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Wireless Sensor Network (WSN) and Ad hoc Network differ in one important factor: Infrastructure-based vs Infrastructure-less. In WSN, network is managed by a base station such as these antenna around us that receive our data and phone calls. However, I don't understand how Ad hoc is really managed (At least I don't see its application in my daily life). Can someone explain how Ad hoc is managed? Special type of base station maybe!

Thank you.

  • Thank you ... Can we say Ad hoc is a sub-type of WSN ? – Steven Nov 30 '16 at 18:11
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can provide and accept your own answer. – Ron Maupin Feb 19 '18 at 20:05
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Just so we're clear on terminology, in the 802.11 spec, Ad-Hoc is a mode of operation of the wireless client interface - this allows direct connectivity between two (or more) wireless stations that have the same SSID configured.

This is as opposed to Infrastructure mode in which the wireless interface or station must be able to associate to an Access Point in order to communicate.

A wireless interface can only be in one of these modes at a time, so either associated to an AP (infrastructure mode), or directly communicating with another wireless client (Ad-Hoc mode).

To answer your question though, Ad-Hoc mode is completely unmanaged - the entire channel is subject to collisions (no time-slots are allocated to wireless clients, because there is no centralised control point to do so), and Hidden-Node is a very real problem (Client A can hear B, but not C).

This is why it is frequently used for simple, very short-range, point-to-point use-cases such as phone tethering or first-time setup for printers and the like.

As wireless sensor networks and IoT buzzwords have come to the fore, the term "Ad-Hoc" networking has been re-used here, which is probably where the confusion comes from.

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    In 802.11 terms, two STAs form an IBSS (Independent Basic Service Set). The standard only references "ad hoc" as a "venacular (sic) term for an IBSS". However ad hoc networks are not limited to 802.11 networks, the model is widely used by other wireless communications as well. Also, AFAIK, most phone tethering is done by the phone performing the role of an access point, and is not an ad hoc network. – YLearn Nov 8 '17 at 6:02
  • @YLearn that's not the case with the iPhone at least - it is definitely an Ad-Hoc/IBSS-based network - you can tell this because on a Mac at least, the icon representing the network looks like a chain link rather than the radial pattern used to indicate AP/Infrastructure-style networks. But yes you are right on the terminology reference in the spec. The OP wasn't clear about which "Ad-Hoc" networks they were talking about. – Benjamin Dale Nov 8 '17 at 7:35
  • Hmm, interesting. I will have to check that out sometime to see for myself. I had thought Apple used the radio in AP mode. Thanks for pointing that out. – YLearn Nov 9 '17 at 0:47
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Wireless Sensor Network (WSN) and Ad hoc Network differ in one important factor: Infrastructure-based vs Infrastructure-less. In WSN, network is managed by a base station such as these antenna around us that receive our data and phone calls.

The previous is based on definitions that may be a bit lacking. Simply stated, a WSN is neither infrastructure based nor infrastructure-less.

A WSN is simply a network of sensors that have some means of communicating data. The method of communication may be 802.11, Bluetooth, Zigbee or any of dozens of standard wireless communications methods (or a much larger number of proprietary ones). The mode of operation with the sensor network can also be of any type, whether that is some sort of infrastructure, ad hoc, or mesh topology. They may use some sort of base station/gateway, connect to a traditional network directly or connect directly to some sort of data collection point.

However, I don't understand how Ad hoc is really managed (At least I don't see its application in my daily life). Can someone explain how Ad hoc is managed? Special type of base station maybe!

An ad hoc network is simply a network where two STAs connect directly to communicate. If you have three STAs in close proximity, each STA will make separate connections to each of the other two STAs. This continues to be true as you have more STAs; five STAs in close proximity would each need to manage four connections (one to each other STA), 10 STAs means 9 connections per STA, and so on.

Communication in an ad hoc network only occurs directly between two connected STAs. Unless someone runs another process on the ad hoc STAs, there is no means of forwarding or passing along data intended for another destination than the connected STA.

I'm interested in the differences between Ad hoc and Managed mode as well. I've read some people say their card works better in managed....[snip]

This is from the comment included in the bounty from another user. While the bounty did bring this back up for attention, what the OP asked and what the user placing the bounty is asking are two different questions. This comment is about the modes of operation that can be configured for an 802.11 client, it does not relate to the general nature of the OP question about WSN and ad hoc networks and really should be asked as a separate question.

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