Prevent and address cyber attacks and disruptions

Room bombing refers to one or more users maliciously disrupting the order of a channel. It usually occurs in chat rooms and other multi-user interactive use cases. Common patterns include intercepting a token, repeatedly joining with a long-lived token, continuously making noise or sending illegal audio or video content, hijacking signaling messages, or reconnecting after a network interruption.

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Agora strongly recommends token authentication for your app. Token authentication ensures that only authorized users can join a channel and controls the user's streaming privileges. To use token authentication, integrate token generation into your business server and enable token verification on the Agora server. See Secure authentication with tokens for details.

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

When a token is about to expire, the SDK triggers the token-expiry callback, such as onTokenPrivilegeWillExpire. When you receive this callback, obtain a fresh token from the token server and call renewToken to pass the new token to the SDK.

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Regularly call the Agora RESTful API http://api.sd-rtn.com/dev/v1/channel/user/{appid}/{channelName}/{hosts_only} on the app server to query the Agora server's online channel user list, and compare it with the user list maintained on the app server to find illegal users. The API call frequency is capped at 20 times per second.

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of Voice SDK for Web. Visit the SDKs page and download the latest SDK.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with tokenExpirationInSeconds and privilegeExpirationInSeconds.

Update tokens regularly

When a token is about to expire, Voice SDK for Web triggers the token-privilege-will-expire callback. When you receive this callback, obtain a fresh token from the token server and call renewToken to pass the new token to the SDK.

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `join` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `join` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken`, and call `setClientRole` to switch the role to host.

Response plan

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call setMuted(true) on the local audio track to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel.

Reference

Channel Management RESTful API
token-privilege-will-expire
renewToken
setClientRole

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Response plan

Agora recommends that you implement the preventive measures in the basic security plan before taking the following response steps.

Locate illegal users

Handle illegal users

After you identify an illegal user, stop their disruptive behavior to restore order to the room. Use one or more of the following methods:

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

This page describes measures that help maintain room order and improve business security.

Basic security solutions

Use the latest SDK version

To ensure that you have the latest security updates, upgrade to the latest version of the Voice SDK. Visit the SDKs page and download the latest SDK for your platform.

Use token authentication

Set an appropriate validity period for tokens and permissions

To prevent unauthorized users from joining a channel by taking advantage of long token validity, set a suitable validity period with these token generation parameters:

tokenExpirationInSeconds: Sets the validity timestamp of the token. The default and maximum validity period is 24 hours. Best practice is to set the validity period as short as possible while meeting business needs.
privilegeExpirationInSeconds: Sets the effective timestamp of the permission. After the permission expires, the user is removed from the channel, and unauthorized users cannot use the token to log in again.

Update tokens regularly

Agora recommends setting tokenExpirationInSeconds and privilegeExpirationInSeconds to the same value.

Store the app ID and app certificate securely on your app server. If you suspect leakage, switch to a new primary certificate.

When updating the app certificate, choose a time when the number of online users is at a minimum to avoid large-scale login failures.

Use co-host token authentication

For use cases where audience members frequently go on and off the microphone, Agora provides authentication for users who publish streams in a channel. This is known as co-host token authentication.

Before using this feature, make sure you have enabled Co-host token authentication in Agora Console.

To use co-host token authentication, set the user role with the role parameter when generating a token, and set the expiration time of all privileges with privilegeExpirationInSeconds.

Role and use case	Authentication steps
Host joins the channel to send streams	Request a token with `role` set to `kRolePublisher`, call `setClientRole` to set the role as host, and call `joinChannel` with a token that has streaming privileges.
Audience member joins the channel	Request a token with `role` set to `kRoleSubscriber`. Because a user's role is audience by default when joining a channel, call `joinChannel` directly with the token.
Audience member gets the mic after joining	Request a token with `role` set to `kRolePublisher`, call `renewToken` to update the token on the Agora server, and call `setClientRole` to switch the role to host.

After implementing co-host authentication, use it together with your business logic to verify that the user's ID is legitimate and that the user is authorized to broadcast streams.

Ask the user's client to call muteLocalAudioStream and set muted to true to stop publishing the audio stream.
Ask the user's client to call setClientRole to set the user's role as audience and cancel streaming privileges.
Call http://api.sd-rtn.com/dev/v1/kicking-rule from the app server to kick the user out of the channel. Configure the cname and uid fields in the join_channel privileges to decide whether to block a channel, a user, or a specific user in a specific channel.

Reference

Channel Management RESTful API
renewToken
setClientRole
muteRemoteAudioStream

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