IEEE 802.11s Wi-Fi Mesh for the smallest part one

Now Mesh networks are distributed throughout the world, and during the construction of networks, you can choose between Mesh protocols, there is BATMAN adv checked by time, there is a new and actively developed cjdns, and there is an “official” one - IEEE 802.11s



About 802.11s there is very little information in runet, so let's talk about how it works, why it is needed and what it does.

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Content:

• Why do you need
• What can
• What modes of operation does it support?
• Comparison with BATMAN / cjdns
• Why is good, and why not so

Why do you need

In the world there is a trend on the Mesh network, some of them are used in the local manifestation and someone in the global.



The simplest example of local use is in hotels, cafes and restaurants.

When you launch Mesh networks in a commercial structure, we get all the advantages of managed Mesh networks.



1) No need to pull your cable to each access point

2) Dots are automatically configured on the network

3) The loss of one point leads to rebuilding routing with minimal degradation of service for subscribers



But there are global, not managed networks - there are a huge number of them in the world en.wikipedia.org/wiki/List_of_wireless_community_networks_by_region

Obviously, in global networks it makes no sense to use managed protocols, and indeed, it is desirable that the network itself would resolve conflicts and configure itself.

What can

IEEE 802.11s Allows you to create managed networks, in theory, you can create and not managed, but it is not intended for this.



The protocol is engaged in updating the routing tables within the entire network, works at the L2 level using the OSI model, but you have to either configure the IP addresses on each access point yourself, or use the old DHCP services.



Also responsible for the search and interaction with neighboring points, the integration of new points in the Mesh network.



Mesh network can work with a common password and be closed or without encryption (as in a conventional Wi-Fi network) there is only up to the access point (when using a network with a password) there is no tunnel end-to-end encryption - no. NSA FSB Approves.



To connect to a network based on IEEE 802.11s, you will need:

• Equipment that supports IEEE 802.11s
• Mesh network ID
• Prescribed IP address on TD or configured DHCP in segment

If the network is password protected, the network password is added to the requirements.

What modes of operation does it support?

Network topology:





Mesh network topology:





Mesh Point (MP) - Full member of the Mesh network, interacts with its Mesh protocol neighbors

Mesh AP (MAP) - Allows you to connect STA to Mesh AP

Mesh Portal (MPP) - Bridge to another network, such as wired

Station (STA) - Output nodes from the Mesh network for connecting regular non-Mesh clients

Comparison with BATMAN / cjdns

802.11s differs from BATMAN / cjdns in that for it there is currently no free implementation for UNIX, but here they are trying to make it



In addition, BATMAN adv has already been tested for many years, showing its stability, and of course, iron support should not be forgotten.

Compared to cjdns, the protocol has the same disadvantages as everyone else (except netsukuku)

• No end-to-end encryption
• Inability to merge mesh segments with tunnels via the Internet
• No decentralized generation of IP addresses

Why is good, and why not so

Thus, it turns out that the 802.11s protocol, however, like Batman, is excellent for building managed mesh networks , while self-organizing ones should be given to other technologies - ntsukuku / cjdns.



If publications on the topic 802.11s are interesting for you, next time we will look at you:

1) 802.11s Routing

2) Configure centralized Internet access from an 802.11s mesh network

3) Combining 2 Lan networks and 1 mesh into one common





PS The results of the registration on the map (in the project jdns), why it is needed and what's next - will be a little later