This blog entry is the fourth in a row about my thoughts on the current development of 4G wireless standards. You might want to take a look at the introduction before reading on. Previously, I’ve discussed why 4G networks are necessary and what to generally expect of 4G wireless networks. Three different standards are currently emerging and have already started to compete with each other for global dominance:
- WiMAX aka IEEE 802.16e
- UMTS Long Term Evolution (LTE)
- CDMA EVDO Rev. C (also dubbed DORC)
All of the contenders are still paper ware only and widespread adoption of 4G technologies is still several years away. So how can they already compete with each other? From my point of view there are three axis of competition today:
Time to Market
As all three types of networks have similar properties, time to market will be an essential component of the overall competitiveness of a standard.
- WiMAX is set to enter the market first as the air interface part of the standard, which is called IEEE 802.16e-2005, has already been approved by the members of the IEEE standards body back in February 2006. For those of you how like to read standards documents, you can find it here. Standards for the network infrastructure are specified by the WiMAX forum and you can download the latest drafts from this location. Here, work seems to be quite advanced but the standard has not been approved yet.
- The 3GPP has also started its activities around 4G and the UMTS Long Term Evolution (LTE) standardization is well on track. First fruits of their work can be downloaded from www.3gpp.org. The most interesting documents are 25.913 on requirements, the 25.912 feasibility study and 23.882, a report on different implementation options. To me, it looks like the work on the WiMAX standards is 12 to 24 months ahead of the LTE work.
- The work on CDMA EVDO Rev. C seems to be even further behind WiMAX which might be because the CDMA Development Group is still working on EVDO Rev. B, the multi carrier extension for current EVDO Rev. A networks.
User Base of 3G Predecessor Technology
Having a predecessor technology already in place is a great help in introducing a new technology especially if new devices are backwards compatible to existing networks. Here, LTE has a big advantage as the standard will most likely be defined in such a way. Thus, handsets and other mobile devices will not only work in LTE networks but also in 3G UMTS networks and most likely also in 2G GSM/GPRS/EDGE networks. This is especially important in the first few years of network deployments when coverage is still limited to big cities. EVDO Rev C. is likely to follow a similar path.
WiMAX on the other hand is not backwards compatible to any previous wireless network standard. Thus, it remains to be seen if devices will also include a 3G UMTS or EVDO chip. This is not only a question of technology but also a question of strategy. If a company with a previously installed 2G/3G network deploys WiMAX then they will surely be keen on offering such handsets. New alternative operators without an already existing network on the other hand might be reluctant to offer such handsets as they would have to partner with an already existing network operator. They might not have much of a choice though if they want to reach a wider target audience.
Migration Path
At some point current 2G and 3G network operators will migrate to a 4G network technology. As 4G network technology is based on IP only and includes no backwards compatibility for circuit switched services, current operators do not necessarily have to select the evolution path of the standard they are currently using.
For current UMTS network operators the most likely evolution path will be to LTE. Devices will most likely be backwards compatible to their existing 3G and 3.5G networks. Also, connectivity of the new LTE radio network to their existing core network infrastructure, billing systems and services will be seamless. Also, current 3.5G networks offer enough capacity for a number of years to come. Thus, UMTS operators are currently in no hurry with 4G technologies. Nevertheless, I think that WiMAX might have a chance with some operators trying a different game to see if they can gain a competitive advantage. In my opinion, the availability of dual mode handsets will be crucial for such a decision. In theory, UMTS operators might also choose EVDO Rev. C. I don’t think this is likely though due to the standard being nowhere on the horizon yet and the fact that the current EVDO market share is on the decline.
For EVDO operators the picture is a bit different. For them, EVDO Rev. C is still far out. Some of them especially in Taiwan and Australia have decided to make a radical move even sooner and are in the process of migrating from the current 3.5G EVDO networks to 3.5G UMTS/HSDPA. Recently, Sprint in the U.S. has made another early decision and announced that they have chosen WiMAX as their 4G technology instead of Rev. C and will start with the rollout of the network in 2007.
Summary
In the end I am quite convinced that at least two technologies will gain global traction. If WiMAX is one of them, and I am quite convinced that it will be, there will be even more competition in the wireless domain than today. The disadvantage of WiMAX of not having a network legacy could in the end be a major advantage. It will allow new companies to enter the market more easily and thus increase competition, network coverage, services and hopefully decrease prices.
Thanks a lot. I found the article useful. Especially the link to the LTE 3GPP specifications document.
Wonder if when the official 802.11N will be ractified? And once it is certified how long will it take for .11 N to replace G in both access points and embedded PCs?
This article is very usefull. LTE is going to have wide impact and in another 10 years (possible transition time from circuit sitching to packet-switching or say nG to 4G n=2,3,3.5) LTE willbe most favoured one among the three listed by you (WiMax, 3G LTE, EVDO Rev C.).
Excellent information !!