I think anyone who like me has devoted part of his career to deal with customers, understand what I mean. How many times have we had to deal with customers reluctant to understand why a device that "makes the same" as his new ACME switch worth more than twice? Or that their beautiful WiFi access point  that connects with great coverage worth 10 times less than the one you're trying to sell?

Sometimes the best way to answer these kind of questions is position the technology in its market and compare it with the other competitors. The answer is not simple at all, because it depends entirely on the technology that we are dealing with and the specific needs of the moment.

Today in particular I will focus on one of the markets in Spain that are most affected by bad press or false promises, Wimax market. This wireless technology which we have already spoken at length in Telequismo has one of the larger markets in terms of number of manufacturers and technologies used to provide wireless broadband connectivity.

Before we start with the analysis we need to clarify that many of the equipments that we will name in this post should be considered rather than Wimax WiFi equipment, but as the manufacturers have decided to sell in Wimax way, we noted them in this study.

In this first post we will analyze the current state of the market, focusing on categorizing devices through the protocol that they used in the transmission of information. We can distinguish basically four: 802.11 (a / b / g / n), 802.11 (TDD), 802.16d / e and owner. Obviously each has its strengths and weaknesses and within each category there will be equipments of very different nature. The following table provides an interesting summary of the four protocols mentioned above:

At this point is when the question arises. What are the differences between them and why do they differ in cost about 10 times from each other?

As we mentioned earlier the answer is not simple because a device may be optimal for a scenario and bad for another, that's where you should pay full attention on the specific needs of each project.

The best way to make the approach is to analyze in detail each of the categories to see if they cover the requirements that each project might have.

We start with 802.11 based solutions. Usually they are solutions with a very competitive price whose performance is very interesting in terms of capacity and spectrum efficiency in scenarios with fully "clean" spectrum. We say this since they require the use of 40 MHz channels to provide maximum capacity and this amount of bandwidht is rarely available in unlicensed bands like 2,4 or 5,4 GHz. In addition, except for a few exceptions (Radwin is one of them), these solutions do not have mechanisms that allow synchronization so that the growth of the network is really committed to this. Keep in mind that at the time we need to install a certain amount of equipment on the same site these mechanisms are really as you can check in this post.

For solutions based on 802.16d/e, we can speak at length. But today we will focus only on the conditions associated with the performance and capabilities of this technology. The main feature of these devices is that they are the only ones that allow interoperability, ie, they have the ability to connect a subscriber of a vendor with a base station of another vendor. Furthermore it should be noted that the mere fact of being subjected to a standard is in my point of view already an advantage. It forces the vendor to fulfill certain conditions defined by the IEEE, which is always a guarantee of quality in a system. But in terms of actual performance meet the standard fact has its pros and cons. On one side the upload capacity that can provide solutions based on this standard are really far from the one any of the other protocols can offer. On the other hand latency associated with these systems is higher than the rest because the necessity of having to adapt the frame to the structure defined in the standard.

I have left the teams based on proprietary protocols to the end of this post. In this category the manufacturers do their own design for the management of physical and link levels, with the consequences that it has. On one hand the performance is optimized because they use ​​solutions tailored to the needs of each product. This allows to offer capacity, latency, number of subscribers, ... above the other protocols, although that may have a slightly higher cost than their opponents. The truth is that these systems often provide a differential value in situations where the proper management of the radio becomes essential. Since the protocols are based on proprietary design, the hardware is implemented as the same. This allows these devices to optimize the spectrum use, improve the ratio Mb / Hz, manage interference tolerance differently from 802.11 based equipment, ...

At this point I think that it is more practical to analyse the most typical usage scenarios (WISP, broadband for corporate networks and backbone for carriers) of this type of equipment and offer my personal opinion about the best solutions for carry them out, but we are going to leave that for my next post

Toni Martínez

· http://www.telequismo.com

· @toni_mart