing. It will also be possible to assign multiple network addresses to devices which means they can stay connected to several different networks at the same time.
Improved Quality of Service (QoS)
Quality of Service refers to the ability of the network to prioritize certain traffic to other and is especially important to VoIP (Voice over IP) and Video Communication, since we don’t want to have any delay here. The way data is transmitted in today’s IP networks is in form of network packets. These packets consist of two parts: packet header – containing control information, and payload – containing the used data. IPv6 improves over IPv4 in terms of QoS is by introducing new field in the packet header called “Flow Label”. This “label” is used to identify and prioritize certain packet flow, for eg. video stream and allows devices on the same path (routers, switches…) to read the flow label and take appropriate action based on it.
With IPv6, addresses can be assigned automatically and dynamically by the client device, by getting the network prefix from any router it finds and then generate the full IP address for that network, based on the hardware MAC address. This means there will be no need for DHCP servers like with IPv4, and also less configuration requirements. DHCPv6 will of course still be available for assigning IPv6 addresses.
IPv6 will provide better security than IPv4 when it comes to authentication and encryption of the transmitted data. The main reason for that is IPsec – a security protocol that is mandatory for IPv6 systems, and only optional for IPv4 environments. IPsec is defined as a set of security standards, originally written as part of the IPv6 specifications, and allows data to be secured from the originating to the destination host (through the various network elements such as routers, gateways…) by maintaining data confidentiality, integrity and authentication at the network layer. Another security improvement comes from the fact that IPv6 subnets will be so large so any attempt for hackers to scan them searching for a specific host will be ineffective.
Mobility refers to the ability of a device to move between different IP networks and still maintain the same IP address. This is very important for IP enabled real-time communication services, no one wants to be disconnected from a call while moving from one physical location to another. For that purpose, the Mobile IP protocol was designed by IETF. This protocol was further enhanced with Mobile IPv6 and Hierarchical Mobile IPv6 (HMIPv6) which propose higher level of security and more efficient data transmitting.
Big packets and improved routing
Another benefit to visual communications is IPv6 support for very big packet payloads, up to 4 billion bytes (IPv4 supports up to 65535 bytes only). With bandwidth becoming cheaper and the increase in device processing power, supporting big packets delivery will be important when dealing with high quality multimedia content of the future. Even though the packet can be a lot bigger than in IPv4 systems, the actual routing of the information is improved due to the simplified packet header and structured approach to addressing, which reduces the amount of information network routers must store and leads to faster packet forwarding.
When talking about IPv6 impact on the network, it is very important to consider the migration strategy as well, from Ipv4 to IPv6. Basically there are three ways to manage this: dual-stack implementation where all the network components and devices support both IPv4 and IPv6, tunneling – is implementation method where IPv4 packets get encapsulated and transported over IPv6 network backbone, and proxy translation – where network border element performs the mapping of packets from one IP version to another.
Most likely, providers and businesses will opt to upgrade the existing network infrastructure to dual stack in order to support both customers. Some network elements that do not support dual-stack mode will have to be upgraded or replaced and new infrastructure that will be deployed will have to support IPv6 dual stack from the beginning.
Each migration strategy will definitely introduce certain level of latency in the network, so that is just a reason more that all services must be properly tested before a production rollout.