Home-as-a-Hotspot - Public WiFi

In the context of OpenSync, Home-as-a-Hotspot – Public WiFi represents the ability of a gateway node to broadcast a secondary public SSID.

Using Public WiFi, each location (single-family house, multi-tenant building, small shop, etc.) can provide a separate public WiFi network to guests or visitors. In addition, Public WiFi also serves as a method to provide service roaming between various mobile network operators. In this context, mobile operators might use Passpoint to offer the roaming users their home network mobile services using public WiFi networks regardless of current location. 

Within OpenSync, the manager responsible for the Public WiFi-related operations is the Public WiFi Manager (PWM). PWM evokes the dedicated GRE channels to forward the client traffic to the gateway node. As a result, the private secure WiFi network traffic is separated from the "public" network traffic.

OpenSync provides two AP connection security options: 

  • Open for free and unrestricted user access

  • 802.1x for secure user access

Prerequisites

OpenSync Version

Public WiFi is available with OpenSync 3.4 and later.

End-to-end feature development was done for the Broadcom platforms. Implementation for other platforms can be done per request.

Relevant Northbound API Tables

The below listed OVSDB tables and fields are mandatory to enable Public WiFi.

Table Wifi_VIF_Config. The below listed fields are set only on the Public WiFi VIFs (for other VIFs, the nodes use default values):

  • min_rssi: Signal strength threshold to prevent the distant low RSSI clients from associating with the specified VAPs.

  • max_sta: Limits the number of allowed public clients to be associated with each VAP. 

  • airtime_precedence: Allows setting the percentage for the WiFi airtime per each VAP on the same radio. This helps mitigate traffic congestion on a HaaHs-enabled location.

Table Public_Wifi_Config:

  • vif_ifnames: Defines which VIFs are to be connected to the GRE tunnel. For example, if the internet is out, PWM stops broadcasting the affected SSID. 

Table Wifi_Inet_Config:

  • if_type: Option gre6 allows enabling the GRE tunneling over IPv6.

Passpoint_Config table configures the network and roaming parameters.

The listed tables and their field options are described in https://www.opensync.io/s/EUB-020-033-101_OpenSync_34_Northbound_API.pdf

SSID Prioritization

In Public WiFi networking scenarios, there are always multiple "competing" SSIDs. On the same VAP, private WiFi SSID traffic should always have higher priority than the public WiFi SSID traffic. To achieve this, OpenSync provides air-time management support using Traffic Ordering Agent Daemon (TOAD). 

TOAD is currently supported only on Broadcom platforms.

Requirements

Enabled Public WiFi Manager (PWM)

For the OpenSync-enabled gateway nodes, PWM enables or disables the Public WiFi services. By default, PWM is disabled. This means that Public WiFi requires enabling the PWM during the node startup using Kconfig.