Frequently Asked Questions

1. How is a wireless mesh network different from a standard wireless network?
   • A standard Wi-Fi network operates on unlicensed radio spectrum with each router or node hardwire connected to the internet. A mesh network operates on the same radio spectrum but only one node in a particular network needs to be hardwired to the internet. This allows network signals to freely route via the most efficient path back to the hardwired node enhancing the speed and reliability of communications.
2. Is mesh network equipment compatible with non-mesh routers and devices?
   • Yes, mesh network equipment can interface with most standard, existing Wi-Fi devices, but those devices cannot serve as a router in the mesh network. For example, a computer with an 802.11 compatible wireless card will work equally well on a mesh or non-mesh network.
3. What is a peer to peer network?
   • Peer to peer networks allow two individual nodes in a network to communicate directly with each other vs. routing all signal through a parent or hub node.
4. What are point to point or point to multipoint networks?
   • Point to point networks have one node hardwired to the internet or corporate server with a destination node (wired or wireless) connecting to that base node. Point to multipoint networks have a base node hardwired to the internet or corporate server that allow multiple client nodes to have a simultaneous connection to the base node (wired or wireless).
5. What is multi-hopping?
   • Signal multi-hopping is the ability for any mesh network node to skip its signal across multiple wireless mesh routers back to the base node that is hardwired to the internet or corporate server.
6. What is a tree topology?
   • Most mesh networks use a network design that forces signals to travel to a control or parent node before getting routed to another node in the network. This hub and spoke model creates enormous inefficiencies in signal routing, especially when high throughput applications such as video streaming are deployed.
7. What is cross IP subnet roaming and why does it matter?
   • Azalea has a proprietary technology that lets any node in its mesh networks handoff a signal directly to any other node without going through a parent or hub node first. This unique design creates more efficient network traffic flow especially in high throughput applications such as video streaming.
8. In detail, what are the key attributes of a Wireless Mesh Network?
   • Wireless Mesh Network (WMN) is a next generation wireless technology that provides solutions for public access wireless Local Area Network (LAN) and Metropolitan Area Network (MAN).
     
     Compared with the traditional wireless LAN (WLAN), WMN transmits wireless data into the wired network, dramatically reducing the need for costly wired connections and simplifying network deployment.
     
     WMN features a discretionary topology like a fishing net. Because of its employment of radio frequency transmission instead of wired transmission, there can be multiple paths from any point to another (hence the name wireless mesh network).
     
     The latest WMN technology has evolved through two generations:
     
     First Generation WMN
     The first generation WMN is the so-called Layer 2 WMN (alternatively known as the switching-based WMN). Nowadays, most vendors provide products that employ switching-based WMNs (namely, data transmitted between APs on Layer 2). Switching-based WMN products are the fusion of a wireless switchboard and an AP.
     
     A Layer 2 WMN, as such, is not furnished with a routing function; it must possess a root node for data switching. When the data at Node A are transmitted to Node B, traffic goes first to the root node to transmit data, instead of opting for the nearest path between Node A and Node B.
     
     For the reasons above, Layer 2 WMNs have a number of flaws, such as:
     • Inability to quickly converge
     • All communications traffic converges onto the same gateway, thus causing traffic jams at the gateway and in its vicinity
     • If only one node becomes problematic, the entire data transmission process is affected
     • The unavailability of an alternative pathway causes lengthy delays
     • Inefficient use of effective bandwidth
     These technical flaws in WMN technology have caused many users to lose confidence in WMNs, as they think it impossible to deploy a WMN over a vast area. In practice, it has been proven that upon reaching the 4th hop, the data transmission rate of Layer-2 WMNs would have been reduced to about 0bps.
     
     Second Generation WMN
     The second generation WMN is the so-called Layer-3 WMN (alternatively known as the routing-based WMN). The latest WMN products developed by Azalea incorporates this technique, overcoming the deficiencies inherent in Layer-2 WMNs.
     
     A WMN furnished with a routing function is the true manifestation of mesh routing. When data is transmitted from Node A to Node B, it becomes unnecessary to conduct data transmission at the root node; instead, data reaches Node B via the shortest path from A to B.
     
     A WMN delivered with routing functionality determines the structure of a wired network. Routers in each wireless network not only allow users in its covered area to gain access to the Internet; it also serves as basic infrastructure in this network to transmit data to the appropriate destination via WMN routing. Routing-supported mesh networks are highly flexible and error-tolerant. It simplifies the LOS (line-of-site) issue and expands network coverage with minimal network infrastructure and the lowest possible network interconnection cost.
     
     As a result of these inherent features, WMN has the potential to surpass existing modes for accessing broadband networks that are dependent upon cables and DSL. In addition, WMN is able to provide a roaming function for mobile communications and a network routing function that requires minimal network infrastructure, all of which are hard to accomplish using wired networks.
9. How did WMN originate?
   • The development of 802.11-WLAN-based WMN originated from techniques used in the military. Specifically, mobile networks in a battlefield need to deliver higher data transmission rates to avoid being detected and to prevent intentional interference. In addition, this technology is largely IP based technology, which supports a multi-point-to-multi-point mesh topology. This topology consists primarily of four parts: mobile controller, intelligent access point, wireless routers and PCMCIA WLAN network interface cards, with the mobile controller as the centerpiece. The key technology in this deployment is Mobile Ad Hoc Networks Routing which makes wireless broadband feasible.
10. How many layers does the WMN protocol encompass? What are they called? On which layer has Azalea Networks made a breakthrough?
    • The bottom layer is the physical layer, which primarily addresses physical characteristics such as strength of signal, signal transmission, etc. Above that is the data link layer, which defines the access strategy for sharing the physical medium, including data link and media access. The third layer is the Network Layer, providing a means for communicating open systems to establish, maintain and terminate network connections. The IP protocol lives at this layer, and so do some routing protocols. Further above is the transmission layer (i.e. TCP or UDP), which mainly deals with data packets loss during transmission. The topmost layer is the application layer, This is where you find your end-user and end-application protocols, such as telnet, ftp, and mail (pop3 and smtp).
      
      Azalea's breakthrough is on the second and third layer, namely the data link layer and network layer. Azalea's Radio Frequency management module, routing module, and intelligent roaming modules work on these layers in a cross-layer fashion so Azalea's products can achieve maximum throughput, minimum interference and the best QoS for upper layer applications.
11. What are the advantages of WMNs?
    • Compared to traditional Wi-Fi technology, WMN excels in that it is no longer dependent on wires, allowing MANs for vast areas to be built wirelessly. Another advantage of WMN is that it supports fast-speed roaming and shifting among routers; therefore, WMN delivers a much better performance than Wi-Fi.
      
      Compared to Wimax, WMN is a more sophisticated option. In fact, Wimax remains quite undeveloped to this point because there is no existing Wimax standard, not to mention Wimax chips to support mobile communication. According to conservative estimates, Wimax terminals will not be available for another five years. In addition, because Wimax employs MAC layer technology which is far more complicated than Wi-Fi, the cost of Wimax equipment (including base stations and terminals) is expected to be much greater than Wi-Fi. Another drawback of Wimax, compared to WMN, is that the frequency range employed by Wimax is levied charges in many countries; as a result, the high licensing fees are bound to dramatically push up Wimax's overall costs.
      
      Compared to 3G, Azalea's products are much more cost-efficient while providing bandwidth 2x greater than 3G products. At present, the data transmission rate of 3G is 500Kbps at the highest; while Azalea's wireless routers can boost data transmission rate to 108Mbps. Therefore, Azalea's wireless routers can support transmission of superior quality videos, which is hard to achieve with 3G products.
      
      Networks constructed by Azalea's wireless routers are self-healing. It supports multi-point access therefore a single point failure or partial network failure will not affect the entire network. On top of that, Azalea's APs and terminals are priced lower than 3G products, and the terminals are compatible with current computer types and PDA network cards. Azalea's WMN also has high security and multiple modes of encryption and authentication. It supports Virtual Private Network(VPN) to fulfill the requirements from corporate customers, as well as Ad-Hoc and temporarily formed networks. All of these features are beyond 3G‘s capabilities.
      
      Compared to wired technology, WMN allows its users to connect Wi-Fi cell phones to talk while moving and to surf the Internet with a laptop or PDA anywhere in its wireless network. These capabilities are not provided by wired technology. Secondly, installation, debugging, and maintenance are all much more easily accomplished with a WMN, saving costs associated with deploying wired networks, such as mounting, cabling, installation and configuration of switches and routers. From a cost perspective WMN has a lower total cost of ownership than wired technology.
12. How would you describe the relationship between WMN and Wi-Fi?
    • Technologically speaking, WMN is fully compatible with the Wi-Fi standard on the physical layer and the link layer; in addition, it strengthens the Wi-Fi standard. The traditional Wi-Fi technology requires each AP to be equipped with one wire to provide wireless coverage for a target area; in contrast, WMN employs a radio frequency to substitute its wired counterparts. Without the limitation of wires, WMN allows users to deploy dynamic networks in an area as vast as they may desire. 
13. Can Azalea's products be used to construct, a LAN, WAN or MAN (mesh)?
    • Yes, our products can be used to construct a LAN, WAN or a MAN, and WMN has its unique advantages over Wi-Fi, when used to construct a MAN.
14. Can a wireless network really be secure? Absolutely. Azalea networks have a wide array of security features, including:
    • Supports several sophisticated data encryption algorithms, including TKIP (up to 128bit), PSK, AES, TLS and TTLS
    • Fully supports 802.11i, MAC address filtering, Radius, WEP, WPA, WPA2 and 802.1x
    • Multi-VLAN enables isolation of users and physical layer isolation of wireless terminals
    • Access authentication for wireless nodes to prevent access by unapproved routers
15. What if I want to move my network?
    • If you have a wired network, this is not a question you ever want to hear. It's costly and takes a lot of time and expense to move wires. With an Azalea network, you simply move the router(s) to another location. Turn on the router(s) and the network self-detects each new node, authenticates them and you've moved your network.
16. What is the benefit of peer-to-peer communication?
    • Peer to peer communication simply lets one node talk directly to another without having to pass through a controlling node. This shortens transmission times and is critical for high throughput applications.
17. How can I expand my network as my needs evolve?
    • With an Azalea network, you simply deploy another router inside or outside. If it's outside, it can be on a pole with no power run to it – simply add a modest solar panel. Turn on the router and the network self-detects the new node, authenticates it and you've added to your network.
18. How many routers do I need to be connected to the internet?
    • Only one router in a given network is required to be connected to the internet. Additional connections can add speed by minimizing hops. This is worked out in final site planning.
19. What does self-forming mean?
    • Mesh networks constantly scan their domain for new, properly authenticated devices. Once discovered the network dynamically changes with the equipment it's interacting with. Its self-discovery feature makes it constantly checking to detect new devices. The intelligent routing in each WMN router also means the network is constantly load balancing to even out traffic flow and detects any sources of interference or impedance and routes to other nodes around the problem so it is constantly self-healing.
20. Aren't mesh systems more expensive than traditional wired networks?
    • Mesh networks on initial installation may be more or less expensive, depending on where wire needs to be run. Wireless networks, even with more costly routers, can cost a fraction of expensive wiring in industrial settings. Total cost of ownership will be lower for mesh networks over time because moving equipment doesn't require moving wires unless it happens to be the base node that connects to the internet.
21. Do I have to implement the entire system at once?
    • You can add and move nodes as business needs dictate. Start small and add as applications and needs are identified.