Modular Mesh^TM Configurations. MeshDynamics MD4000 nodes support up to 4 radios in a single enclosure.

Slots 0, 1 is used for the 5.8GHz or 4.9GHz backhaul uplink and downlink radios. The backhaul radios operate on non-interfering channels in the same  frequency band. This forms the Structured Mesh Backhaul. Slot 2 is generally used for a 2.4G or 4.9G AP radio. Slot 3 may be used for a 2nd downlink, 2nd AP radio or scanning radio intended to rapid hand off in high speed mobility applications. 
 
Note: All models are software configurable. Models may be field upgraded by updating software and inserting additional radio cards.
 


Click on an image above to access application notes on that configuration.

4350 is a popular configuration request with one 2.4GHz AP radio in slot 2 and a 5.8 GHz uplink and downlink in slots 0,1.
4250 is 4350 without the AP radio - for remote video surveillance and perimeter security, where client access is not required. 
 
Other configurations involve multiple service radios (AP) with sectored antennas for range or more sectored backhauls downlinks for forked paths. Popular supported models are listed below. The Model Number Scheme lists currently supported configurations:

More backhaul downlinks for higher capacity  4452 and 4454 support two and four backhaul downlinks respectively. Consider these models if the distribution of bandwidth needs to be shared along multiple directions. [Example]. If more bandwidth distribution is needed these models can distribute 40-44 Mbps TCP/IP (4452) or 80-88 Mbps TCP/IP (4454) as root nodes. 
 
More service radios (Access Points): 4458 and 4424 support multiple service radios where high client density is anticipated. The 4458 with two service radios (4458-AAII) has proven to be particularly useful in underground mining applications. [More]
 
Scanning radio for high speed mobility: 4455 and 4325 use a scanning radio in slot 3 to ensure rapid switch over from node to node in a mobile setting. Field tests demonstrated real time video transmission from vehicles traveling at 50+ mph [More]
 
Custom Configurations (For OEMs): All the radios may be custom configured to be uplink, downlink, service, scanner or a silent logging radio.  Please review the Model Number Scheme for a listing of currently supported configurations.
 
Choice of Backhaul: 5.8GHz vs 2.4GHz.  4220 and 4325 are the rough 2.4GHz equivalent of the 4250 and 4455 5.8GHz backhaul products. When deciding whether to use 2.4GHz based products (4220,4325) RF pollution must be considered. The clients are 2.4GHz and will interfere with a 2.4GHz node-to-node (backhaul) link. In addition, 802.11b clients - if attached to the 2.4GHz backhaul (e.g. 4220, 4325) slows the performance of of the node-to-node link. 4220 and 4325 mesh nodes thus should be limited in servicing few child nodes. On the positive side, 2.4 GHZ has about twice the range at 5GHz, so 4325, 4220 are preferable where range supersedes backhaul capacity. 4325, 4220 are also used when the nodes are edge based - that is no child nodes connected to them. [Image]. In all other situations, 5GHz mesh nodes (4455, 4458, 4452, 4454, 4350) are suggested. 

Antenna Selection Options. If omni antennas are used then the MeshDynamics Mesh topology may be viewed as a MP-to-MP tree (figure below, right). Changing from omni to sectored antennas, restricts the "field of view" of the mesh nodes. The topology then resembles a P-to-P link (left). If there are multiple downlinks(4452, 4454) then P-to-MP configurations are also supported (center). Note than in all cases, auto discovery, self healing and dynamic channel management are supported, within restrictions of the field of view of the antenna (e.g. what the radios "hear"). Antenna options are discussed in the installation guide and FAQ.  

GPS Position Location Support A GPS radio is optional for all models. The GPS location information is transmitted periodically with the mesh node heart beat. The mesh node location is automatically updated on the NMS. The NMS uses maps imported from www.openstreetmap.org and dynamically manages the background image movement to ensure that the current location is correctly depicted)  The GPS radio does not use a radio slot but may use an antenna port, depending on whether all  antenna ports are in use or not. See GPS Options and NMS Tracking Video

Hazardous or Explosion Proof environments. The components on MD4000 single board computer runs on 3.3V. If 3.3V are supplied directly to the MD4000 board (eliminating the DC-DC converter) then the system becomes intrinsically safe. No sparks can occur at that low voltage. The higher amperage demanded at this lower voltage is between 5-6 Amps. The mesh node enclosure requires power connectors other than the standard RJ45 connectors. See 3.3 VDC enclosure modifications.  
 
Web Page MD4000 Network Manager. Overview of our Network monitor and configuration system.
Web Page Frequently Asked Questions. On Antenna selection, GPS, Mobility extensions, Hazard proof enclosures.
 
Download MD4000 Product Brochure. Includes technical specifications and standard product configurations.
Download MD4000 Installation Guide. Antenna mounting and placement, model configuration, trouble shooting.
Download MD4000 Network Configuration Guide. Detailed instructions on setting SSID, Encryption, QoS, VLANs etc.