By Susan Campbell
The constant growth of the Internet is demanding the adoption of IPv6 and service providers must be ready with a clear strategy. Each one must be able to effectively navigate multiple technology choices and issues to define the best approach, understanding the implications and deployment options for IPv6 in both mobile and telecom environments.
A recent Alcatel-Lucent article, Making the Move to IPv6, stresses the importance of developing an IPv6 transition strategy as IPv4 addresses are nearly exhausted. Service providers have much work to do as IPv6 isn’t compatible with the technology in IPv4, introducing a number of new concepts that will change the way broadband networks are operated.
A viable alternative for the service provider is the IPv4/IPv6 operational model. To leverage the possibilities in this approach, service providers must understand the implications as they establish a clear strategy for transition.
Within the Broadband Forum, the support for IPv6 is defined as TR-187 and includes using Point-to-Point Protocol over Ethernet (PPPoX) and/or Asynchronous Transfer Mode (ATM). With the introduction of IPv6 using PPPoX/Layer 2 Tunneling Protocol (L2TP), no implications are suggested for access and aggregation within network elements.
To ensure IPv6 support within the telco environment, the PPPoX IPv6 Control Protocol (CP) must be in place; a prefix LAN address assignment through DHCPv6 Prefix Delegation; additional configuration parameters secured with stateless DHCPv6; RG management IPv6 addresses obtained with stateful DCHPv6 when numbered RG model is in place; and the assignment of default Gateway (GW) when route advertisements are present.
The adoption of IPv6 can also be enabled with the Bridged Residential Gateway, which requires PPPoX IPv6CP for LLA assignment; SLAAC to ensure Global-Unicast IPv6 addresses are obtained by the host; stateless DHCP to gain access to additional configuration parameters; and route advertisements to assign the default GW assignment.
The alternative to PPPoE in the adoption of IPv6 is to leverage IPoE,or Broadband Forum specification TR-177. The implications for selecting this deployment method depend entirely on the selected VLAN model, as well as the operational model of the home gateway, whether it is routed or bridged.
While service providers have a lot to consider in making the transition from IPv4 to IPv6 connectivity, other considerations have implications that can dictate the transition strategy put in place.
For one, network connectivity has to be initiated from the inside toward the outside, which could demand the deployment of a new port; private IP address space has a limited size; certain Internet services will no longer identify a hosted based on IP address; and solution selection should be based on ability to deploy both through centralized or distributed approaches as requirements can change over time. This includes making accommodation for the growing machine-to-machine (M2M) traffic whose explosive growth is coming based on the increased deployment of smart grids.
A number of challenges still exist for service providers seeking the adoption of IPv6 technologies to support both telco and mobile environments and enable customers to take broadband everywhere. A clear examination of current environments and challenges is a must, while partnering with a provider like Alcatel-Lucent could help identify the necessary tools and capabilities to have in place to move forward.
