> For the complete documentation index, see [llms.txt](https://docs.mediarithmics.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mediarithmics.io/audience-and-activation/activate-your-audiences/send-your-audience-to-a-destination/extend-your-reach-with-third-party-ids-connect-id.md).
# Extend your reach with third-party ids (Connect ID)
Use third-party identifiers to carry your audience to a partner, when your own identifiers do not reach far enough.
## Your goal
Activate an audience on users your own identifiers cannot address, by sending third-party identifiers instead of - or alongside - your first-party identifiers.
## Expected outcome
A preset whose identifying resources include the third-party identifiers your partner accepts, and an activation whose reach is no longer capped by how many of your users are logged in or cookied.
## When this is useful
Your segment is the right size and the activation still reaches few users. That is usually not a segment problem but an addressability problem: the identifier you are sending is thin. Third-party identifiers exist to close that gap - network IDs, for instance, can reach users in environments that exclude third-party cookies.
## What Connect ID is
**Connect ID** is the mediarithmics identity layer. It connects offline and online identities in a privacy-safe way, and is built on the mediarithmics clean room technology - see [Data Clean Room](https://app.gitbook.com/s/XSPACE_COLLABORATION/#what-a-data-clean-room-is).
Data providers share identifier mappings, and Connect ID builds an identity graph from them. As a buyer, you consume that graph to enrich your activation with digital identifiers beyond your own. Those identifiers are not limited to network IDs: they can be network IDs such as FirstId, mobile IDs, mediarithmics cookies, and others.
{% hint style="info" %}
Connect ID is a product in its own right: you do not need to be a mediarithmics CDP customer to use it. To learn more, contact mediarithmics.
{% endhint %}
## Concepts you need first
Network IDs are one family of third-party identifiers. What they are, the three axes they differ on, and how the platform stores them are documented in [Network IDs](https://app.gitbook.com/s/XSPACE_SETUP/collect-and-manage-your-data/design-your-data-model-and-schema/user-identity/network-ids#what-a-network-id-is), in the **Setup & Monitor** section. Getting a network ID into your graph in the first place - registries, compartments, channel activation - belongs to the **Connect ID** section.
This page covers only the activation-side decision: **which identifiers a preset should send**.
## The identifiers a preset can carry
Beyond your own first-party identifiers, the platform's graph can hold:
* First and third-party cookies
* CRM ids
* Mobile app ids (GAID / IDFA)
* Hashed emails (MD5, SHA-256, and others)
* Telco box IDs
* TV advertising ids
* Network IDs
Which of these a given partner accepts is per partner, is stated on that connector's page in the **Connectors** section, and is shown in the feed's **Identifying resources** section when you configure the preset.
{% hint style="warning" %}
Compatibility is not universal and is not a property of the network ID alone: activation platforms hold specific agreements with network IDs, so you will not be able to activate every network ID on every platform. Check the connector page before promising reach.
{% endhint %}
## Steps
{% stepper %}
{% step %}
### Measure the gap first
Read the identifier coverage on your existing feed - the percentage of UserPoint for which compatible identifiers could be sent. That number, not the segment size, is what a third-party identifier is meant to improve. See [The three numbers that matter](/audience-and-activation/activate-your-audiences/track-a-feed-stats-and-troubleshoot.md#the-three-numbers-that-matter).
{% endstep %}
{% step %}
### Check what the partner accepts
Open the connector's page in the **Connectors** section, and the preset's **Identifying resources** section, to see which identifier types are available for that connector.
{% endstep %}
{% step %}
### Add the identifier to the preset
Identifying resources are configured **at the preset level** and cannot be changed on a feed. Add the third-party identifier there, and every feed using the preset picks it up immediately. See [Identifying resources](/audience-and-activation/activate-your-audiences/set-up-a-destination/preset.md#identifying-resources).
{% endstep %}
{% step %}
### Re-measure
Compare identifier coverage before and after. Interoperability between network IDs means one ID can extend addressability further than its own footprint suggests, so the improvement is worth measuring rather than assuming.
{% endstep %}
{% endstepper %}
## Deciding which network IDs to invest in
The question is not which network ID is best, but which fits your ecosystem. The questions worth answering before contracting with one are in [Choosing which network IDs to integrate](https://app.gitbook.com/s/XSPACE_SETUP/collect-and-manage-your-data/design-your-data-model-and-schema/user-identity/network-ids#choosing-which-network-ids-to-integrate), and the precision-versus-reach trade-off between deterministic and probabilistic IDs is in [What a network ID is](https://app.gitbook.com/s/XSPACE_SETUP/collect-and-manage-your-data/design-your-data-model-and-schema/user-identity/network-ids#what-a-network-id-is), both in the **Setup & Monitor** section.
For more on network IDs and the questions above, contact your Account manager.
## Verification
Identifier coverage on the feed improves, and the audience size reported by the partner rises accordingly. If coverage improves but the partner's figure does not, the constraint is on the partner side - check that the connector and the partner account actually accept the identifier you added.
## Related pages
---
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