Gabriel Reyes, CWNA, CWDP

Field Application Engineering, EnGenius Technologies, Inc.

 

In this setup guide, a wireless network topology using the Mesh feature of
the EnGenius® Neutron system. The example presented here will have
three EWS1205CAMs linked together via mesh, as shown in the figure below.
Note, in order for mesh to be available, the EWS switch controller
firmware must be version c1.8.57 or later, or version 0.12.8 or later on
ezMasterTM.

In this tolpogy of the mesh domain, the two Remote Nodes are each one hop
away from the Root Node. The bandwidth requirment per EWS1025CAM camera
(using H.264, 1080P, 30 fps) is approximately 5-6 Mbps. EnGenius®
does not recommend having a Remote Node farther than three hops from the
Root

Node. In the above example, we have the Root Node labeled as,
 “root” , and the two Remote Nodes labeled as
“nonroot1” and “nonroot2”.

Prior to adding APs and defining AP Groups, designate the band to enable
mesh on, and establish the key parameters such as the numerical mesh
domain (Mesh ID) and password to join the mesh domain.  Set an
appropriate threshold, so that a mesh link to a Remote Node will not be
established if the RSSI reading is below the threshold. These settings are
found under Controllerà MeshàMesh Profile.   This
setting is global to the EWS controller, and will be common amongst all AP
Groups that have mesh enabled.




Best Practice:  The network design should cluster the
APs into groups consisting of up to four Remote Nodes that are only
one hop away from a Root Node. 

Thus, at least 20% of your APs, distributed roughly evenly throughout the
property, should be Root Nodes.  Each Remote Node is therefore
nominally only one hop away from a Root Node.  In the event of a
failure of a Root Node, the nearby Remote Nodes will then only be 2-3 hops
away from another Root Node.  This approach generally requires
creating additional Root Nodes, which can be done either by running
Ethernet or fiber-optic cable to the remote locations, or by establishing
dedicated point-to-(multi)point WDS Bridge links to create
“wireless wires” from the root AP back to the wired network.

In mesh environments with multiple Root Nodes, mesh clusters can be
established by creating a unique AP Group per mesh cluster.  Thus,
each AP Group shall contain one Root Node and the desired Remote Nodes
that should nominally be connecting to it.  The settings of each AP
Group are identical, except for the channel.  Each AP Group needs to
be on an independent channel to ensure that neighboring mesh clusters do
not self-interfere.

Creating an AP Group / Mesh ClusterConnect the Root Node to the EWS
switch, and then add the Root Node in the same manner as any wired EWS
access point. In order for the mesh feature to be enabled, the Root Node
must be in a dedicated AP Group with the mesh feature enabled. All APs
that are part of the same mesh cluster need to be placed in the same AP
Group. 

Add the Root Node to the EWS switch (e.g EWS1025CAM), to be managed by the
controller, just as is done with any wired EWS AP.

Add the detected Rood Node, and then assign the unit a static IP address
or let the unit get an IP address via DHCP.

After adding the AP to the EWS switch, EnGenius® recommends that the
device be named by its location with a “root” or similar at
the end, to aid in the identification of the AP once all mesh APs are
managed by the EWS switch. This is done by clicking the current device
name under the column device name.

The AP name change should now be reflected under the “Device
Name” column.

Once the Root Node is online, create an AP Group to add all the devices
that are going to be in the mesh cluster. This will enable all of the mesh
APs to be easily managed from the controller.

The AP Group setting is found under Controller→Device
Management→AP Groups. Click the “Add” button to
create a new group for all the mesh APs that shall be in the mesh cluster.

Name the newly created group and add the Root Node to the group.

Once added to the AP Group, verify the appropriate Radio Settings. Make
sure the Country is appropriate for the regulatory domain the wireless
system is deployed in.

In order for mesh to be enabled without any errors, especially on the 5GHz
band, the following items much match:

  • Channel HT Mode
  • Channel Number
  • Transmit Power

 

We recommend that mesh deployment be in the 5 GHz band when possible,
using either 40 MHz or 80 MHz channels.[1]
For the 2.4 GHz band, it is best practice to use 20 MHz channel HT mode of
20 MHz, lowest transmit power, and a static non-overlapping channel of
either 1, 6, or 11 for the 2.4 GHz radio. This should be set individually
on each AP to ensure alternating channels.

 




Best Practice:  Each Root Node should be set on a static
independent channel, and each Remote Node should be set to
“auto channel”
.


[2]

 
This is done to maximize the airtime capacity of the overall network, so
that multiple neighboring Root Nodes do not create
self-interference.  The Remote Nodes are set to auto-channel so that
they can fail over to a different Root Nodes in the event of the failure
of their primary

 


[1]
In the c1.8.57 firmware release, only 20 MHz or 40 MHz channels in the
UNII-1 (36-48) and UNII-3 (149-161) portions of the 5 GHz band are
supported.  This will be addressed in a future firmware
release.


[2]
In the c1.8.57 firmware release, auto-channel is not supported for APs
in mesh mode.  Accordingly, each AP Group needs to have all APs in
that mesh cluster set to a static and non-overlapping
channel.   This will be addressed in a future firmware
release.

 

Root Node.  When utilizing point-to-(multi)point WDS Bridge links to
establish Root Nodes, these must also be on static independent channels,
and thus must be accounted for in the overall channelization plan. 

After setting up the Radio settings in the AP Group and setting up the 2.4
GHz radio with one (or more) SSIDs for client access, the next step is to
enable the mesh setting to desginate the AP Group as utilizing mesh.
 This is found under the Advanced Setings tab. Enabling the
 Mesh option in the group setting will desginate the current device
in the group as the Root Node.




Best Practice:  Mesh APs should generally be configured
to operate in Mesh Point mode.



[1]
 The loss of bandwidth capacity from lacking wireless 5 GHz wireless
connectivity is minor compared to the loss of bandwidth capacity from
losing 50% of bandwidth per hop.  This also allows for the transmit
power of the mesh radios to be set at their


maximum


value, so as to provide the maximum signal strength between nodes without
being imbalanced with the low transmit power capability of most 5 GHz
client devices.

Hit “Apply” to save the AP Group settings.

The lights of the Root Node should be as shown below. Only Root Nodes
(i.e. nodes with a “wired connection” to the network) will
have the LAN light illuminated.


[1]
In the c1.8.57 firmware release, this option is not available in the AP
Group setting, and must be set by logging into the access point
directly.  This will be addressed in a future firmware
release.

Repeat this process for all other Root Nodes on your network, placing them
in separate AP Groups.    For the Root Node(s), click on
the AP under the “Access Point” screen and override the
settings to set a static and non-overlapping channel for each Root Node.

 

When configuring a new mesh network, the Remote Nodes should initially be
wired into the controller like any wired EWS AP, added to the controller,
and added to the correct AP Group.  The channel for the mesh radio
(typically 5 GHz) should be left on “Auto”, though do
remember to set the appropriate static channel on the Wi-Fi client access
band (typically 2.4 GHz).[1]    Once the Remote Node APs are fully provisioned and
part of the AP Group, they can be disconnected from the controller and
installed in the remote location.  Once the Remote Node APs are
powered up at the remote locations, they will automatically attempt to
connect via mesh.

Adding a Remote Node to an Existing Mesh Network

If Remote Node APs are already installed before they are configured, or if
a Remote Node AP needs to be added to the network but access to the wired
network core is not practical, then the following steps can be followed to
add a Remote Node to the network. 

Login to the Remote Node directly. The AP by default will be in standalone
mode, and can be accessed via the username “admin” and the
password “admin. Once logged in, the AP will ask for the login
password to be changed as well as to create a guest account. Since this AP
will ultimately be added to the same AP Group, group it is recommended to
skip this step by pressing the skip button.


[1]
In the c1.8.57 firmware release, auto-channel is not supported for APs
in mesh mode.  Accordingly, each AP Group needs to have all APs in
that mesh cluster set to a static and non-overlapping
channel.   This will be addressed in a future firmware
release.

After pressing the skip button the device will redirect to the live video
feed page (for the EWS cameras) or to the device status screen (for EWS
APs). Click on the settings icon to be redirected to the settings page.

The only settings that are needed for the Remote Node AP to connect to the
Root Node AP is the appropriate band that mesh is enabled on, the proper
wireless channel, and specifying the correct Mesh ID and password.

Under Access Point→Mesh→Settings is where the mesh settings
are configured for the device. The Remote Node will be configured as a
Mesh Point. It is imperative that the Mesh ID and Password match the Root
Node, in order for the Remote Node to be properly associated and
authenticated within the Root Node’s mesh domain.



Best Practice:  Mesh APs should generally be configured to
operate in Mesh Point mode.
 The loss of bandwidth capacity from lacking wireless 5 GHz wireless
connectivity is minor compared to the loss of bandwidth capacity from
losing 50% of bandwidth per hop.  This also allows for the transmit
power of the mesh radios to be set at their


maximum


value, so as to provide the maximum signal strength between nodes without
being imbalanced with the low transmit power capability of most 5 GHz
client devices.

After applying the settings, the device reminds the installer to ensure
that the unit is configured to be operating on the same wireless channel
as the Root Node, in order to establish a mesh connection.

The wireless settings of the device can be configured under Access
PointàNetworkàWireless. Ensure the Remote Node is configured to
operate on “auto” so that it will automatically detect and
associate to the closet mesh node.[1]

The name of the device may also be set under the wireless settings page.
It is recommended that the name be configured under the wireless settings
page, while the device is still in standalone mode so it would be easier
to identify once the device is added to the EWS switch to place the device
in managed mode. The name of the AP should correspond to its location on
the network.

The figure below shows the lights on the Remote Node AP. Note that since
this unit does not have a wired connection to the network the LAN light is
not illuminated like the Root Node would have.


[1]
In the c1.8.57 firmware release, auto-channel is not supported for APs
in mesh mode.  Accordingly, set the channel to correspond to the
static channel of the desired Root Node.

Once the Remote Node has established a mesh connection with a Root Node,
the EWS switch will detect the Remote Node and display that it has been
detected. Notice the name of the AP shall match the name of the Remote
Node configured earlier.  Add the Remote Node and configure it to be
managed by the EWS switch. 

After the newly added unit displays Online status, add the Remote Node to
the same AP Group as the Root Node under Controller→Device
Management→AP Groups.

 

Add the Remote Node to the same AP Group as the Root Node.

Once the newly added Remote Node is displaying Online status, change the
local non-mesh radio settings.

By clicking on the device name. Under the Wireless Radio Settings, check
the box Override group to decouple that particular setting from the AP
Group settings. In order to avoid co-channel interference on the 2.4 GHz
radio side, set the APs to all have unique static non-overlapping 2.4 GHz
channels of either 1, 6, or 11.

The status of the mesh links can be checked under
ControlleràMeshàNode List. As seen below, the Remote Node with
the name of EWS1025CAM-nonroot2 is two hops away. As a reminder,
EnGenius® does not recommend any Remote Node to be greater than three
hops from the main Root Node.

 

In order to see the Mesh topology in a more visual way, use the Mesh view
under Controllerà VisualizationàMesh View.

The above view shows when both the Remote Nodes can communicate directly
with the Root Node.

Here is the topology with two hops, where the second Remote Node does not
have a direct mesh connection to the Root Node, and thus must connect to
another Remote Node.

Below is when only one Remote Node is able to connect to the Root Node.

Here is the same topology view, if logged into the 1025CAM UI under Mesh
Link→Link Status.

It is recommended that the maximum hop count be no more than three hops
due to the amount of throughput degradation and latency increase that each
hop introduces. As seen in the throughput test found under
Controller→Mesh→Mesh Tools→Throughput.

The same test can be done while when logged into the UI of the 1025CAM
under Mesh Link→Throughput.

 


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