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UID2 Sharing: Overview 

In UID2, sharing is a process for distributing raw UID2s securely between UID2 participants. To protect raw UID2s from unauthorized access, the originating participant (sender) must encrypt the raw UID2s into UID2 tokens before transmission. The destination participant (receiver) must decrypt the UID2 tokens into raw UID2s for internal use.

The UID2 sender specifies which receivers can decrypt their UID2 tokens, by configuring permissions in the UID2 Portal (see UID2 Portal: Overview). When a sender grants permission to a receiver for UID2 sharing, the sender's decryption keys are shared with the receiver via a UID2 SDK. As part of sharing, the UID2 SDKs and APIs take care of the encryption and decryption.

For example, let's say that an advertiser (sender) wants to share raw UID2s with a trusted sharing participant who is a UID2 DSP, for segment creation via an API. Using sharing, the advertiser first enables the DSP with sharing permission via the UID2 Portal. The advertiser then encrypts the raw UID2s into UID2 tokens and sends them securely to the DSP (receiver). The DSP, who is also taking part in sharing, has access to the advertiser's decryption keys (through the UID2 Portal sharing permissions setup), and can therefore decrypt the UID2 tokens into raw UID2s for segment creation.

Both the UID2 sender and receiver must create an account in order to take part in sharing. Without an account, a UID2 participant is not displayed in the list of sharing participants in the UID2 Portal.

There are many scenarios for sharing. For additional examples, see Sharing UID2s: Use Cases.

NOTE: The process for publishers sharing UID2 tokens in the bid stream is a different process. If you are a publisher who is putting UID2 tokens into the bid stream, see Sharing in the Bid Stream.

Additional resources:

UID2 Sharing Workflow

To share UID2 data securely between UID2 participants, which includes encrypting raw UID2s into UID2 tokens that the receiver can decrypt using your encryption keys, you must use a UID2 SDK or the UID2 Snowflake integration.

The workflow for UID2 sharing, for all sharers except when sharing UID2 tokens in the bid stream, consists of the following steps:

  1. Sender and receiver: Integrate with UID2 sharing, using one of the following:

  2. Sender and receiver: Approve sharing permissions in the UID2 Portal:

    1. Sender: Define which sharing participants are allowed to decrypt the sender's UID2 token.
    2. Sender and receiver: Request a UID2 Portal account: see Request an Account.
    3. Sender: Log in to the UID2 Portal and navigate to the sharing permissions page: see Sharing Permissions.
    4. Sender: Select the participants that you want to share with. If needed, use the search feature to find specific sharing participants.
    5. Sender: Save the sharing selection.
  3. Sender: Complete the following steps to encrypt and send the UID2s:

    1. Encrypt raw UID2s to convert them into UID2 tokens, using a UID2 SDK or Snowflake: see Sharing Steps: Summary.
    2. Transmit the UID2 tokens to an authorized receiver.
  4. Receiver: Complete the following steps to decrypt the UID2 tokens:

    1. Receive the UID2 tokens.
    2. Decrypt the UID2 tokens into raw UID2s that the receiver can use: see Sharing Steps: Summary.

The following diagram illustrates the UID2 sharing permission SDK integration workflow:

UID2 Sharing Permission SDK Integration Workflow

Generating the Token for UID2 Sharing: Example

Note: If you are a publisher, see Token Example for Publishers in the Bid Stream.

UID2 sharers follow a two-step process, as shown in the following example. The steps are:

  1. Convert email or phone number to raw UID2:

    Convert the input email address or phone number to a raw UID2, which they can store securely.

  2. Convert raw UID2 to UID2 token:

    Encrypt the raw UID2 to create a UID2 token that they can share with another trusted UID2 sharing participant.

Input ExampleProcess/UserResult
user@example.comConvert email/phone number to raw UID2:
POST /identity/map endpoint
Encrypt raw UID2 to create a UID2 token:
encrypt() function in applicable SDK. For example, for Java, see Usage for UID2 Sharers step 3.

Sharing in the Bid Stream

The process for publishers sharing UID2 tokens in the bid stream is a different process. For details, see Sharing in the Bid Stream.

UID2 Token Pass-Through

The UID2 token is designed so that even if the underlying raw UID2 remains the same, each time a UID2 token is generated from it, the token value is different. This means that the UID2 token can be seen by all but can only be used by UID2 participants that have access to the decryption key.

For example, UID2 tokens are habitually passed through the bid stream from a publisher to a DSP. Although a UID2 token might go through several parties, such as an SSP, it can be decrypted only by an authorized UID2 participant. On its journey through the bid stream, the UID2 token can safely pass through one or more intermediaries.

The same is true in all sharing scenarios between UID2 sharing participants. A UID2 token can be passed through non-UID2 participants.