# Manage the correlation engine

Mesh pulls accounts in from every system you connect — your identity provider, HR system, cloud platforms, and infrastructure. The **correlation engine** is what decides when several of those accounts belong to the same person, so Mesh shows you one identity instead of a handful of disconnected accounts.

Correlation runs on a **matching model**. Your organization always has exactly one model active at a time, and that model is what scores every account as it arrives. This page covers how to see which model you are on, how to move to a newer one, and how to request a model trained on your organization's own data.

## Before you start

- You need administrator access to **System configurations**.
- The correlation engine is enabled per organization by Axiad. If you do not see a **Correlation Engine** card under System configurations → General, contact Axiad Support.
- Tenant-specific training is being rolled out gradually and is enabled separately. If the **Request Tenant-Specific Training** button is absent, ask Axiad Support whether it is available for your organization.

## See which model is active

Go to **System configurations → General**. The **Correlation Engine** card shows your **Active model** — for example, `MeshIQ · 1`.

![The Correlation Engine card under System configurations, showing an active model of MeshIQ 1, a Re-Correlate / Change Model button, and a Training column with a Request Tenant-Specific Training button](/img/correlation-engine/correlation-engine-card.png)

If tenant-specific training is not enabled for your organization, the card shows the active model and the re-correlate action only.

![The same Correlation Engine card without the Training column, showing only the active model and the Re-Correlate / Change Model button](/img/correlation-engine/correlation-engine-card-no-training.png)

> **note**
Accounts are collected continuously whether or not correlation is active. If you see a banner saying correlation is not active for your organization yet, your data is still being ingested — it is simply not being matched into identities until a model is active. That banner should clear within a day of setup. If it persists beyond that, contact Axiad Support rather than waiting, because your risk picture stays incomplete until it clears.

## Re-correlate or change your model

Re-correlating rebuilds every identity link in your organization from scratch using the model you select. Use it when Axiad releases a newer model you want to adopt, or when you want a clean rebuild on your current model.

1. On the **Correlation Engine** card, select **Re-Correlate / Change Model**.
2. Choose a model. The dropdown defaults to your current model — leaving it unchanged re-runs correlation on that same model rather than migrating you to a new one.
3. Read **What happens when you re-correlate**, then select all four acknowledgements.
4. Under **When**, choose **Run Now** or **Schedule** and pick a date and time.
5. Select **Confirm & Run**.

![The Re-Correlate / Change Model dialog showing the model dropdown set to MeshIQ 1 (Current) and a panel explaining what happens when you re-correlate](/img/correlation-engine/re-correlate-model-and-disclosure.png)

The four acknowledgements confirm that you understand:

| Acknowledgement | What it means |
| --- | --- |
| Consent to re-correlation | You authorize the use of this tenant's identity data to run a full re-correlation using the selected model. |
| Existing correlations will be removed | All current identity correlation links are deleted and rebuilt. This begins immediately on confirmation. |
| Scoring will be recalculated | All identity match scores are recomputed. Scores currently in use by downstream systems will change. |
| Model change confirmed | You intend to change the active model, and this affects all users in the tenant. |

![The lower half of the Re-Correlate dialog showing the four acknowledgement checkboxes and the Run Now or Schedule options](/img/correlation-engine/re-correlate-acknowledgements-and-schedule.png)

> **caution**
Re-correlation cannot be reversed once it starts. It re-evaluates your entire identity history, so for a large organization it can take a while. Start it at a time when you do not need to make other identity changes.

### What you see while it runs

The **Re-Correlate / Change Model** button is unavailable while the process runs. There is no progress percentage. When it finishes, the **Active model** badge updates to the model you selected and a **Migration Completed** badge appears beside it — dismiss that badge with the **×** once you have seen it.

![The Correlation Engine card after a completed migration, showing an active model of MeshIQ 3 and a dismissible Migration Completed badge](/img/correlation-engine/migration-completed.png)

### What changes afterward

- **Identity counts can change.** Accounts that were previously grouped together may split apart, and separate accounts may merge, as the new model re-evaluates your data.
- **Risk scores are recalculated** to match the new grouping. A total or aggregate risk figure moving after a re-correlation reflects more accurate grouping, not lost data. See [risk scoring](/docs/concepts/risk-scoring).
- **Your team's decisions are preserved.** Matches your analysts have confirmed or rejected are respected and are not silently overridden.

## Request a model trained on your data

Every organization's identity data looks different — naming conventions, employee ID formats, service account patterns. A tenant-specific model is trained on your own data so matching is tuned to those patterns.

1. On the **Correlation Engine** card, select **Request Tenant-Specific Training**.
2. Read **How your data is used**.
3. Select all five acknowledgements, then select **Submit Request**.

![The Request Tenant-Specific Training dialog showing a data-use disclosure and five consent checkboxes](/img/correlation-engine/request-tenant-training.png)

### How your data is used

The tenant data listed in the dialog is read by the machine-learning algorithm only. It is never sent to any external party. Results are written back to your tenant database, and the source data is not retained after training completes. The data read is:

- Users table (primary)
- Related identity attribute tables, as required

This processing is performed solely to improve correlation accuracy for your organization. Axiad does not use your data to train shared or global models.

### After you submit

Axiad reviews every training request before it runs. While a request is pending, the button is unavailable and the card shows **Pending Axiad Ops Approval**. You cannot submit another request until the current one is resolved.

![The Correlation Engine card showing a Pending Axiad Ops Approval badge with the Request Tenant-Specific Training button disabled](/img/correlation-engine/training-pending-approval.png)

| Status | What it means |
| --- | --- |
| Pending Axiad Ops Approval | Submitted and awaiting review. |
| Training Request Rejected | Not approved. A reason is shown alongside the status. |
| Training Scheduled | Approved and queued. |
| Training Running | Your model is being trained. |
| Training Completed | Your model is ready. |
| Training Failed | Contact Axiad Support. |

Most trainings complete within a few business days of approval.

> **caution**
Training completing does not switch your organization onto the new model. Once it is ready, run a **Re-Correlate / Change Model** and select the new model to start using it.

To withdraw consent, contact Axiad Support **before training begins**. Once training has started it runs to completion.

## How it works

**Models are versioned.** Axiad trains and publishes matching models in a numbered series — `MeshIQ · 1`, `MeshIQ · 2`, and later versions. Newer versions are made available to your organization as they are released, but you are never moved onto one automatically.

**Exactly one model is active at a time.** That active model scores every account as it is ingested, and it keeps doing so regardless of whether you have ever run a re-correlation. Adopting a newer model is always an explicit action.

**Organizations move independently.** Your organization can stay on an older model while another moves to a newer one. There is no requirement to stay in step with anyone else.

**MeshIQ (AI-based correlation engine) supersedes the previous engine.** All new ingestion — new accounts and new data on existing accounts — is already scored by the newer engine. Your existing correlations stay as the previous engine produced them until you re-correlate onto a MeshIQ model. Every organization moves onto a MeshIQ model eventually.

For the underlying concepts, see [identities](/docs/concepts/identities) and [entities](/docs/concepts/entities).

## Troubleshooting

| Symptom | Cause | Resolution |
| --- | --- | --- |
| No **Correlation Engine** card under System configurations → General | The correlation engine is not enabled for your organization. | Contact Axiad Support. |
| Banner says correlation is not active, still showing after a day | Setup did not complete for your organization. | Contact Axiad Support — accounts are being collected but not matched until this clears. |
| No **Request Tenant-Specific Training** button | Tenant-specific training is not yet enabled for your organization. | Contact Axiad Support to ask about availability. |
| Active model unchanged long after starting a re-correlation | Large organizations take longer, and there is no progress indicator to distinguish running from stalled. | Contact Axiad Support, who can check the actual status. |
| Training shows completed but matching looks unchanged | A completed model is not active until you re-correlate onto it. | Run **Re-Correlate / Change Model** and select the new model. |
| Identity counts or risk scores moved after re-correlating | Expected — the new model regrouped accounts and scores were recomputed. | Review the affected identities. Confirmed and rejected matches are preserved. |