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Thursday, 6 March 2008

IPv6! One small step for man, one giant leap for mankind


3G Americas has published a whitepaper urging wireless service providers to start making a transition plan asap.


Anyone who has studied TCP/IP in their studies would know the basic problem with IPv4 is that the address is only 32 bits long and this allows a theoretical maximum of 2^32 addresses. Ofcourse practically the number would be far less because some of the address are either reserved or wasted due to the way the networks are designed (Subnets, etc).

To overcome this sometime in the beginning of 1990's IPv6 was formulated with 128 bit address. This would mean unique IP address to every street lamp is possible without us worrying about depletion of the addresses. Ofcourse the human nature is such that they dont change their behaviour untill forced to and this is the same reason IPv6 is not been used popularly.

When 3G was being standardised one of the main goals was also to use IPv6 exclusively but then everyone chickened out citing various problems and continuity of services.

Anyway, this new 3G Americas paper has laid down a plan and possible pitfalls that would be encountered when transitioning to IPv6. The following is a self explanatory summary for the report:

To transition to IPv6 or not? A critical question for many service providers is when to transition to IPv6. As pointed out earlier, IPv6 has several benefits which will result in a simpler, more powerful and more efficient network. The sooner a service provider achieves these benefits, the sooner it will be at a competitive advantage compared to service providers who delay transition. The risks of delaying the transition are the following:

 Managing a dwindling IPv4 address space will become increasingly expensive. Address
allocation requires careful planning; previously assigned address blocks may need to be
recovered, which is a complex process; and the management of additional devices such as
Network Address Translation (NAT) devices add to the cost.

 The service provider that delays transition to IPv6 may not be able to deliver the same
services as service providers that have made the transition to IPv6. The ability to support
always-on and peer-to-peer services is impaired when traffic has to traverse NAT devices.
For example, always-on services require that a user is always reachable and therefore
cannot share a pool of public addresses with other devices. This can be mitigated through
address and port translation, but also that has its limitations.

 At some point, a service provider who has not made the transition to IPv6 may become
unattractive as a roaming partner to service providers who have made the transition. The
same may be true in retail/wholesale relationships.

On the other hand, transitioning to IPv6 at an early stage also has certain risks. The transitioning process is complex. It requires a significant investment in planning and training. During the transition period, the service provider must run both IPv4 and IPv6 systems concurrently, which leads to an increase in operational expenses. Furthermore, there is a risk of service interruption, customer dissatisfaction and penalties. All service providers will need to go through this, but an early adopter may run into problems which later adopters could avoid.

In the end, we believe that service providers don’t have the option to delay IPv6 introduction. The exhaustion of IPv4 addresses will force a transition to IPv6, and as pointed out earlier, address exhaustion may become a reality within the next five years. From that point on, service providers will face an increase in operations cost, if not because of introduction of IPv6, then due to the complexity of running an IPv4-only network with a diminishing pool of addresses.

With careful planning, the risk of early adoption can be mitigated significantly.

2 comments:

c-webb said...

Hello Zahid,
i am student from Bosnia and Herzegovina and my english is not so well. :) Your blog is very interesting. I wanted to ask you if you can help me with some thing. I have to finish my graduate work (i dont know how to call it) and i need to wrote something about "IMS over HSPA". Can you tell me where to find some literature about this? I have this books: "Convergence technologies for 3g networks, The 3G IP Multimedia Subsystem" but i need
something like - IMS over HSPA architecture or how to build IMS network over HSPA....
Thanks.

Zahid Ghadialy said...

Hi c-webb,

IMS in 3GPP was started in Release 5, the same time as HSDPA so IMS is by default on HSPA network. The participants of HSPA are the UE, Node B and RNC whereas IMS is more concerned above RNC so in a way they are not related. Anyway, the books should give you a good idea. When the books talk about RNC, etc they are referring to HSPA network.

Hope that helps.