Wireless mesh-network or Tenda Nova
Recently, we were approached by representatives of Tenda with a proposal to describe their new development - a wireless mesh-network built on the basis of the Tenda Nova equipment line. No, of course, the very idea of mesh-networks is not new. Moreover, in the modern world, it is no longer necessary to reinvent the wheel; there are a number of solutions and standards, you just need to create equipment with the support of one of them. As a device for consideration, we were offered the Tenda Nova MW6-2 model, which allows us to build a mesh-network based on the IEEE 802.11s standard. But do not be afraid, users do not need to understand all the details of the standard - the Tenda Nova mesh system works out of the box.
Many of our readers, for sure, have already come across mesh-networks, for example, we mentioned support for such networks by other vendors. Let's try to dig a little deeper and deal with some details of the functioning of mesh networks in the implementation of Tenda.
Modern Wi-Fi routers provide a large coverage area but it can be difficult to cover rooms with thick walls, reinforced concrete structures and other obstacles that prevent the spread of Wi-Fi signal. There are “dead zones”. Traditionally, the problem was solved by installing repeaters (extenders) or additional access points in such places but this approach is not without flaws:
- repeaters, although they help to enhance the Wi-Fi signal but usually half the bandwidth is lost;
- access points provide more bandwidth but this requires a wired connection to the rest of the network;
- a new network is created (with its SSID and password); thus, changing your location, you need to reconnect by entering a password.
Everything is simplified if you use a Wi-Fi mesh system.
We will consider wireless mesh-networks based on the MW6 kit. Different MW6 kits are available for order, including one, two or three nodes; before purchasing, you must make sure that the exact kit is in order.
Each node of the wireless-mesh network is a plastic cube, similar to a simplified Rubik's cube, which cells are white. Devices with such a body do not need to be hidden, the design is very pleasant. Nova units use internal antennas, making it easy to fit into almost any interior. The block dimensions are 100x100x100 mm with a mass of just 410 g.
On the top panel there is a small LED that displays the status of the device and its connection to the network.
The top panel and all side panels do not carry any connectors; the bottom panel of the unit is used for connection, on which, in addition to the ventilation grate and stickers with brief information, there are two Gigabit Ethernet interfaces and a DC-in port for power supply. There are also four rubber feet and a recessed Reset button. The purpose of each wired network interface is marked on the label; however, the separation between LAN and WAN is relevant only for the “main” node, all other blocks use both Gigabit Ethernet ports as LAN interfaces. These wired interfaces can be used to connect a TV or game console in situations where there is no possibility to carry a dedicated Ethernet cable for them.
Each unit for its work requires an external power source (supplied) with the following characteristics: 12V and 1.5A.
Now let's look inside the case and find out which elemental base the model MW6 is built on. The electronics of the model under consideration is represented by two textolite boards, one of which houses network ports and a power input connector. In fact, this board is an adapter, since there is no significant silicon on it. SoC Realtek RTL8197FS, operating at a frequency of 1 GHz, as well as 128 MBytes RAM and a 16 MBytes flash drive are located on the main board. In addition, the Realtek RTL8363NB switch is located on the main board.
This concludes a cursory review of the hardware platform and proceeds to the brief basics of the functioning of mesh networks.
Wireless mesh-networks, that is, networks with a mesh topology, are a promising and constantly evolving area. With the use of mesh networks, the dream of seamless roaming in Wi-Fi networks can become a reality today. Wireless mesh networks can be easily and efficiently, and most importantly without laying additional wires, used to connect entire cities to the global network. Of course, in this review we do not aim at such a scale but the technologies used in the Tenda MW6 are the same.
Consider the classic concepts and protocols used in mesh-networks.
Let's first define the terminology. In conventional wireless networks based on the IEEE 802.11 standards, two types of devices are defined: STA - end stations (subscriber devices) and access points (AP - Access Points). Access points are also connected to networks of other technologies, for example, Ethernet. Client stations can communicate only with access points. For IEEE 802.11s wireless mesh-networks, a special type of device is defined - mesh points (MP - Mesh Points) that interact with each other and support mesh services. Mesh points can be combined with classic access points. Such a hybrid is called MAP - Mesh Access Point. MPP - Mesh Point Portal is responsible for the connection of the mesh-network with the "outside" world.
The mesh points independently choose the most optimal route using a variety of dynamic routing protocols. The dynamic routing protocols in a mesh network differ from those known to us over wired networks (for example, OSPF, RIP or BGP) but the basic principles are very similar.
The main advantage of wireless mesh networks is that they are actually wireless. Ordinary large Wi-Fi networks require a basic wired network for their work, while wireless channels are used for communication between points in mesh networks. Only one point must be connected to the wired network. It’s probably worth noting that the Tenda Nova series devices allow using both wireless and wired channels (if available) to communicate with each other, that is, the mesh topology is formed regardless of the method of communication between nodes at the physical level.
However, let's go back to the routing protocols used in wireless self-organizing networks. One of such protocols is AODV - Ad Hoc On-Demand Distance Vector, that is, the distance-vector protocol with the establishment of communication on demand. The essence of his work is that the calculation of the path is made at the request of the sender, that is, when there is user traffic for transmission over the network. The figure below shows the distribution directions for RREQ requests (red arrows) and RREP responses (green). The calculated routes are saved as long as they are necessary for the sender. AODV is suitable for both unicast and multicast traffic. A more detailed description of the protocol can be found in RFC 3561.
DSR - Dynamic Source Routing, in many respects similar to AODV, however DSR performs source routing. In its work, DSR relies on two mechanisms: Route Discovery and Route Maintenance. The first is responsible for finding the optimal path, the second ensures its maintenance in the event of changing network parameters. Source routing relieves intermediate mesh points from maintaining the routing table, since the entire route is defined by the point sending the data to the network. The DSR protocol is described in RFC 4728.
DSDV - Destination-Sequenced Distance-Vector Routing is based on the Bellman-Ford algorithm. Each entry in the routing table has a sequence number, which marks the accessible (even sequence number) and inaccessible (odd number) networks. For its work, it requires periodic distribution of route updates, which is attributed to its shortcomings, since even during network downtime, service information continues to be transmitted. The advantage in this case will be a faster readiness of the route before use.
TORA - Temporally Ordered Routing Algorithm uses a Directed Acyclic Graph (DAG) with a root at the destination. In this graph, there are no directed cycles, although the existence of parallel paths is allowed. In essence, a DAG is an association of trees (forest).
What is implemented in a series of devices Tenda Nova? Wi-Fi mesh-system consists of several network components - blocks. Directly to the modem or provider connects the main unit, and the rest (satellites) are located throughout the house or apartment. The satellites themselves (automatically) communicate with the main unit and with each other, forming a single wireless network that has one common SSID and password. Thanks to mesh technology, a system delivers a powerful signal to a user device in a lossless fashion. Like ordinary dual-band routers, wireless mesh systems operate on standard 2.4 GHz and 5 GHz frequencies.
Inside the wireless transport network, Mesh Points use their own routing protocol, which incorporates the best of the standard protocols listed above. The implementation of the routing and forwarding of traffic over the network directly affects the efficiency of the mesh networks and the loading of transmission channels, that is, the performance of the entire network as a whole. The routing protocol uses more complex metrics when choosing the best path, and not just the number of poins along the traffic path. Thus, mesh networks are resistant to failures of wireless channels, quickly select the data transfer alternate path to avoid long service interruptions, support traffic management services and load balancing.
The number of points used in such a mesh network will depend on the number and activity of wireless clients, as well as on the areas where it is necessary to ensure stable operation of the wireless network. The most common scenarios are:
- spacious city apartment - 2 blocks;
- medium or large country house, or a small office - from 3 blocks;
- large suburban area or office - up to 9 devices located in different rooms.
This concludes a brief study of the fundamentals of the functioning of mesh networks and proceeds to consider the management interface of the Tenda MW6 model.
Although the Tenda Nova range of devices is ready to work with the minimum settings, you still have to change some configuration parameters. There is neither the usual web interface, nor the command line; all management is performed using a specialized utility Tenda WiFi, installed on the smartphone. We have to admit, we were somewhat discouraged. Yes, in our opinion, the ability to control devices using the utility is an excellent option but as an addition to the web interface. Consider the possibilities for setting up a home network provided by the Tenda WiFi utility.
When you first start the application Tenda WiFi determines the wireless network to which the smartphone is connected. For further work, it is necessary that the connection be made to a wireless network organized by MW6.
In order to proceed with the initial setup, you need to connect Tenda Nova to WAN/Internet. Immediately it should be noted that all the devices in the kit are the same, that is, you can connect the provider to any of the units.
Several types of connection to providers are supported: static and dynamic (DHCP) IP address, PPPoE, as well as tunnel connections that are so popular in the post-Soviet space using PPTP and L2TP protocols.
Immediately it is worth noting that the list of supported connection types depends on the interface language of the smartphone. The TendaWiFi application determines the interface language and it displays connection options.
The next step is to set up the SSID and password. The network name and password are the same for all nodes and both ranges. Also, it should be noted that the Tenda Nova always uses strictly fixed wireless channels: No. 6 in the 2.4 GHz band and No. 40 in the 5 GHz band which was done to improve the stability of the wireless network. But, we must admit, we are somewhat surprised by this decision. Also, you can not change the encryption type - only WPA2 PSK. True, in this case we have no objections.
It is time to add the rest of the Nova devices to the newly created mesh network. Tenda Nova mesh network nodes can be connected to each other using wire or wireless channels. If there are several available links, the following preference scheme is used (in descending order): Ethernet -> Wi-Fi 5 GHz -> Wi-Fi 2.4 GHz.
After the material was already written, we discovered the appearance of an updated version of the mobile application which made it possible to add a satellite block, simply by scanning its label or typing the serial number manually.
After all the necessary devices have been added, you must specify the credentials that will be used to access the router and the mesh network.
Looking ahead, we would like to note that management can be done not only with a single smartphone, that is, it is possible to add several administrative accounts.
That’s it, initial setup of the device is complete. No additional configuration of the mesh network was required. The main screen of the Tenda WiFi application now displays all the nodes included in the mesh network and the connections between them.
For each node of the mesh network, you can view additional information, as well as specify its location.
It should be added that it is possible to combine not only equipment of the MW6 model into one mesh-network but also another, for example, MW3. That is, in fact, users can build a single network using different Tenda wireless devices. The only thing to remember is the existing limit on the maximum number of nodes in such a mesh network. Up to ten wireless devices on the network are currently supported (up to six are recommended). One MW6 device can serve 30-35 wireless clients, so a set of three cubes can serve up to 100 wireless clients. In addition to the number of simultaneously served wireless clients, the coverage area provided by the mesh network must also be considered. For example, a network with two nodes provides reliable coverage on areas up to 300 m2. While a network with three nodes already allows you to expand this area to 500 m2. But, perhaps, the main advantage will be the possibility of placing the nodes of the mesh network in the most convenient place, which will ensure the best network performance and the client devices connected to it by selecting the unit for connection that allows wireless clients to work at maximum speed.
If necessary, the network administrator can view detailed information about all connected wireless clients, as well as add devices to groups.
We decided not to stop there and consider all the other settings available to users.
There is no desire to show the password from your Wi-Fi network? No problem - create a temporary guest network.
If there is a child in the house, the Tenda NW6 wireless equipment will allow you to introduce additional rules for controlling access to the global network for devices used by the child.
Mesh network allows you to significantly expand the coverage of a wireless network. However, in the process of use, negative emotions may still appear associated with the process of reconnecting the client device between the nodes of the mesh network. Standard roaming can lead to noticeable loss of traffic, which is particularly acute during audio and video calls. To avoid these problems will help the inclusion of support for fast roaming. It is also worth noting the presence of technology MU-MIMO which allows parallel data transfer for several wireless users connected to one unit. Naturally, users connected to different Tenda Nova units could even perform parallel transmission without this option, since different units use different wireless channels, which does not lead to collisions.
Like any regular SOHO router, the Tenda MW6 allows port forwarding, providing remote users with an opportunity to connect to resources within the local network.
With appropriate support from the application, the ports of the transport protocols can be opened automatically using the UPnP.
Naturally, the address of the LAN interface can be changed. Perhaps, it is worth noting that we are talking about the address of the control device, since all other network elements receive IP addresses dynamically.
The manufacturer includes support of quality of service (QoS). However, there are no fine settings here. They may appear in the next firmware versions.
By the way, you can also update the firmware using a mobile utility. Of course, this requires a connection to the global network.
After updating the firmware, a number of new features become available to users. These include, for example, the option of intelligent assistant and high performance.
If necessary, the administrator can configure an automatic reboot of devices that provide the mesh network. The reboot is performed on certain days of the week and at the specified time.
This concludes consideration of the capabilities of the mobile application Tenda WiFi.
Since the manufacturer asked us to review mesh networks based on the Nova device line and not to do the traditional testing for us, you will not find our usual tests in this section. But we couldn’t, of course, be able to completely leave the reader without the results of measuring performance. The table below presents the main parameters of our test bench.
|MB||ASUS Maximus IX Extreme||ASUS GL753VD|
|CPU||Intel Core i7 7700K 4 GHz||Intel Core i7 7700HQ 2.8 GHz|
|RAM||DDR4-2133 Samsung 64 GByte||DDR4-2400 Kingston 32 GByte|
|Realtek PCIe GBE
|OS||Windows 7 x64 SP1||Windows 10 x64|
JPerf utility version 2.0.2 was used to generate traffic. Measurements were made for 1, 5 and 15 simultaneous TCP connections.
We decided to start by finding out the data transfer rates that will be available to wireless clients connected to both frequency bands. Measurements were made at relatively close locations of the MW6 and wireless clients (in line of sight), so the transmission speeds in real conditions can differ significantly from those measured by us.
Since the Tenda MW6 is a wireless mesh system, we decided to find out which users can count on the maximum performance of the wireless channel between the nodes of the mesh network. The measurements were performed using two wired clients connected to two neighboring nodes (primary and secondary) of the mesh network.
In conclusion, we decided to measure the time of network convergence, that is, we figured out how long the mesh network could detect changes and adapt to them. We had a Tenda MW6 kit of two devices at our disposal, so obviously, we were very limited in our testing methods. We placed both blocks in close proximity to each other and connected them with a patch cord. Since the cable connection of the blocks takes precedence over the wireless connection, the traffic between the nodes was transmitted over twisted pair. Then we physically disconnected the cable and measured the time after which the flow of traffic between the nodes would be restored, that is, it would switch to a wireless link. Mesh-system Tenda Nova adapted in about 54 seconds. In our opinion, this is a rather long convergence time, however, as it seems to us, it will be quite acceptable for most home users.
Now let's summarize.
A set of nodes for building a wireless mesh network Tenda MW6 allows you to build a stable wireless network in a country house or a large city apartment. A distinctive feature of the implementation is the readiness of the equipment to work almost out of the box, that is, with minimal settings. The nodes of the mesh network will automatically build the most optimal topology themselves, over which user data will be transmitted. The scalability of the solution, which goes far beyond the capabilities of one devices set, allows providing a wireless connection to rooms with a very large area, providing wireless clients with the possibility of smooth reconnection to another node when moving within the coverage area.
The strengths of the system include the following:
- support fast roaming (IEEE 802.11r / v);
- the ability to create a guest network;
- nice design;
- the possibility of combining a mesh-network devices of different models;
- mobile application;
- the possibility of independent operation of each of the nodes;
- easy setup;
- parental control function;
- the possibility of both wired and wireless nodes peering.
The lack of a web interface we can not call a problem or a flaw. Of course, we understand that many users have long been more comfortable with setting up equipment using a mobile application installed on a smartphone. However, in our opinion, the good old web interface would also be a popular way to manage the network. We would also like to see support for the IPv6 protocol in such devices; we very much hope that the manufacturer will soon add it.
At the time of writing this review, the best price for a set of two Tenda MW6 devices in German-speaking Europe countries, according to website Geizhals Preisvergleich, was about 164 euro, while a set of three nodes would cost approximately 166 euro. Before buying, be sure to specify how many devices will be included in the purchased kit.
Answers to emerging questions about the functioning of the Tenda mesh systems can be found on the official website of the manufacturer. Information about all new updates will also be available here.