Editing Wireless network (section)

=== Difficulties ===

==== Interference ====
Compared to wired systems, wireless networks are frequently subject to [[electromagnetic interference]]. This can be caused by other networks or other types of equipment that generate radio waves that are within, or close, to the radio bands used for communication. Interference can degrade the signal or cause the system to fail.<ref name="Zander" />

==== Absorption and reflection ====
Some materials cause [[Absorption (electromagnetic radiation)|absorption]] of electromagnetic waves, preventing it from reaching the receiver, in other cases, particularly with metallic or conductive materials reflection occurs. This can cause dead zones where no reception is available. Aluminium foiled thermal isolation in modern homes can easily reduce indoor mobile signals by 10&nbsp;dB frequently leading to complaints about the bad reception of long-distance rural cell signals.

==== Multipath fading ====
In [[multipath fading]] two or more different routes taken by the signal, due to reflections, can cause the signal to cancel out each other at certain locations, and to be stronger in other places ([[upfade]]).

==== Hidden node problem ====
[[Image:Wifi hidden station problem.svg|right|thumb|200px|In a hidden node problem Station A can communicate with Station B. Station C can also communicate with Station B. However, Stations A and C cannot communicate with each other, but their signals can interfere at B.]]
The [[hidden node problem]] occurs in some types of network when a [[Node (networking)|node]] is visible from a [[wireless access point]] (AP), but not from other nodes communicating with that AP. This leads to difficulties in [[medium access control]] (collisions).

==== Exposed terminal node problem ====
[[Image:Exposed terminal problem.svg|thumb|left|200px]]
The [[exposed terminal problem]] is when a node on one network is unable to send because of [[co-channel interference]] from a node that is on a different network.

==== Shared resource problem ====
The wireless spectrum is a limited resource and shared by all nodes in the range of its transmitters. [[Bandwidth allocation]] becomes complex with multiple participating users. Often users are not aware that advertised numbers (e.g., for [[IEEE 802.11]] equipment or [[LTE (telecommunication)|LTE]] networks) are not their capacity, but shared with all other users and thus the individual user rate is far lower. With increasing demand, the [[Bandwidth allocation#Data crunch|capacity crunch]] is more and more likely to happen. [[User-in-the-loop]] (UIL) may be an alternative solution to ever upgrading to newer technologies for [[over-provisioning]].