Chaz,
Good article on Roaming pertinent to our discussion of GRX on another thread:
>> Ready to Roam
13th October 2000
Annie Turner
UMTS Daily
The GSM Association's sell-out GPRS Conference & Vendor Workshop in August this year highlighted a plethora of issues arising from the collision of the wireless and IP worlds.
The GPRS conference itself was part of an Association-led initiative to drive the understanding, development and implementation of GPRS roaming for operators. Roaming, of course, is one of the main reasons for GSM's phenomenal success. The technology now allows approaching 400 million GSM subscribers to use their own phone number and handset in more than 150 countries, and the demand is huge. During the summer of 2000, the number of voice roaming calls hit an all-time high at more than 750 million incpming calls per month.
The GSM Association is working in partnerships across the industry to ensure that the benefits of voice and non-voice roaming are extended throughout wireless industry as well as ensuring that GSM evolves smoothly andcohesively towards 3GSM and beyond. It is expected that the first GPRS roaming agreements will be operational in the third quarter of this year. Over the coming months, GPRS roaming service will spread as networks are commercially launched by operators.
Already, roaming is possible between GSM and iDEN (Motorola's integrated Digital Enhanced Network), while GSM/TDMA handsets should become available in the second quarter of 2001 with GSM/ narrowband CDMA terminals coming on to the market a few months later. It is not yet clear when GSM/TETRA handsets will be launched, but work continues apace in the Association-led Global Roaming Forum.
Another evolutionary step following GPRS will be EDGE, bringing even higher data rates to GSM. EDGE is also being adopted by the TDMA operators enabling them-especially in the USA-to deploy UMTS-Iike services, already being referred to as 3GSM. Some TDMA operators might stick with that technology instead of eventually moving straight to 3G; much will depend upon the regulatory environment in which they operate, their business goals and their network architecture.
Inter-standard roaming is not a side show to the main event- the evolution to the next generation-since the industry is already tying the existing disparate 2G technologies together to fill in the gaps in global roaming. The various strands of development on inter- standard as well as 2G/3G roaming were brought together in 2000 with the establishment of the Global Roaming Forum. The Association wants GSM customers everywhere, now and in the future, to be able to roam wherever they are, whatever the technology, with the GSM global network at the core.
Naturally this presents a number of challenges, with the immediate one being to enable roaming between GPRS networks. This will be a bigger leap than putting roaming in place between GPRS and 3G because GSM/GPRS roaming involves a major transition from circuit to packet switching using an IP-based infrastructure. There will also be the need to determine how a service that would use GPRS at home will be supported on a visited GSM network which does not yet have GPRS.
The Association set up the GPRS Roaming Initiative earlier this year to tackle the deployment and operational issues surrounding it. This is the first time that the attributes of mobile and the Internet (whence of course IP came) have been brought together. There has been much talk of the convergence of mobile and the Internet; they may merge or simply co-exist. Either way GSM can fulfil its promise.
The other great challenge is that, so far, roaming has applied to predominantly voice calls whereas it must now progress to embrace high-speed data, including video and images. The Association has built on its voice roaming experience, evolving the technical principles used for GSM/GPRS roaming. The good news is that progress is far further advanced than was the case with voice roaming in 1993 due to a more proactive approach for GPRS and the benefit of many years experience of GSM roaming. It is likely that the biggest obstacle to GPRS commercial services getting off the ground quickly will be a lack of handsets in sufficient quantity.
It is expected that by the middle of 2001, GPRS with roaming facilities will be deployed by a significant number of carriers around the world. Around five years from now, IP will be at the heart of wireless communications, which has big implications for operators and users alike. Operators.will enjoy the benefits of running a quality 'pipe' that will mean that wherever a mobile customer goes, they can access their home network and carry their mobile environment with them.
In the meantime, the way forward for existing 2GSM network operators is to evolve their networks to offer 3GSM type services through GPRS to EDGE or from GPRS to 3GSM. There are potential pitfalls before IP roaming utopia is eventually reached. Firstly, the notion that for 3G only the appropriate building blocks should be put in place to support services but that the services themselves should not be standardised, is being questioned. The Association firmly believes that one of the main reasons for GSM's roaming success is because a basic standard of services was defined which behaved the same on any visited network.
Secondly, 2GSM needs to progressively support 3GSM services rather than having each call drop back to the lowest common denominator. For example, 2GSM would struggle to handle a call that involved video streaming. Ultimately, 2GSM and 3GSM will simply be different radio access technologies that use the same GSM core network, so this situation will not arise.
Thirdly, it is important that the 2GSM networks are able to support 3G roamers if the new 3G operators' business models are going to work, since they will rely upon 3G/2G roaming in the early stages of their network rollout. However, if they differentiate themselves from their competitors mainly by "3G only" services and their customers can only get basic 2GSM coverage in some areas, it will drive a coach and horses through their business cases.
And lastly to ensure universal GSM service it is essential that 3G networks are able to carry 2GSM voice calls-so that, where there is no 2GSM network but there is a 3G network, a GSM subscriber with a multi mode handset can still make a call.
As yet there has been no in-depth work undertaken on 3G roaming or 2G/3G roaming but from the understanding gained from work undertaken on GPRS so far, it is being designed in a way that should obviate any serious technical difficulties. As john Hoffman who leads the GPRS Roaming Initiative commented: "Think of it like building a highway; building that first lane is tough, but it's much easier to add new lanes later-we're building several lanes now." <<
- Eric - |
