Let’s look at the problem of the disrupted hierarchy. What needs to be done to restore balance? Because until this problem is solved, it will be very hard to justify advancements on in-home data rates. So, let give this a closer look, because now the usage pattern in the home becomes relevant: how many people are living in the home, how many rooms (floors) does your home have, how many devices are used simultaneously per user, etc.
Let’s take an example of a family of four. Internet radio is playing in one room, mom is having a video conference in another room, dad is downloading a large report on his computer, the son is playing a video game and the daughter is watching YouTube on her phone while a movie streams on the TV. This family would be very happy with 1 Gb/s to the home, a 500 Mb/s distribution system in the home, and 100 Mb/s speed access from the end device to the access point, as shown below:
As we’ve discussed, it’s getting access to the home with 1 Gb/s that is the current challenge. Although the first rollout of 10 Gb/s DOCSIS 3.1 has started, most people are still working with 100 Mb/s or less. This means that at this moment there is clearly overcapacity with all the infrastructure inside the building and the end nodes raw data rates today exceeding 1 Gb/s.
Approaching This From The Other Side
We can also ask the reverse question: when does 7 Gb/s with 802.11ad in the phone or in a tablet start making sense? Well probably if the in-home infrastructure can handle 15-20 Gb/s and the access to the home is 30-50 Gb/s. Well… that probably is going to take a while, unfortunately….
Currently fiber to the home (FTTH) is advertised at 1 Gb/s for DOCSIS 3.0. The next-generation DOCSIS 3.1 FD (full duplex) promises 10 Gb/s (in 2020?), so – we are getting up there, but there are no plans yet beyond this. Also, for distributed Wi-Fi in the home the plans with IEEE 802.11ax are not reaching beyond the 4 Gb/s for in-building distribution – but as can be found in many installations in the home or in an office: 10-100 Gb/s Ethernet may come to the rescue if needed.
So, What Can We Realistically Expect?
In the near future, we probably have to settle with end nodes using 1 Gb/s IEEE 802.11ac, the home infrastructure will use 4 Gb/s IEEE 802.11ax, and probably with something like DOCSIS 3.1 FD at 10 Gb/s. This will give a balanced picture that can be the next stabilizing point for the industry for Internet access at home and in buildings. In this scenario, all the resources are effectively balanced and put in a proper hierarchy.
Cloud Versus Edge
Interestingly, there is another solution for the broken hierarchy. But it would not be a simple one.
The concept of the solution goes something like this. Instead of doing everything “in the cloud,” this is about building a layer in between the cloud and the end-user. This layer, sometimes referred to as “edge computing,” is essentially a smart solution to pre-distribute information from the cloud to a local “super” edge-router with an integrated server.
Let’s look at an example. Someone interested in the news has a subscription that downloads all the news articles and video clips at 6 AM to her local router/server. She can browse during breakfast at 8 AM, going through the news and watching clips at incredibly high speeds and without delays. The bottleneck of getting information from the Internet has been removed. The router/server has become a traditional mailbox, in essence, and the news is kept up-to-date in her mailbox (router/server) all during the day.
From the other direction, “edge computing” is also helpful. Instead of sending a complete voice command, chat or conversation to the cloud for processing, the processing already takes place in the router, reducing the amount of data to be transmitted.
It is clear that such an architecture overhaul would be a tremendous undertaking, but it may nevertheless be a cheaper solution than rewiring all the exits from the high-speed Internet freeway. Certainly cheaper for the network providers, because in this situation the consumer will pick up the tab – either by paying for the more sophisticated edge-router and/or paying for the subscription for “edge routing” services.
What Does This All Mean?
There are several interesting consequences and conclusions to be drawn:
- IEEE 802.11ax, the emerging new Wi-Fi standard, will first appear in distributed Wi-Fi systems, as this is the first place for traffic aggregation and would benefit from higher data rates the most.
- IEEE 802.11ax for end nodes will stay more of a marketing game for a while, because the infrastructure to support the higher data rates will not be there.
- It looks like for end nodes IEEE 802.11ac will be the right choice for quite some time, avoiding the .11ax complexity and relatively small benefit. Even for lower performing end nodes, 802.11n will be a good solution for a while.
- We need a successor for IEEE 802.11ax for increasing the bandwidth of the indoor distributed Wi-Fi infrastructure. 15-25 Gb/s would be a good target. The goal should be to make 60 GHz IEEE 802.11ad relevant; maybe by defining that role for IEEE 802.11ay.
- The near future for IEEE 802.11ad and 802.11ay still looks quite bleak. Longer term, if the infrastructure is in place, then these standards will become relevant.
- The DOCSIS 3.1 FD local loop coming to our homes providing higher speed access will make tremendous improvements to what at this moment is the real bottleneck.
- Finally, there are opportunities to solve the problem in a smarter way than brute force raw data rates. An edge router functionality between the cloud and the end nodes can take away the pressure from the on-ramps and off-ramps of the Internet highway.
The best for Wi-Fi is yet to come, but it is important to look at the broader context to understand the relevance and the timing of all its new varieties.
Cees Links was the founder and CEO of GreenPeak Technologies, which is now part of Qorvo. Under his responsibility, the first wireless LANs were developed, ultimately becoming household technology integrated into PCs and notebooks. For more information, please visit www.qorvo.com.
