Hi
I've heard a lot about AREDN but always had trouble to understand what exactly it is from a technical standpoint. In my immediate environment there's quite some knowledge on how to use AREDN but not about what exactly it is or how it works.
So far I came to the conclusion that the name AREDN stands for two different things:
For the second question: Can someone explain to me what the distinction (apart from a UI oriented towards the projects goals) to IEEE802.11s is (if any)?
This is my first post here. I hope I didn't do anything wrong! If I did I'm eager to learn!
73, Mike/HB9AKM
I've heard a lot about AREDN but always had trouble to understand what exactly it is from a technical standpoint. In my immediate environment there's quite some knowledge on how to use AREDN but not about what exactly it is or how it works.
So far I came to the conclusion that the name AREDN stands for two different things:
- The AREDN project with it's abstract goals.
- The AREDN firmware, solving a technical problem towards one or more of those goals.
For the second question: Can someone explain to me what the distinction (apart from a UI oriented towards the projects goals) to IEEE802.11s is (if any)?
- Couldn't the same be achieved using IEEE802.11s on our frequencies? Or is this what the AREDN firmware does/is?
- What are the technical reasons to prefer AREDN over IEEE802.11s for the goals of the AREDN project? Or is this more of a "how it developed" situation?
This is my first post here. I hope I didn't do anything wrong! If I did I'm eager to learn!
73, Mike/HB9AKM
Short reply:
AREDN does not support 802.11s and, thus, may not relate to most of your post.
Long reply:
Although the word 'mesh' is used extremely frequently in discussions of AREDN,
the 'mesh' topology is not part of the firmware. One can build a 'mesh topology'
network using routers running AREDNMESH.ORG firmware. One can as easily
build Point-to-multipoint ('star' or 'hub and spoke') and point-to-point topologies.
"So far I came to the conclusion that the name AREDN stands for two different things: "
I am baffled by that statement.
I feel it is intuitively obvious to the most casual of observer that AREDN stands for:
Amateur Radio Emergency Data Network.
AREDN firmware's primary purpose is for building networks using
802.11a,b,g,n,ac routers that have underlying OpenWRT code and
whose wireless chipset can be made to operate on Amateur Radio frequencies.
73, Chuck
Thanks for your reply and your answers! I'm having problems asking these questions in my first language (German), so some additional barrier is to be expected when asking them in English. So I guess an iterative approach is best ;-)
I am aware that AREDN is an abbreviation standing for "Amateur Radio Emergency Data Network". My question is about the terminology when talking about the different parts (the actual physical network, the organization, the community, the firmware, ...). If you're talking about "AREDN", which part is meant? What terminology is used to refer to the parts of the whole? I hope this makes it more clear what I'm trying to ask.
About the second question: So far I assumed that the AREDN firmware implements its own layer 2 protocol(s) and therefore is not compatible with any of the IEEE802.11 (WiFi) standards. My question is whether this assumption is correct and if so, what the reasons were / advantages are to create a new layer 2 protocol. If the assumption is incorrect I would like to know what standards are used and what the exact difference to 802.11 is (if any).
You mentioned OpenWRT. Is the AREDN firmware based on OpenWRT or is compatibility with OpenWRT simply a good indicator that hardware also works using the AREDN firmware?
You mentioned that "the 'mesh' topology is not part of the firmware". Whenever AREDN was explained or shown to it was always made a point that the nodes organize themselves which was called "meshing". By that I understood that some automatic routing is done that avoids loops, finds the shortest/best path and so on. If this were the case I guess this needs to be part of the firmware. Or is the "mesh" part done by layer 3 switches the wireless APs are connected to?
These questions might seem a bit pedantic. But if I want to explain this to others I want to be sure not to tell them something wrong. I need to understand how it works in order to explain what it is (at least to some degree). This applies to both of my questions.Thanks in advance for any further insights and the patience to answer my questions!
73, Mike
I suggest you contact KB9BLA
https://www.arednmesh.org/user/5286/contact
and/or those on this map:
The basic support for node to multiple node communication is a mode supported by the radio hardware (chip). That mode is called "ad hoc" and is defined in the 802.11 specifications as an Independant Basic Service Set (IBSS). In this mode there is no authentication to an Access Point and all members must be set to the same SSID. With more than 2 members, such a network IS a mesh.
But the hardware "ad hoc" mode does no sophisticated routing. It can filter packets by MAC address but that's about it. To make better use of "ad hoc" mode as a mesh network, especially "multi-hop" paths, some higher level (network layer 3) functions are required to make packet routing decisions based on configuration, signal conditions and data traffic conditions. AREDN firmware adds this layer of extra function.
802.11s is an extension to the IEEE Wi-Fi standards that aims to perform the class of decision-making that the AREND firmware does. AFAIK consumer hardware implementing 802.11s is relatively new, expensive and may exist in mostly (only?) radio chips that don't allow operating on ham only frequencies.
/welcomes any corrections
While I don't have the precise technical answers perhaps I can help a small amount. AREDN is a system, a template, a process. We use AREDN firmware to alter commercially available equipment to make regional networks. While there are the links via supernodes, there is no ONE AREDN system, there are many networks that use the protocols.
The firmware is based on OpenWRT so this limits the devices that can have firmware developed.
The entire concept of AREDN is to use a part of the FCC rules that allow for experimentation by licensed amateurs, so we can develop uses for equipment that consumers should not use. However, amatuer radio operators may not encrypt their transmissions by FCC rules, so certain wireless standards are observed by the developers so we are compliant with the law. This may limit the technical standards you ask about.
Lastly, the routing tables are updated ad hoc and the actual network topology can be point to point, hub and spoke, or somewhat mesh like. It's good to have more than one possible connection (more like a mesh) so a station is less likely to lose connection in a true emergency. But if you look at the rf maps, some places look different than other places. It is what it is.
73, Ed