Sophos Mesh Network

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You can use access points to create mesh networks.

Sophos Network Agent
Sophos Mesh Network

Using an AP as a mesh client with 5 GHz effectively reduces the maximum throughput by 50% per hop, because all data sent to the AP needs to be forwarded to the other AP, taking up additional airtime. Therefore we recommend to set the root AP to 5 GHz and the clients to 2.4 GHz. When an AP boots which is configured to use the mesh network, it tries to connect via cable to the service. If this does not work, it turns into a repeater AP and scans if the mesh network is visible. If yes, it will join the mesh network as a client. The access points realize by themselves if they are root, repeater (mesh) or bridge access points in the network.

Deployment possibilities

Mesh Networking Set up mesh networks in 2.4 GHz and 5 GHz bands with ease. Sophos wireless access points can also be set up as repeaters or bridges to extend Wi-Fi coverage in hard-to-wire areas. Configuration the Sophos UTM is easy in 12 steps. This perform basic setup for a computer in LAN go out internet through UTM. Important Step noted: Setup WAN interface and Default Gateway (step 6). Compare Sophos UTM vs Ubiquiti Networks UniFi. 112 verified user reviews and ratings of features, pros, cons, pricing, support and more. Outdoor Mesh AP's with an.

Mesh mode enables you to have multiple access points where one is the root AP and the others are repeater APs, called mesh APs. There can be multiple root APs. Mesh APs can broadcast the SSID from the root AP to cover a larger area without cabeling each AP.

A mesh network can also be used to bridge Ethernet networks without laying cables. To run a wireless bridge you have to plug your second Ethernet segment into the Ethernet interface of the mesh access point. The first Ethernet segment is the one on which the root access point connects to the service.

Good to know

There are some things you should know about mesh networks:

At least one access point needs a LAN connection.
Mesh access points need to be on the same channel to make a communication possible.
Avoid using dynamic channel selection as after a reboot the channels of the APs may differ.
The mesh network may need up to five minutes to be available after configuration.
You can have only one mesh SSID.
A mesh network can be realized only with Sophos access points.
For setting up a mesh network you need to create a new SSID.
There is no automatic takeover of the root AP. The decision to connect to mesh happens during the boot.

Diagram showing a possible configuration for a wired-wireless mesh network, connected upstream via a VSAT link (click to enlarge)

A wireless mesh network (WMN) is a communications network made up of radionodes organized in a meshtopology. It can also be a form of wireless ad hoc network.^[1]

A mesh refers to rich interconnection among devices or nodes. Wireless mesh networks often consist of mesh clients, mesh routers and gateways. Mobility of nodes is less frequent. If nodes constantly or frequently move, the mesh spends more time updating routes than delivering data. In a wireless mesh network, topology tends to be more static, so that routescomputation can converge and delivery of data to their destinations can occur. Hence, this is a low-mobility centralized form of wireless ad hoc network. Also, because it sometimes relies on static nodes to act as gateways, it is not a truly all-wireless ad hoc network.^{[citation needed]}

Mesh clients are often laptops, cell phones, and other wireless devices. Mesh routers forward traffic to and from the gateways, which may, but need not, be connected to the Internet. The coverage area of all radio nodes working as a single network is sometimes called a mesh cloud. Access to this mesh cloud depends on the radio nodes working together to create a radio network. A mesh network is reliable and offers redundancy. When one node can no longer operate, the rest of the nodes can still communicate with each other, directly or through one or more intermediate nodes. Wireless mesh networks can self form and self heal. Wireless mesh networks work with different wireless technologies including 802.11, 802.15, 802.16, cellular technologies and need not be restricted to any one technology or protocol.

Features[edit]

Architecture[edit]

Wireless mesh architecture is a first step towards providing cost effective and low mobility over a specific coverage area. Wireless mesh infrastructure is, in effect, a network of routers minus the cabling between nodes. It is built of peer radio devices that do not have to be cabled to a wired port like traditional WLANaccess points (AP) do. Mesh infrastructure carries data over large distances by splitting the distance into a series of short hops. Intermediate nodes not only boost the signal, but cooperatively pass data from point A to point B by making forwarding decisions based on their knowledge of the network, i.e. perform routing by first deriving the topology of the network.

Wireless mesh networks is a relatively 'stable-topology' network except for the occasional failure of nodes or addition of new nodes. The path of traffic, being aggregated from a large number of end users, changes infrequently. Practically all the traffic in an infrastructure mesh network is either forwarded to or from a gateway, while in wireless ad hoc networks or client mesh networks the traffic flows between arbitrary pairs of nodes.^[2]

If rate of mobility among nodes are high, i.e., link breaks happen frequently, wireless mesh networks start to break down and have low communication performance.^[3]

Management[edit]

This type of infrastructure can be decentralized (with no central server) or centrally managed (with a central server).^[4] Both are relatively inexpensive, and can be very reliable and resilient, as each node needs only transmit as far as the next node. Nodes act as routers to transmit data from nearby nodes to peers that are too far away to reach in a single hop, resulting in a network that can span larger distances. The topology of a mesh network must be relatively stable, i.e., not too much mobility. If one node drops out of the network, due to hardware failure or any other reason, its neighbors can quickly find another route using a routing protocol.

Applications[edit]

Mesh networks may involve either fixed or mobile devices. The solutions are as diverse as communication needs, for example in difficult environments such as emergency situations, tunnels, oil rigs, battlefield surveillance, high-speed mobile-video applications on board public transport, real-time racing-car telemetry, or self-organizing Internet access for communities.^[5] An important possible application for wireless mesh networks is VoIP. By using a quality of service scheme, the wireless mesh may support routing local telephone calls through the mesh. Most applications in wireless mesh networks are similar to those in wireless ad hoc networks.

Some current applications:

U.S. military forces are now using wireless mesh networking to connect their computers, mainly ruggedized laptops, in field operations.^{[citation needed]}
Electric smart meters now being deployed on residences, transfer their readings from one to another and eventually to the central office for billing, without the need for human meter readers or the need to connect the meters with cables.^[6]
The laptops in the One Laptop per Child program use wireless mesh networking to enable students to exchange files and get on the Internet even though they lack wired or cell phone or other physical connections in their area.
Google Home, Google Wi-Fi, and Google OnHub all support Wi-Fi mesh (i.e., Wi-Fi ad hoc) networking.^[7] Several manufacturers of Wi-Fi routers began offering mesh routers for home use in the mid-2010s.^[8]
The 66-satellite Iridium constellation operates as a mesh network, with wireless links between adjacent satellites. Calls between two satellite phones are routed through the mesh, from one satellite to another across the constellation, without having to go through an earth station. This makes for a smaller travel distance for the signal, reducing latency, and also allows for the constellation to operate with far fewer earth stations than would be required for 66 traditional communications satellites.

Operation[edit]

The principle is similar to the way packets travel around the wired Internet—data hops from one device to another until it eventually reaches its destination. Dynamic routing algorithms implemented in each device allow this to happen. To implement such dynamic routing protocols, each device needs to communicate routing information to other devices in the network. Each device then determines what to do with the data it receives – either pass it on to the next device or keep it, depending on the protocol. The routing algorithm used should attempt to always ensure that the data takes the most appropriate (fastest) route to its destination.

Multi-radio mesh[edit]

Multi-radio mesh refers to having different radios operating at different frequencies to interconnect nodes in a mesh. This means there is a unique frequency used for each wireless hop and thus a dedicated CSMAcollision domain. Withmore radio bands, communication throughput is likely to increase as a result of more availablecommunication channels. This is similar to providing dual or multiple radio paths to transmitand receive data.

Research topics[edit]

One of the more often cited papers on Wireless Mesh Networks identified the following areas as open research problems in 2005

New modulation scheme
- To achieve higher transmission rate requires new wideband transmission schemes other than OFDM and UWB.
Advanced antenna processing
- Advanced antenna processing including directional, smart and multiple antenna technologies is further investigated, since their complexity and cost are still too high for wide commercialization.
Flexible spectrum management
- Tremendous efforts on research of frequency-agile techniques are being performed for increased efficiency.
Cross-layer optimization
- Cross-layer research is a popular current research topic where information is shared between different communications layers to increase the knowledge and current state of the network. This could facilitate development of new and more efficient protocols. A joint protocol that addresses various design problems—routing, scheduling, channel assignment etc.—can achieve higher performance since these problems are strongly co-related.^[9] Note that careless cross-layer design can lead to code that is difficult to maintain and extend.^[10]
Software-defined wireless networking
- Centralized, distributed, or hybrid? - In^[11] a new SDN architecture for WDNs is explored that eliminates the need for multi-hop flooding of route information and therefore enables WDNs to easily expand. The key idea is to split network control and data forwarding by using two separate frequency bands. The forwarding nodes and the SDN controller exchange link-state information and other network control signaling in one of the bands, while actual data forwarding takes place in the other band.
Security
- A WMN can be seen as a group of nodes (clients or routers) that cooperate to provide connectivity. Such an open architecture, where clients serve as routers to forward data packets, is exposed to many types of attacks that can interrupt the whole network and cause denial of service (DoS) or Distributed Denial of Service (DDoS).^[12]

Protocols[edit]

Routing protocols[edit]

There are more than 70 competing schemes for routing packets across mesh networks. Some of these include:

Associativity-Based Routing (ABR)^[1]
AODV (Ad hoc On-Demand Distance Vector)
B.A.T.M.A.N. (Better Approach To Mobile Adhoc Networking)
Babel (protocol) (a distance-vector routing protocol for IPv6 and IPv4 with fast convergence properties)
Dynamic NIx-Vector Routing|DNVR^[13]
DSDV (Destination-Sequenced Distance-Vector Routing)
DSR (Dynamic Source Routing)
HSLS (Hazy-Sighted Link State)
HWMP (Hybrid Wireless Mesh Protocol, the default mandatory routing protocol of IEEE 802.11s)
Infrastructure Wireless Mesh Protocol (IWMP) for Infrastructure Mesh Networks by GRECO UFPB-Brazil^[14]
OLSR (Optimized Link State Routing protocol)
OORP (OrderOne Routing Protocol) (OrderOne Networks Routing Protocol)
OSPF (Open Shortest Path First Routing)
Routing Protocol for Low-Power and Lossy Networks (IETF ROLL RPL protocol, RFC6550)
PWRP (Predictive Wireless Routing Protocol)^[15]
TORA (Temporally-Ordered Routing Algorithm)
ZRP (Zone Routing Protocol)

The IEEE has developed a set of standards under the title 802.11s.

A less thorough list can be found at Ad hoc routing protocol list.

Autoconfiguration protocols[edit]

Wikimedia Commons has media related to Mesh network.

Standard autoconfiguration protocols, such as DHCP or IPv6 stateless autoconfiguration may be used over mesh networks.

Mesh network specific autoconfiguration protocols include:

Ad Hoc Configuration Protocol (AHCP)
Proactive Autoconfiguration (Proactive Autoconfiguration Protocol)
Dynamic WMN Configuration Protocol (DWCP)

Communities and providers[edit]

Freifunk (DE) / FunkFeuer (AT) / OpenWireless (CH)
Ninux (IT)

References[edit]

^ ^a^bChai Keong Toh Ad Hoc Mobile Wireless Networks, Prentice Hall Publishers, 2002. ISBN978-0-13-007817-9
^J. Jun, M.L. Sichitiu, 'The nominal capacity of wireless mesh networks', in IEEE Wireless Communications, vol 10, 5 pp 8-14. October 2003
^Wireless Communications, Networking and Applications: Proceedings of WCNA 2014.
^Cheng, Shin-Ming; Lin, Phone; Huang, Di-Wei; Yang, Shun-Ren (July 2006). 'A study on distributed/centralized scheduling for wireless mesh network'. IWCMC '06: Proceedings of the 2006 International Conference on Wireless Communications and Mobile Computing: 599. doi:10.1145/1143549.1143668. ISBN1595933069. S2CID8584989.
^Beyer, Dave; Vestrich, Mark; Garcia-Luna-Aceves, Jose (1999). 'The Rooftop Community Network: Free High-Speed Network Access for Communities'. In Hurley, D.; Keller, J. (eds.). The First 100 Feet. MIT Press. pp. 75–91. ISBN0-262-58160-4.
^'ZigBee.org Smart Energy Overview'.
^Hildenbrand, Jerry (13 October 2016). 'How Wi-Fi mesh networks work'. Android Central.
^Fleishman, Glenn (May 5, 2020). 'Wireless mesh networks: Everything you need to know'. PCWorld. Retrieved 2018-10-09.
^Pathak, P. H.; Dutta, R. (2011). 'A Survey of Network Design Problems and Joint Design Approaches in Wireless Mesh Networks'. IEEE Communications Surveys & Tutorials. 13 (3): 396–428. doi:10.1109/SURV.2011.060710.00062. S2CID206583549.
^Kawadia, V.; Kumar, P.R. (2005). 'A cautionary perspective on cross-layer design'. IEEE Wireless Communications. 12 (1): 3–11. doi:10.1109/MWC.2005.1404568. ISSN1536-1284. S2CID1303663.
^Abolhasan, Mehran; Lipman, Justin; Ni, Wei; Hagelstein, Brett (July 2015). 'Software-defined wireless networking: centralized, distributed, or hybrid?'. IEEE Network. 29 (4): 32–38. doi:10.1109/MNET.2015.7166188. ISSN0890-8044. S2CID1133260.
^Alanazi, Shaker; Saleem, Kashif; Al-Muhtadi, Jalal; Derhab, Abdelouahid (2016). 'Analysis of Denial of Service Impact on Data Routing in Mobile eHealth Wireless Mesh Network'. Mobile Information Systems. 2016: 1–19. doi:10.1155/2016/4853924. ISSN1574-017X.
^Lee, Y. J.; Riley, G. F. (March 2005). 'Dynamic nix-vector routing for mobile ad hoc networks'. IEEE Wireless Communications and Networking Conference, 2005. 4: 1995–2001 Vol. 4. doi:10.1109/WCNC.2005.1424825. ISBN0-7803-8966-2. S2CID2648870.
^Porto, D. C. F.; Cavalcanti, G.; Elias, G. (1 April 2009). 'A Layered Routing Architecture for Infrastructure Wireless Mesh Networks'. Fifth International Conference on Networking and Services, 2009. ICNS '09: 366–369. doi:10.1109/ICNS.2009.91. ISBN978-1-4244-3688-0. S2CID16444897.
^'TropOS is field-proven for creating scalable network architecture - TropOS Technology | Unified Network Management (Wireless Mesh Network Communication Solutions | ABB Wireless)'. new.abb.com. Retrieved 2019-12-19.

Sophos Network Agent

External links[edit]

How Wireless Mesh Networks Work at HowStuffWorks
First, Second and Third Generation Mesh Architectures History and evolution of Mesh Networking Architectures
Miners Give a Nod to Nodes Article reprint from Mission Critical Magazine on Mesh in underground mining
IET From hotspots to blankets
Akyildiz, Ian. F.; Xudong Wang (September 2005). 'A Survey on Wireless Mesh Networks'. IEEE Communications Magazine. 43 (9): s23–s30. CiteSeerX10.1.1.133.5446. doi:10.1109/MCOM.2005.1509968. S2CID815769.
Mesh Networks Research Group Projects and tutorials' compilation related to the Wireless Mesh Networks
Advantages and disadvantages of wireless mesh RF Wireless world