#### [Abblix\.Oidc\.Server](https://www.abblix.com/en/docs/api/abblix-oidc-server 'index')
### [Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.Interfaces](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.Interfaces')

## IBackChannelRequestStorage Interface

Defines the contract for a storage system responsible for persisting and retrieving
backchannel authentication requests in the context of Client\-Initiated Backchannel Authentication \(CIBA\)\.

```csharp
public interface IBackChannelRequestStorage
```

Derived  
↳ [BackChannelRequestStorage](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelRequestStorage 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.BackChannelRequestStorage')
### Methods

## IBackChannelRequestStorage\.StoreAsync\(BackChannelAuthenticationRequest, TimeSpan\) Method {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.StoreAsync(Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan)}

Asynchronously stores a backchannel authentication request in the storage system\.
This method saves the provided authentication request and sets its expiration based on the specified duration\.

```csharp
System.Threading.Tasks.Task<string> StoreAsync(Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest authenticationRequest, System.TimeSpan expiresIn);
```
#### Parameters

###### `authenticationRequest` [BackChannelAuthenticationRequest](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.BackChannelAuthenticationRequest') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.StoreAsync(Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan).authenticationRequest}

The backchannel authentication request to store\.

###### `expiresIn` [System\.TimeSpan](https://learn.microsoft.com/en-us/dotnet/api/system.timespan 'System\.TimeSpan') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.StoreAsync(Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan).expiresIn}

The duration after which the stored request will expire\.

#### Returns
[System\.Threading\.Tasks\.Task&lt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')[System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')  
A task that returns the ID of the stored authentication request\.

## IBackChannelRequestStorage\.TryGetAsync\(string\) Method {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.TryGetAsync(string)}

Tries to retrieve a backchannel authentication request by its unique identifier\.
This method checks if a request exists for the specified ID and returns it if found\.

```csharp
System.Threading.Tasks.Task<Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest?> TryGetAsync(string authenticationRequestId);
```
#### Parameters

###### `authenticationRequestId` [System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.TryGetAsync(string).authenticationRequestId}

The unique identifier of the authentication request to retrieve\.

#### Returns
[System\.Threading\.Tasks\.Task&lt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')[BackChannelAuthenticationRequest](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.BackChannelAuthenticationRequest')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')  
A task that returns the authentication request if found;
otherwise, null\.

## IBackChannelRequestStorage\.TryRemoveAsync\(string\) Method {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.TryRemoveAsync(string)}

Atomically retrieves and removes a backchannel authentication request from storage\.
This operation prevents race conditions where multiple concurrent requests could retrieve the same
authentication request before it's removed \(poll mode double\-retrieval vulnerability\)\.

```csharp
System.Threading.Tasks.Task<Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest?> TryRemoveAsync(string authenticationRequestId);
```
#### Parameters

###### `authenticationRequestId` [System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.TryRemoveAsync(string).authenticationRequestId}

The unique identifier of the authentication request to remove\.

#### Returns
[System\.Threading\.Tasks\.Task&lt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')[BackChannelAuthenticationRequest](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.BackChannelAuthenticationRequest')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')  
A task that returns the authentication request if it existed and was successfully removed;
otherwise, null if the request was not found or already removed\.

## IBackChannelRequestStorage\.UpdateAsync\(string, BackChannelAuthenticationRequest, TimeSpan\) Method {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.UpdateAsync(string,Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan)}

Updates an existing backchannel authentication request in storage\.
Used in ping mode to update request status when user completes authentication\.

```csharp
System.Threading.Tasks.Task UpdateAsync(string requestId, Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest request, System.TimeSpan expiresIn);
```
#### Parameters

###### `requestId` [System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.UpdateAsync(string,Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan).requestId}

The unique identifier of the authentication request to update\.

###### `request` [BackChannelAuthenticationRequest](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.BackChannelAuthenticationRequest') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.UpdateAsync(string,Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan).request}

The updated authentication request data\.

###### `expiresIn` [System\.TimeSpan](https://learn.microsoft.com/en-us/dotnet/api/system.timespan 'System\.TimeSpan') {#Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage.UpdateAsync(string,Abblix.Oidc.Server.Features.BackChannelAuthentication.BackChannelAuthenticationRequest,System.TimeSpan).expiresIn}

The duration after which the request expires\.

#### Returns
[System\.Threading\.Tasks\.Task](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task 'System\.Threading\.Tasks\.Task')  
A task that completes when the request is updated in storage\.