# Lets understand the most basic CN technically!

At the limits of the internet: Technology options for community networks1
https://www.apc.org/sites/default/files/2018_community_networks.pdf

https://www.apc.org/sites/default/files/APCHandbookWeb_EN_0.pdf
https://www.itu.int/dms_pub/itu-d/opb/tnd/D-TND-01-2020-PDF-E.pdf
https://www.internetsociety.org/wp-content/uploads/2021/04/Telecommunications-Reclaimed-HandsOn-Guide-to-Networking-Communities_EN.pdf

***Share the most basic cn***

Consider you have a phone and your sibling who lives in the same house as you have a phone. Suppose you have to send a file to their phone, you might remember using bluetooth for the same purpose or using nfc? I remember sending songs to my friends phone using bluetooth for hours. That’s the trouble with bluetooth: small range and slow speed. However, you don’t require a license to use it. In today’s world we’ll probably just send a whatsapp message. [write about the hops over the net]. But the question is how else can we communicate between two phones and not send that message all over the world…we’re sitting right next to each other. Here our phone acts as a nodes, end devices.

One hop between our phones through router. The same we use to connect to a wifi. What essentially a router does is that it redirects the messages to our phones. Now not just two devices but multiple devices can be connected to a router. All our smartphones, laptops can connect to a wifi router…it helps us connect wirelessly. Even though hardware wise we are sorted we need an application to send messages from. Here comes in the role of a server where we can deploy our own application, store files, xyz…next cloud and all..decentralised apps would help. These could follow various instructions on how to deliver messages this would be the protocols: _____. No that we are connected to all the devices in our home what if we wanted say hi you our neighbourbour who lives right across the street?

Here comes the role of mesh-ing…where two routers interact with each other. We could connect them through cables and that is how earlier our internet service providers would do…they would connect routers through cables over trees and electrical poles but that became tricky due to faulty poles and inscalable. Mesh is a protocol again that helps two routers talk to each other. Usually routers have two bands 2.4 ghz and 5 ghz : one for meshing and another as access points for our phone to connect. [But usually most of the commercial routers make it difficult for us to mesh and put passwords etc.] Libre routers are open hardware routers which come in handy here who can work for distances less than a km.

If we want larger distances to be covered then we need point to point radios. Usually they are ubiquity power beams which work for upt0 20 km . there job is to connect any two points wirelessly. Now if this is connected to the backhaul the whole network formed can also be joined together to the internet. And wohoo!

notes:
its role is to redistribute and route traffic within the network

Communicate between two phones

Bluetooth se possible, small range slow speed, no license
More people bigger range: home router
Smartphones and laptops : bounces to all over the world

Wlan and lan: [wan: backhaul ] internet uplink is a challenge

Message locally: decentralised apps

Run your own server: nextcloud, matrix

Now, we want to have for village

Dual band: one for meshing 5 ghz
One forr access points: devices connect to 2.4 ghz

Repeaters

mesh : router to router links

Cable cant lay over, maintenance tricky, electric poles are falling off, trees, lossless…wifi router relaxation of spectrum and owning devices…

Libre router : detachable antennas, less than a km, open hardware

Distance beyond that then mesh is not effective

Point to point radios: parabolic; ubiquity power beams and all
Only job link two point wirelessly [10km -20km]
For backhaul link.