Overview of Mesh Access Points

Mesh APs learn about their environment when they boot up. Mesh APs are either configured as one of the following:

• Mesh Portals—An AP that uses its wired interface to reach the managed device. For more information, see Mesh Portals .

• Mesh Points—An AP that establishes an all-wireless path to the mesh portal. For more information, see Mesh Points.

Mesh portals and mesh points are also known as mesh nodes, a generic term used to describe APs configured for mesh.

A mesh radio’s bandwidth can be shared between mesh-backhaul traffic and client traffic. You can, however, configure a radio for mesh services only. If you have a dual-radio AP, a mesh node can be configured to deliver client services on one radio, and both mesh and WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. services to clients on the other radio. If you configure a single-radio AP to deliver mesh services only (by disabling the mesh radio in its 802.11a 802.11a provides specifications for wireless systems. Networks using 802.11a operate at radio frequencies in the 5 GHz band. The specification uses a modulation scheme known as orthogonal frequency-division multiplexing (OFDM) that is especially well suited to use in office settings. The maximum data transfer rate is 54 Mbps. or 802.11g 802.11g offers transmission over relatively short distances at up to 54 Mbps, compared with the 11 Mbps theoretical maximum of 802.11b standard. 802.11g employs Orthogonal Frequency Division Multiplexing (OFDM), the modulation scheme used in 802.11a, to obtain higher data speed. Computers or terminals set up for 802.11g can fall back to speed of 11 Mbps, so that 802.11b and 802.11g devices can be compatible within a single network. radio profile), that mesh node cannot deliver WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. services to its clients.

APs operate as thin APs by default; their primary function is to receive and transmit electromagnetic signals; other WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. processing is left to the managed device. When planning a mesh network, you manually configure APs to operate in mesh portal or mesh point roles. Unlike a traditional WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. environment, local mesh nodes provide encryption and traffic forwarding for mesh links in a mesh environment. Virtual APs are still applied to non-mesh radios.

For mesh and traditional thin AP deployments, the Aruba Mobility Conductor provides centralized provisioning, configuration, policy definition, ongoing network management, and wireless and security services. However, unlike the traditional thin AP case, mesh nodes also perform network traffic encryption and decryption, and packet forwarding over wired and WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. links.

You can configure the AP for mesh on the Mobility Conductor using either the WebUI or the CLI Command-Line Interface. A console interface with a command line shell that allows users to execute text input as commands and convert these commands to appropriate functions.. All mesh-related configuration parameters are grouped into mesh profiles that you can apply as needed to an AP group or to individual APs. You must first define and configure the mesh profile, and then configure the APs to operate in mesh mode. For more information, see the following topics:

• Creating and Editing Mesh Radio Profiles

• Configuring Ethernet Ports for Mesh

• Provisioning Mesh Nodes

Mesh Portals

The mesh portal is the gateway Gateway is a network node that allows traffic to flow in and out of the network. between the wireless mesh network and the enterprise wired LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server.. You configure an Aruba AP to perform the mesh portal role, which uses its wired interface to establish a link to the wired LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server.. You can deploy multiple mesh portals to support redundant mesh paths (mesh links between neighboring mesh points that establish the best path to the mesh portal) from the wireless mesh network to the wired LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server..

The mesh portal broadcasts the configured MSSID Mesh Service Set Identifier. MSSID is the SSID used by the client to access a wireless mesh network. or mesh cluster name, and advertises the mesh network service to available mesh points. Neighboring mesh points that have been provisioned with the same MSSID Mesh Service Set Identifier. MSSID is the SSID used by the client to access a wireless mesh network. authenticate to the portal and establish a secure mesh link over which traffic is forwarded. The authentication process requires secure key negotiation, common to all APs, and the mesh link is established and secured using AES Advanced Encryption Standard. AES is an encryption standard used for encrypting and protecting electronic data. The AES encrypts and decrypts data in blocks of 128 bits (16 bytes), and can use keys of 128 bits, 192 bits, and 256 bits. encryption. Mesh portals also propagate channel information, including CSAs.

Mesh Points

The mesh point is an Aruba AP configured for mesh and assigned the mesh point role. Depending on the AP model, configuration parameters, and how it was provisioned, the mesh point can perform multiple tasks. The mesh point provides traditional Aruba WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. services (such as client connectivity, IDS Intrusion Detection System. IDS monitors a network or systems for malicious activity or policy violations and reports its findings to the management system deployed in the network. capabilities, user role association, LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server.-to-LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server. bridging, and QoS Quality of Service. It refers to the capability of a network to provide better service and performance to a specific network traffic over various technologies. for LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server.-to-mesh communication) to clients and performs mesh backhaul or network connectivity. A mesh radio can be configured to carry mesh-backhaul traffic only. Additionally, a mesh point can provide LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server.-to-LAN Local Area Network. A LAN is a network of connected devices within a distinct geographic area such as an office or a commercial establishment and share a common communications line or wireless link to a server. Ethernet Ethernet is a network protocol for data transmission over LAN. bridging by sending tagged or untagged VLAN Virtual Local Area Network. In computer networking, a single Layer 2 network may be partitioned to create multiple distinct broadcast domains, which are mutually isolated so that packets can only pass between them through one or more routers; such a domain is referred to as a Virtual Local Area Network, Virtual LAN, or VLAN. traffic across a mesh backhaul or network to a mesh portal.

Mesh points use one of their wireless interfaces to carry traffic and reach the managed device. Mesh points are also aware of potential neighbors, and can form new mesh links if the current mesh link is no longer preferred or available.

Mesh Clusters

A mesh cluster is a logical set of mesh nodes that share the common connection and security parameters required to create mesh links. Mesh clusters are similar to an ESS Extended Service Set. An ESS is a set of one or more interconnected BSSs that form a single sub network. in a WLAN Wireless Local Area Network. WLAN is a 802.11 standards-based LAN that the users access through a wireless connection. infrastructure. Mesh clusters are grouped and defined by a mesh cluster profile, as described in Mesh Cluster Profiles

Mesh clusters may enforce predictability in mesh networking by limiting the amount of concurrent mesh points, hop counts, and bandwidth used in the mesh network. A mesh cluster can have multiple mesh portals and mesh points that facilitate wireless communication between wired LANs.

The following shows two mesh clusters and their relationship with the managed device.

Figure 1  Sample Mesh Clusters

Fast Roaming in Mesh Networks

ArubaOS supports fast roaming for APs deployed in a wireless mesh network. The mesh points for which fast roaming is enabled are called mobility mesh points. The mobility mesh points can dynamically reselect and reconnect to a new selected mesh point based on detection of RF Radio Frequency. RF refers to the electromagnetic wave frequencies within a range of 3 kHz to 300 GHz, including the frequencies used for communications or Radar signals. conditions such as beacon frames and RSSI Received Signal Strength Indicator. RSSI is a mechanism by which RF energy is measured by the circuitry on a wireless NIC (0-255). The RSSI is not standard across vendors. Each vendor determines its own RSSI scale/values. value.

The fast roaming feature in mesh network involves the following steps:

1. Detecting roaming condition—The mesh points identify fast moving environments such as buses or the subway to apply fast roaming.
2. Background scanning—The mesh points perform fast scanning of other mesh points in the background. In fast scanning, the radio immediately initiates another channel scan request when the current scan request is complete. The background scan implies that when mesh is connected, the mesh point collects information about surrounding radio channels. The background scan is triggered due to missed beacon frames or low RSSI Received Signal Strength Indicator. RSSI is a mechanism by which RF energy is measured by the circuitry on a wireless NIC (0-255). The RSSI is not standard across vendors. Each vendor determines its own RSSI scale/values. value below the threshold.
3. Roaming or reconnection—The mesh points rapidly choose the best mesh point neighbor to connect from all the neighbors.

Important Points

• This feature is currently supported on 300 Series, 303 Series, 303H Series, 310 Series, 318 Series, 360 Series, 370 Series, 370EX Series, 500 Series, 500H Series, 510 Series, 530 Series, 550 Series, 570 Series, and 580 Series access points.
• A mobility mesh point only connects to MPP (A mesh portal with hop count = 0).
• A mobility mesh point's hop count is always 1.
• A mobility mesh point has no children.

Configuring Fast Roaming for Mesh APs

The following procedure configures fast roaming for mesh APs:

1. In the Mobility Conductor node hierarchy, navigate to the Configuration > System > Profiles tab.
2. Under the All Profiles pane, expand Mesh and select Mesh Radio.
3. Perform one of the following steps to create a new mesh radio profile or edit an existing profile:
   • To create a new mesh profile, click + in the Mesh Radio Profile: <New Profile> page and enter the profile Name.
   • To edit an existing mesh profile, select the profile that you want to edit from Mesh > Mesh Radio.
4. Under Advanced, select the Mesh Mobility check box.
5. Enter a value in the Mobility RSSI Threshold field.

   The range is 10-50 and the default value is 15.

6. Enter a value in the Mobility Beacon Miss Number field.

   The range is 10-25 and the default value is 16.

7. Click Submit.
8. Click Pending Changes.
9. In the Pending Changes window, select the check box and click Deploy Changes.

The following CLI Command-Line Interface. A console interface with a command line shell that allows users to execute text input as commands and convert these commands to appropriate functions. commands configure fast roaming for mesh APs.

Mesh Network with Mixed Indoor and Outdoor APs

Indoor and outdoor APs participating in a mesh must be deployed with RF Radio Frequency. RF refers to the electromagnetic wave frequencies within a range of 3 kHz to 300 GHz, including the frequencies used for communications or Radar signals. or regulatory settings, or assigned RF Radio Frequency. RF refers to the electromagnetic wave frequencies within a range of 3 kHz to 300 GHz, including the frequencies used for communications or Radar signals. profiles, which allow overlapping channels to operate between the APs in the following scenarios:

• When setting up a mesh network between indoor and outdoor APs.

• When provisioning indoor APs as outdoor APs.

• When using AirMatch or ARM Adaptive Radio Management. ARM dynamically monitors and adjusts the network to ensure that all users are allowed ready access. It enables full utilization of the available spectrum to support maximum number of users by intelligently choosing the best RF channel and transmit power for APs in their current RF environment. to support dynamic channel selection.

This allows both indoor and outdoor APs to always operate on the same channels. If you do not deploy the indoor and outdoor APs with regulatory settings or assigned RF Radio Frequency. RF refers to the electromagnetic wave frequencies within a range of 3 kHz to 300 GHz, including the frequencies used for communications or Radar signals. profiles with overlapping channels, the indoor and outdoor channels for a given regulatory domain may not overlap. When the indoor and outdoor APs share a regulatory profile and are provisioned for the correct network environment, the dedicated indoor or outdoor mesh portals are deployed to support indoor or outdoor mesh points respectively.

The provisioned Indoor or Outdoor role of an AP is defined by the location of its antennas. Hence, when an indoor AP uses antennas installed in an outdoor area, the AP must be provisioned as Outdoor. For example, if the external outdoor antennas of an indoor AP are deployed to support outdoor APs as mesh points, and the indoor mesh portal is running on UNII-1 channel 36, then the outdoor mesh points may not be able to view the mesh portal to associate with. This occurs when the regulatory domain of that country has different allowed channels for indoor and outdoor APs, and the regulatory domain may disallow UNII-1 channels and UNII-3 channels for outdoor and indoor uses respectively. As a result, the mesh points cannot access UNII-1 APs. However, once the indoor AP with outdoor antennas is provisioned as an outdoor AP, that AP can then run on a UNII-3 channel, allowing the mesh points to access the portal.