GDA App – Field Activation

The GDA (Ground-level Device Activator) is an Android application used once during the initial setup of each physical site. It discovers all ONVIF-compatible cameras on the local network and automatically configures event forwarding to the GC Surge cloud—no manual per-camera configuration required. Covers: What the GDA App Does, Platform support, How WS-Discovery Works.

What the GDA App Does

After activation is complete, the GDA app plays no ongoing role. Cameras communicate directly with the cloud ingest endpoint, and the app can be uninstalled.

Platform support

Android
iOS support is not yet available.
Supported brands for automatic configuration — Hikvision, Dahua, Axis, and NX Witness. Hanwha and Spike Box cameras run on the NX Witness platform — select NxWitness.

How WS-Discovery Works

WS-Discovery (Web Services Dynamic Discovery) is the standard ONVIF protocol for discovering devices on a local network. When the GDA app initiates discovery, it sends a UDP multicast broadcast to the local subnet (address 239.255.255.250). ONVIF-compatible cameras that receive the broadcast respond with their service endpoint address. The app collects all responses and presents the discovered cameras for your review. For discovery to work, the following conditions must be met:

The Android device and cameras must be on the same network segment (same subnet or VLAN).
UDP multicast must not be blocked by the network switch or router.
ONVIF must be enabled on each camera. This is enabled by default on most modern cameras.

Before You Start

Before running the GDA app, confirm the following:

Install the GDA (Ground-level Device Activator) app on your Android device before arriving on site. Download it from Google Play.
Your Android device is connected to the same local network as the cameras — same Wi-Fi network or switched Ethernet segment.
All cameras are powered on and connected to the network.
You have received the Site Key from your administrator.
ONVIF is enabled on each camera — if you are unsure, see If Cameras Are Not Discovered below.

How You Receive the Site Key

Your administrator sends the Site Key from the Configuration. It is delivered in one of three ways:

WhatsApp link — tap the link on your Android device. If the GDA app is installed, it opens automatically with the Site Key pre-filled.
Email — the email contains the full Site Key (GCSK-...) for manual entry, and a deep link that opens the GDA app with the key pre-filled if the app is already installed. If the deep link does not pre-fill the key, the GDA app may be out of date — update the app and try again, or enter the key manually.
QR code — if the administrator is on-site with you, scan the QR code directly from the Configuration. The app opens with the key pre-filled.

Network Requirements

The GDA app discovers cameras using multicast broadcasts, which means the Android device and cameras must be able to communicate on the same network segment. Different network setups require different preparation:

Flat network (recommended): All cameras and the Android device are on the same Wi-Fi or Ethernet network. Discovery works automatically with no additional configuration.
VLAN-segmented network: If cameras are on a separate VLAN from the Android device, WS-Discovery will not reach them. Options: temporarily connect the Android device to the camera VLAN during activation, have your IT team configure multicast routing between VLANs, or enter camera IP addresses manually in the app.
Multiple subnets at one location: Each subnet must be activated separately. Connect the Android device to each subnet in turn and run discovery for each.

Activation Steps

Open the GDA app on your Android device.
Enter the Site Key — type it manually, tap the WhatsApp link your administrator sent to pre-fill it automatically, or scan the QR code if your administrator is present on site.
Tap Discover and wait for the camera list to load.
Review the discovered camera list and confirm it matches the number of cameras at the site. If cameras are missing, see If Cameras Are Not Discovered below.
Tap Activate. The app configures event forwarding on each discovered camera automatically — no per-camera steps required.
Wait for the success confirmation before leaving the site.

If Cameras Are Not Discovered

If cameras do not appear in the discovery results, ONVIF may be disabled on the camera. Enable it through the camera's web interface:

Hikvision

Log in to the camera web interface. Go to Configuration → Network → Advanced Settings → Integration Protocol. Enable ONVIF.

Dahua

Log in to the camera web interface. Go to Setting → System → Account and confirm an ONVIF user is configured. Then go to Setting → Network → Advanced Settings and enable ONVIF.

AXIS

ONVIF is enabled by default. No action is usually required.

If a camera still does not appear after enabling ONVIF, confirm that the camera and the Android device are on the same network segment.

What the App Configures on Each Camera

For each discovered camera, the GDA app automatically pushes SMTP event forwarding settings. You do not need to enter these manually — the app retrieves the correct credentials from the GC Surge cloud using your Site Key and injects them directly into each camera.

The following is configured on each camera:

SMTP server: smtp.zeptomail.eu
SMTP port: 587
Encryption: TLS.
Authentication credentials: unique to this site, retrieved from the cloud using the Site Key.
Sender address: alerts@nxgen.io
Receiver: the GC Surge ingest address specific to this site, assigned automatically.
Image attachments: enabled — each alarm event includes a camera snapshot.
Send interval: minimum 5 seconds between alarm emails.

After Activation: Verifying the Pipeline

After the GDA app completes, allow up to 10 minutes for the cloud to finish pushing settings. In Configuration, open the site and check the cameras’ Configuration status — it should move from pending to Created (not Error). The site’s own Status shows Active as soon as it is added, so that is not a sign that configuration finished. Then verify that alarms are reaching the platform:

Generate a test event at the site — trigger motion detection or walk through the camera's field of view.
Wait 30–60 seconds.
In GC Surge, go to Video Search.
Select the newly activated site.
Confirm the test event appears as an event card.

If no events appear after 5 minutes

Check that the camera has outbound internet access to smtp.zeptomail.eu on port 587.
Verify that motion or detection triggers are enabled on the camera.
Check the camera's clock — incorrect timestamps can cause events to be processed out of order.
Log into the camera's web interface and use the built-in Test button in the email or SMTP settings to send a test email directly.

Error Messages

The GDA app displays an error message for every failure. If anything goes wrong at any step — scanning the QR code, authenticating with the cloud, discovering cameras, or injecting configuration — the app shows the specific error on screen. Share a screenshot of the error with your administrator or support team for faster resolution.

Edge Deployment Mode — Ongoing Operation

When the GDA app is used for an Edge deployment, it does not play a one-time role. The app must stay running on the Android device continuously — it is the alarm engine for that site. Closing or removing the app stops alarm forwarding from all cameras at that site.

In Edge mode, the app pulls the RTSP stream directly from each camera on the local network, runs NOVA99x classification on-device, and forwards only the classified events to GC Surge. No alarm reaches the cloud before on-device filtering.

Edge App Features

Live stream view — shows the live RTSP feed from cameras on the local network. This is the device-side live view only (not a general GC Surge cloud stream — see ZenMode for alarm review).
Device health monitoring — displays real-time status of the edge device: RAM usage, CPU load, and uptime. Use this to confirm the device is healthy enough to sustain continuous processing. A heavily loaded device may drop frames or delay alarm forwarding.
Arm / Disarm — toggles alarm forwarding on or off for the site. When disarmed, the app continues running and streaming locally but stops sending alarms to GC Surge. Use disarm during planned maintenance or false-alarm investigations, then re-arm when monitoring should resume.
Camera area masking — draw exclusion zones on the camera view directly from the app. Masked areas are excluded from event detection at the edge level, before NOVA99x classification. Useful for permanently noisy zones such as trees, roads, or flags in the camera field of view.
Alarm logs — the app maintains a local log of all events detected and forwarded. Useful for confirming the site is receiving alarms and for troubleshooting forwarding gaps without logging into GC Surge.
ZenMode access — operators at the site can open ZenMode directly from within the GDA app to review and close alarms without switching to the web platform.

Device Requirements for Continuous Edge Operation

The Android device must remain powered on and connected to the local camera network at all times.
Battery-powered devices must be connected to a charger — continuous RTSP processing drains the battery rapidly.
The device should not be used for other applications while running as an edge node — CPU and RAM are consumed by the stream processing.