wireless professional
One of the most transformative technology trends of the past decade is the availability and growing expectation of ubiquitous connectivity. Whether it is for checking email, carrying a voice conversation, web browsing, or myriad other use cases, we now expect to be able to access these online services regardless of location, time, or circumstance: on the run, while standing in line, at the office, on a subway, while in flight, and everywhere in between. Today, we are still often forced to be proactive about finding connectivity (e.g., looking for a nearby WiFi hotspot) but without a doubt, the future is about ubiquitous connectivity where access to the Internet is omnipresent.
Wireless networks are at the epicenter of this trend. At its broadest, a wireless network refers to any network not connected by cables, which is what enables the desired convenience and mobility for the user. Not surprisingly, given the myriad different use cases and applications, we should also expect to see dozens of different wireless technologies to meet the needs, each with its own performance characteristics and each optimized for a specific task and context. Today, we already have over a dozen widespread wireless technologies in use: WiFi, Bluetooth, ZigBee, NFC, WiMAX, LTE, HSPA, EV-DO, earlier 3G standards, satellite services, and more.
As such, given the diversity, it is not wise to make sweeping generalizations about performance of wireless networks. However, the good news is that most wireless technologies operate on common principles, have common trade-offs, and are subject to common performance criteria and constraints. Once we uncover and understand these fundamental principles of wireless performance, most of the other pieces will begin to automatically fall into place.
Further, while the mechanics of data delivery via radio communication are fundamentally different from the tethered world, the outcome as experienced by the user is, or should be, all the same—same performance, same results. In the long run all applications are and will be delivered over wireless networks; it just may be the case that some will be accessed more frequently over wireless than others. There is no such thing as a wired application, and there is zero demand for such a distinction.
All applications should perform well regardless of underlying connectivity. As a user, you should not care about the underlying technology in use, but as developers we must think ahead and architect our applications to anticipate the differences between the different types of networks. And the good news is every optimization that we apply for wireless networks will translate to a better experience in all other contexts. Let’s dive in.
§Types of Wireless Networks
A network is a group of devices connected to one another. In the case of wireless networks, radio communication is usually the medium of choice. However, even within the radio-powered subset, there are dozens of different technologies designed for use at different scales, topologies, and for dramatically different use cases. One way to illustrate this difference is to partition the use cases based on their "geographic range":
| Type | Range | Applications | Standards |
|---|---|---|---|
| Personal area network (PAN) | Within reach of a person | Cable replacement for peripherals | Bluetooth, ZigBee, NFC |
| Local area network (LAN) | Within a building or campus | Wireless extension of wired network | IEEE 802.11 (WiFi) |
| Metropolitan area network (MAN) | Within a city | Wireless inter-network connectivity | IEEE 802.15 (WiMAX) |
| Wide area network (WAN) | Worldwide | Wireless network access | Cellular (UMTS, LTE, etc.) |
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