Nextel is getting together with some technology industry leaders, including Cisco, Nortel, and IBM, to test wireless broadband access. The new fourth generation (4G) wireless offering is made possible by using FLASH-OFDM technology from Flarion Technologies. Nextel is expecting to be able to provide consistent download speeds of 1.5Mbps, with burst speeds of up to 3.0Mbps.
The trial will be made up of employees from the participating companies. Nextel will evaluate the network performance and customer satisfaction during the trial period, which is expected to last at least 6 months.
Nextel's press release. Read more on this topic at CNET.
I know it will be a long time before this is both technically and fiscally realistic, but boy, would it be cool! This goes beyond connecting from home–this could be huge for business. Imagine being able to drop a T-1's worth of bandwidth anywhere you wanted.
The question is, how long will it be before this is in the mainstream, before it is cost-effective? I could use it yesterday, but I have a feeling it will take a lot longer than that. Realistically, I'm guessing three to 5 years.
This is the wave of the future, and Nextel is trying hard to get out ahead. And with companies like Cisco and IBM stepping up to try it out, it appears Nextel is heading in the right direction.
… what Nextel's definition of "highly secure" is…?
While true from a technical standpoint, the statement falls short on practicality.
You do need to search for a "hotspot" of sorts: you need to be near a Nextel cell tower for the service to work. Except in this case, the hotspots have a 2 to 4 mile radius.
Also, cell coverage can be spotty during inclement weather, so I doubt this service is going to replace hardwired connections for mission-critical applications.
First, about cellular generations. Having worked in the industry for a while, I have a narrower view what 1G, 2G, 3G, 4G, etc. mean. First 1G service was based on a TDM voice infrastructure — built around class x switches and 64 kbps slots. It had data, but circuit switched over a 64Kpbs voice bearer.
Second, 2G service had the same switched TDM backbone, but added a true Data Bearer and a digital voice bearer. Data rates were still limited to the max 64kbps of a single time slot.
2.5G added a packet bearer to the mix, still limited to 64kbps slots.
Third generation (3G) changed the backbone slightly to allow a full T1 or E1 or J1 to be consumed by a data sub-scriber, but is still based on an ISDN style backbone. Sure you have packet switched data, but its carried over a traditional TDM backbone. There still a circuit voice backbone and while the data rates are high enough for VoIP, the latency of the data service is to great to base all of the "bearer services" on it, so you still have circuit voice, circuit data and packet data bearers.
Finally, 4G systems will utilize a packet infrastructure rather than a traditional telephone architecture. Services will be horizontally layered on top of a proper low latency, QoS enabled packet switch (read IP) infrastructure. Gone will be the circuit voice and circuit data bearers.
So "G" has more to do with the infra-structure and less to do with the data rates. The data rates over the air are driven by the organization of the infrastructure and other than that have little to do with what generation they are.
In that sense, this NexTel trial is a 4G trial. BTW, I'm a participant in that trial. If folks are interested, I'll post some results that I might be able to share.
Are you saying that 4G is a derivitive of VoIP (as used by many large businesses for their telephony infastructure)? What would the range be from one cell/base station (as in, would range drop from 2G or 3G devices)?
Not exactly, I'm saying that 4G only has one bearer over the RF channel and that's packet data. Over that packet data bearer, you have services like VoIP layered over top of it. In addition, the infrastructure of a 4G network is all IP. VoIP gateways and gatekeepers handle calls to "legacy" circuit switched voice networks. Additionally, IP technologies for authentication, security, mobility and traffic shaping manage access to the network and protect its subscribers. That's what makes this 4G.
In the NexTel/Flarion incarnation of a 4G network data rates are high, even while mobile and when there is no clear "line of sight" between a subscriber and a base station. Some networks will use different frequencies and different modulation techniques and have different data rates, however the important thing is that the "value added" services like voice, video, messaging and data will work homogenously across all of them — because they will be all IP networks.
4G technologies have been in development for a while. If it wasn't for economic conditions, I'd suspect that most carriers would deploy them within 2 years — effectively bypassing most of the 3G rollout.
What's on the horizon is 5G. In 5G there will be no difference between a base station and a client/mobile phone/etc. Devices will roam using MANET technologies and packets will be "routed" by client as well as infrastructured devices. The burden of building an infrastructure will be shared between subscribers and carriers — as more subscribers are added to the networks, the infrastructure will grow by using a fraction of every devices resources to create more capacity.
I don't see how the clients will be able to constantly take and hand off packets for other clients with current battery life..
Actually, by relaying packets along you might consume LESS energy since instead of having to send data miles to the nearest base station, you would route the data to say a neighbor several feet away (at much much lower power levels.) That neighbour in turn relays the packet on.
The key to this is to have power aware routing and strong power control. The power aware routing would have to understand the latency requirements of each packet. Low latency packets (eg., voice) would be sent at higher power levels and fewer hops.
Very good point and explanation..
Combined with the traditional hi-output base stations for situations where there is nobody else around to exchange packets with, this does sound feasible.
spraying 2.4ghz all over the band.
Combined with the traditional hi-output base stations for situations is good idea but how about the QoS? The QoS will be inconsistant all the time.