Add aussie_broadband documentation (#18948)

Co-authored-by: Franck Nijhof <frenck@frenck.nl>
Co-authored-by: Brett Adams <Bre77@users.noreply.github.com>
Co-authored-by: J. Nick Koston <nick@koston.org>

source/_integrations/aussie_broadband.markdown

@@ -0,0 +1,45 @@
+---
+title: Aussie Broadband
+description: Instructions on how to integrate Aussie Broadband within Home Assistant.
+ha_category:
+- Network
+- Sensor
+ha_release: 2022.2
+ha_iot_class: Cloud Polling
+ha_config_flow: true
+ha_codeowners:
+- '@nickw444'
+- '@Bre77'
+ha_domain: aussie_broadband
+ha_platforms:
+- sensor
+---
+
+The Aussie Broadband integration displays various service metrics using the [Aussie Broadband API](https://myaussie-api.aussiebroadband.com.au).
+
+## Prerequisites
+
+You must have a [My Aussie Broadband](https://my.aussiebroadband.com.au) account, and at least 1 active service.
+
+{% include integrations/config_flow.md %}
+
+## Entities
+
+### Sensor
+
+The integration will create sensor entities for a variety of metrics that relate to your service:
+
+#### NBN/Internet Services
+- Total Usage
+- Downloaded Data
+- Uploaded Data
+- Billing Cycle Length
+- Billing Cycle Remaining
+
+#### Mobile Phone
+- Data Usage
+- National Calls
+- Mobile Calls
+- SMS Sent
+- Billing Cycle Length
+- Billing Cycle Remaining