# Setting Up IVS Private Channels Setting Up Private ChannelsSetting Up Private Channels Added "How Session Protection Works."Setting Up Private Channels In "Create or Import a Playback Key," reorganized content and clarified use of private and public keys. In "Generate and Sign Playback Tokens," clarified that you do not have to enter the public key in jwt.io.Setting Up Private Channels In "Token Schema," added information about support for multiple domains and wildcard domains in the `access-control-allow-origin` token-payload field.Setting Up Private Channels Added a new section, "Workflow for Private Channels." In the section on generating and signing tokens, clarified payload field descriptions and example. Corrected examples for listing and getting playback key pairs.Setting Up Private Channels New User Guide page on new Amazon IVS functionality, supporting private channels. This also affects several existing documents: [Getting Started with Amazon IVS](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/getting-started.html) and [Logging Amazon IVS API Calls with AWS CloudTrail](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/cloudtrail.html): Added `authorized` field to channel. [Security](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/security.html): Several changes including a new section on “Privileged and Unprivileged Access.” [Service Quotas](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/service-quotas.html): Added several playback quotas. [Glossary](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/ivs-glossary.html): Added playback key pair. Amazon Interactive Video Service (IVS) offers customers the ability to create private channels, allowing customers to restrict their streams by channel or viewer. Customers control access to video playback by enabling *playback authorization* on channels and generating signed JSON Web Tokens (JWTs) for authorized playback requests. Requiring playback authorization on a channel is optional. When a viewer tries to watch a stream, if the channel has authorization enabled, Amazon IVS verifies that the viewer has a valid playback token in the request. A playback token is a JWT that the Amazon IVS customer signs (with a playback authorization key) and includes with every playback request for a channel that has playback authorization enabled. **Topics** + [ # How Session Protection Works ](private-channels-session-protection.md) + [ # Workflow for IVS Private Channels ](private-channels-workflow.md) + [ # Create or Import an IVS Playback Key ](private-channels-create-key.md) + [ # Enable Playback Authorization on IVS Channels ](private-channels-enable-playback-auth.md) + [ # Generate and Sign IVS Playback Tokens ](private-channels-generate-tokens.md) + [ # List IVS Playback Keys ](private-channels-list-keys.md) + [ # Delete IVS Playback Keys ](private-channels-delete-keys.md) + [ # Get Information about IVS Playback Keys ](private-channels-get-info.md) + [ # Revoke IVS Viewer Sessions ](private-channels-start-session-revocation.md) # How Session Protection Works How Session Protection Works When you request a playback URL with a valid playback token, IVS creates an authorized session and returns playlist and segment URLs that are unique to that session. These subsequent URLs do not contain a visible token parameter, but they are still tied to the authorized session. Mechanisms are in place to mitigate sharing of session-bound URLs while still allowing legitimate usage patterns (e.g., mobile users switching between WiFi and cellular). If IVS detects unnatural usage, the authorized session is revoked and playback stops for all clients using that session. # Workflow for IVS Private Channels Workflow for Private Channels This diagram illustrates the workflow for setting up IVS private channels: ![\[The workflow for private channels: using a network request from the browser to fetch tokens.\]](http://docs.aws.amazon.com/ivs/latest/LowLatencyUserGuide/images/Private_Channels_Workflow.png) 1. When a viewer tries to load the webpage for a private stream, the browser requests an access token. (The customer provides the browser code to do this.) 1. The customer’s backend app receives the access-token request and determines whether that viewer should be authorized to view the stream. If yes, the backend generates a JWT, uses the customer’s private key to sign it, and returns the signed JWT in a playback request to the browser. 1. The browser loads the stream, using a request to the Amazon IVS player (or other player) SDK. The request contains the stream playback URL and the signed JWT. 1. Amazon IVS uses the customer’s public key to verify that the JWT was signed using the correct private key. 1. If the JWT is verified, Amazon IVS plays the private stream for the viewer. Customers are responsible for creating: + The browser code to request access tokens. + The backend server app that generates and signs JWTs. + A playback authorization key pair. This has two parts: a public key that AWS retains and a private key that you download. With the private key, you sign the JWTs that authorize access to your private channel. The method described above — using a network request from the browser to fetch tokens — is not the only way to implement playback authorization. Alternately, customers could send the signed playback tokens in the initial webpage, to reduce the number of network round trips that a viewer needs to make. In the sections below, we describe how to make a channel private (enable playback authorization), generate and sign playback tokens, and work with playback key pairs. **Note:** In the console instructions below, if the left navigation menu is not displaying, you can open it by choosing the hamburger icon in the top left. # Create or Import an IVS Playback Key Create or Import a Playback Key Amazon IVS allows a maximum of three key pairs that can be used to sign and verify playback tokens. Amazon IVS does not offer any key rotations. ***Once imported, playback keys cannot be updated.*** Instead, you must delete the existing playback key and import a new key. You need to generate an [ECDSA public/private key pair](https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm) to sign the JWTs and upload the public key to Amazon IVS as a playback-key resource. Then Amazon IVS can verify the signature in playback requests. ## Creating a New Key Pair There are various ways to create a key pair; below, we give two examples. ### Console Instructions To create a new key pair in the console, follow these steps. Note this process enables you to download only the private key. 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the left navigation menu, choose **Playback security > Playback keys**. 1. Choose **Create playback key**. A **Create playback key** dialog appears. 1. Enter a name for the playback key and choose **Create**. 1. Amazon IVS generates a new key pair. The public key of this pair is saved to your AWS account and will be used to verify any playback requests that contain a token signed with the private key. The private key is immediately downloaded to your machine and is not saved in the console or available for future download. ***Be sure you save the private key; you cannot retrieve it later.*** ### OpenSSL Instructions **Note:** You may have to install [OpenSSL](https://www.openssl.org/source/) before following these instructions. To create a new P384 EC key pair with OpenSSL, follow these steps. This process enables you to access both the private and public keys. You need the public key only if you want to test verification of your tokens. ``` openssl ecparam -name secp384r1 -genkey -noout -out priv.pem openssl ec -in priv.pem -pubout -out public.pem ``` Now import your new public key, using the instructions below. ## Importing an Existing Public Key If you already have a key pair, you can import the public key into IVS. The private key is not needed by our system but is employed by you to sign tokens. ### Console Instructions To import an existing public key with the console: 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the left navigation menu, choose **Playback security > Playback keys**. 1. Choose **Import**. An **Import playback key** dialog appears. 1. Give the imported key a name, and browse for the public key file (or paste the public key file contents), then choose **Import**. 1. Amazon IVS imports your public key and generates a playback key resource. ### CLI Instructions To import an existing public key with the CLI: ``` aws ivs import-playback-key-pair --public-key-material "`cat public.pem`" --region ``` You can omit `--region ` if the region is in your local AWS configuration file. Here is an example response: ``` { "keyPair": { "arn": "arn:aws:ivs:us-west-2:693991300569:playback-key/f99cde61-c2b0-4df3-8941-ca7d38acca1a", "fingerprint": "98:0d:1a:a0:19:96:1e:ea:0a:0a:2c:9a:42:19:2b:e7", "tags": {} } } ``` ### API Request For usage information, see [ImportPlaybackKeyPair](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_ImportPlaybackKeyPair.html) in the *IVS Low-Latency Streaming API Reference*. ``` POST /ImportPlaybackKeyPair HTTP/1.1 { "publicKeyMaterial": "" } ``` # Enable Playback Authorization on IVS Channels Enable Playback Authorization on Channels A channel’s authorization requirement can be configured when the channel is created or later (using an update operation). Note that the steps are the same whether you want to enable or disable playback authorization. Note that playback restriction policies (such as geo-blocking) cannot be used simultaneously with playback authorization. If playback authorization is enabled for a channel, any configured playback restriction policies will be ignored. To enforce geo-restrictions on a private channel, validate the user's location within your token generation logic before issuing a playback token. ## Console Instructions To enable authorization when creating a channel: 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the **Get started** box (top right), choose **Create channel**. 1. On the **Channel create** page, choose **Custom configuration**. 1. In the **Playback authentication** section, turn on **Enable token-authentication requirement for video playback**. 1. Follow the rest of the prompts to create a channel. (See [Getting Started with IVS Low-Latency Streaming](getting-started.md).) To enable authorization by updating an existing channel: 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the left navigation menu, choose **Channels**. 1. Choose the checkbox for the channel you want to update, then choose **Edit**. 1. In the **Playback authentication** section, turn on **Enable token-authentication requirement for video playback**. 1. Click **Save changes**. ## CLI Instructions To enable authorization when creating a channel: ``` aws ivs create-channel --authorized --region ``` You can omit `--region ` if the region is in your local AWS configuration file. Here is an example response. Note that `authorized` is `true`. ``` { "streamKey": { "channelArn": "arn:aws:ivs:us-west-2:123456789:channel/fbc789c1-2c56-4ce6-a30a-d99275dc4481", "value": "sk_us-west-2_abcd1234efgh5678ijkl", "arn": "arn:aws:ivs:us-west-2:123456789:stream-key/62f15f1b-fe31-4127-b252-0666ac7f55a7", "tags": {} }, "channel": { "name": "test-channel", "tags": {}, "authorized": true, "latencyMode": "LOW", "ingestEndpoint": "jds34ksdg3las.global-contribute.live-video.net", "playbackUrl": "https://b37c565f6d79.us-west-2.playback.live-video.net/api/video/v1/aws.ivs.us-west-2.123456789.channel.oU4OKS4LA1Dz.m3u8", "arn": "arn:aws:ivs:us-west-2:123456789:channel/fbc789c1-2c56-4ce6-a30a-d99275dc4481" } } ``` To enable authorization by updating an existing channel: ``` aws ivs update-channel --arn arn:aws:ivs:us-west-2:693991300569:channel/742da049-fe9f-4f23-928e-c6753760a189 --authorized ``` This is just an example; you must specify your own channel ARN after `--arn`. As when creating a channel, `authorized` is `true` in the update response. ## API Requests (Create and Update) For usage information, see [CreateChannel](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_CreateChannel.html) and [UpdateChannel](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_UpdateChannel.html) in the *IVS Low-Latency Streaming API Reference*. ``` POST /CreateChannel HTTP/1.1 { "name": "", "authorized": true } ``` ``` POST /UpdateChannel HTTP/1.1 { "arn": "", "authorized": true } ``` # Generate and Sign IVS Playback Tokens Generate and Sign Playback TokensSetting Up Private Channels In "Token Schema," updated `access-control-allow-origin` definition to refer to "origin" instead of "domain."Setting Up Private Channels Updated "Generate and Sign Playback Tokens" (information on creating the signature and steps in "Instructions").Setting Up Private Channels In the section on "Generate and Sign Playback Tokens," the `channel-arn` value in the JWT payload is a string.Setting Up Private Channels In the section on "Generate and Sign Playback Tokens,"noted that the `exp` (expiration) field in JWT payloads is an integer. For details on working with JWTs and the supported libraries for signing tokens, visit [jwt.io](https://jwt.io/). On the jwt.io interface, you must enter your private key to sign tokens. The public key is needed only if you want to verify tokens. ## Token Schema All JWTs have three fields: header, payload, and signature. + The **header** specifies: + `alg` is the signing algorithm. This is ES384, an ECDSA signature algorithm that uses the SHA-384 hash algorithm. + `typ` is the token type, JWT. ``` { "alg": "ES384", "typ": "JWT" } ``` + The **payload** contains data specific to Amazon IVS: + `channel-arn` is a reference for the video-playback request. + `access-control-allow-origin` is an optional field that can be used to restrict playback to a specified [origin](https://developer.mozilla.org/en-US/docs/Glossary/Origin); i.e., to make a stream viewable from only a specified website. For example, you may want to prevent people from embedding the player on other websites. By default, playback is allowed on all origins. (Note that this restricts only the browser client; it does not restrict playback from a non-browser client.) This field may contain multiple origins, separated by commas. Wildcard domains are allowed: each origin may begin its hostname with \$1 (example: https://\$1.amazon.com). If `strict-origin-enforcement` is `true`, at most 5 domains may be specified; otherwise, there is no maximum. + `strict-origin-enforcement` is an optional field that can be used to strengthen the origin restriction specified in the `access-control-allow-origin` field. By default, the `access-control-allow-origin` restriction applies only to the multivariant playlist. If `strict-origin-enforcement` is enabled, the server will enforce a requirement that the requesting origin matches the token for all playback requests (including multivariant playlist, variant playlist, and segments). This means that all clients (including non-browser clients) will have to provide a valid origin-request header with each request. Use the `setOrigin` method to set the header in the IVS iOS and Android player SDKs. It is set automatically in web browsers except iOS Safari. For iOS Safari, you need to add `crossorigin="anonymous"` to the video element, to ensure that the origin request header is sent. Example: ``. + `single-use-uuid` is an optional field which contains a valid [universally unique identifier (UUID)](https://en.wikipedia.org/wiki/Universally_unique_identifier) that you generate as part of authoring the token. If you add this field and a UUID value, the associated token that you generate is invalidated once it is used to fetch a multivariant playlist and watch a stream. Single-use auth tokens make it more difficult for malicious users to share a stream on your private channels with other viewers. Note that when using the `single-use-uuid` claim, the maximum value for the `exp` claim is 10 minutes in the future. + `viewer-id` is an optional field which contains an ID used for tracking and referring to the viewer to whom the token is granted. This field is required to enable the ability to revoke the viewing session of the viewer in the future. The maximum length is 40 characters, and the value must qualify as a string. Do not use this field for personally identifying, confidential, or sensitive information. Note that when using `viewer-id`, the maximum value for `exp` is 10 minutes in the future. + `viewer-session-version` is an optional field which contains a version to associate with this viewer session. When revoking viewer sessions, this value can be used to filter which viewer sessions are revoked. For example, specifying a Unix timestamp here would enable revocation of all sessions started before the specified time. The value must be a 64-bit signed integer (Int64). This field is meant to be provided (optionally) alongside `viewer-id`; it does nothing on its own. The default value is 0. + `maximum-resolution` allows you to specify manifest filtering by resolution for a viewer session, based on viewer entitlements. For example, setting this field to `HD` means the viewer will receive a resolution less than or equal to `HD`. + `exp` is a Unix UTC timestamp for when the token expires. This does not indicate the length of time that the stream can be viewed. The token is validated when the viewer initializes playback, not throughout the stream. Enter this value as an integer type value. Note that a Unix timestamp is a numeric value representing the number of seconds from 1970-01-01T00:00:00Z UTC until the specified UTC date/time, ignoring leap seconds. Different languages measure Unix timestamps in different units; e.g., JavaScript’s `Date.now()` returns the time in milliseconds. (See `exp` in the [JWT RFC section 4.1.4](https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.4).) ``` { "aws:channel-arn": "", "aws:access-control-allow-origin": "", "aws:strict-origin-enforcement": true, "aws:single-use-uuid": "", "aws:viewer-id": "", "aws:viewer-session-version": "", "aws:maximum-resolution": "SD" | "HD" | "FULL_HD", "exp": } ``` + To create the **signature**, use the private key with the algorithm specified in the header (ES384) to sign the encoded header and encoded payload. ``` ECDSASHA384( base64UrlEncode(header) + "." + base64UrlEncode(payload), ) ``` ## Instructions 1. Generate the token’s signature with the ES384 signing algorithm and a private key that is associated with one of your playback-key resources (see the `ECDSASHA384` example above). 1. Assemble the token. ``` base64UrlEncode(header) + "." + base64UrlEncode(payload) + "." + base64UrlEncode(signature) ``` 1. Append the signed token to the playback URL as a query parameter. ``` https://b37c565f6d790a14a0e78afaa6808a80.us-west-2.playback.live-video.net/ api/video/v1/aws.ivs.us-west-2.123456789. channel.fbc789c1-2c56-4ce6-a30a-d99275dc4481.m3u8?token= ``` ## Node.js Example Below is one way to generate a token on the back end (via a microservice or serverless application) using Node.js. ``` import jwt from "jsonwebtoken"; const getToken = () => { const privateChannelArn = process.env.DEMO_PRIVATE_CHANNEL_ARN; // private channel ARN const privateChannelPrivateKey = process.env.DEMO_PRIVATE_CHANNEL_PRIVATE_KEY; // playback private key const payload = { "aws:channel-arn": privateChannelArn, "aws:access-control-allow-origin": "*", "exp": Date.now() + (60 * 1000), // expires in 1 minute }; const token = jwt.sign(payload, privateChannelPrivateKey, { algorithm: 'ES384' }); return token; } ``` In your frontend application, you can retrieve this token and append it to the playback URL of the private channel, as shown below. ``` const streamUrl = `https://b37c565f6d790a14a0e78afaa6808a80.us-west-2.playback.live-video.net/api/video/v1/aws.ivs.us-west-2.123456789.channel.fbc789c1-2c56-4ce6-a30a-d99275dc4481.m3u8?token.m3u8?token=${token}` const ivsPlayer = IVSPlayer.create(); ivsPlayer.attachHTMLVideoElement(document.getElementById('video-player')); ivsPlayer.load(streamUrl); ivsPlayer.play(); ``` # List IVS Playback Keys List Playback Keys Amazon IVS customers can get a list of all of their playback-key resources at any time. ## Console Instructions 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the left navigation menu, choose **Playback security > Playback keys**. All playback-key resources associated with your account are displayed. Deleted keys are not displayed, and there is no history of past keys. ## CLI Instructions ``` aws ivs list-playback-key-pairs --region ``` You can omit `--region ` if the region is in your local AWS configuration file. Example response: ``` { "keyPairs": [ { "arn": "arn:aws:ivs:us-west-2:991729659840:playback-key/3db9fc15-df57-4c02-b5a6-d4ee3448b8ad", "fingerprint": "81:f3:8c:88:78:61:4e:bc:58:07:a3:ca:63:f5:72:08", "tags": {} }, { "arn": "arn:aws:ivs:us-west-2:991729659840:playback-key/3ff88c71-b18e-415f-948b-18bbde605a97", "fingerprint": "a2:b5:b3:0b:be:8e:73:00:0e:ad:e9:bb:02:c9:81:9a", "tags": {} } ] } ``` ## API Request For usage information, see [ListPlaybackKeyPairs](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_ListPlaybackKeyPairs.html) in the *IVS Low-Latency Streaming API Reference*. ``` POST /ListPlaybackKeyPairs HTTP/1.1 { "maxResults": number, "nextToken": "string" } ``` # Delete IVS Playback Keys Delete Playback Keys Amazon IVS customers can delete playback keys from their accounts. Deleted keys will remove the resource from the customer’s account; playback tokens signed with deleted keys will not pass verification. ## Console Instructions 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the left navigation menu, choose **Playback security > Playback keys**. 1. Choose the key(s) you want to delete. 1. Choose **Delete**. A **Delete playback key** dialog appears. 1. Choose **Delete playback key**. ## CLI Instructions You can delete playback keys via the AWS CLI, if you have the key’s ARN. Amazon IVS does not support batch deletes via the CLI. ``` aws ivs delete-playback-key-pair --arn arn:aws:ivs:us-west-2:991729659840:playback-key/3db9fc15-df57-4c02-b5a6-d4ee3448b8ad --region ``` You can omit `--region ` if the region is in your local AWS configuration file. On success, there is no response. You can run the `get` command (below) to verify that the key was deleted. Here is an example error response: ``` An error occurred (ResourceNotFoundException) when calling the DeletePlaybackKeyPair operation: ResourceNotFoundException: ``` ## API Request For usage information, see [DeletePlaybackKeyPair](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_DeletePlaybackKeyPair.html) in the *IVS Low-Latency Streaming API Reference*. ``` POST /DeletePlaybackKeyPair HTTP/1.1 { "arn": "" } ``` # Get Information about IVS Playback Keys Get Information about Playback Keys Amazon IVS customers can get information about their playback key resources. It is important to note that the associated private key will not be available, even in the case that the playback key was created by Amazon IVS via the console. ## Console Instructions 1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). Choose your channel’s region if you are not already on it. 1. In the left navigation menu, choose **Playback security > Playback keys**. 1. Choose the key you want to get more details about and choose **View details**. ## CLI Instructions ``` aws ivs get-playback-key-pair --arn arn:aws:ivs:us-west-2:991729659840:playback-key/3db9fc15-df57-4c02-b5a6-d4ee3448b8ad --region ``` You can omit `--region ` if the region is in your local AWS configuration file. Example response: ``` { "keyPair": { "arn": "arn:aws:ivs:us-west-2:991729659840:playback-key/3ff88c71-b18e-415f-948b-18bbde605a97", "fingerprint": "a2:b5:b3:0b:be:8e:73:00:0e:ad:e9:bb:02:c9:81:9a", "tags": {} } } ``` ## API Request For usage information, see [GetPlaybackKeyPair](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_GetPlaybackKeyPair.html) in the *IVS Low-Latency Streaming API Reference*. ``` POST /GetPlaybackKeyPair HTTP/1.1 { "arn": "" } ``` # Revoke IVS Viewer Sessions Revoke Viewer Sessions Amazon IVS customers can revoke the viewer session associated with an auth token, to prevent and stop playback using that token. An example use case is transitioning a public stream to a private stream in which only a subset of the public stream viewers can continue watching. For information on the `viewer-id` field mentioned in the instructions below, see the "Token Schema" under [Generate and Sign IVS Playback Tokens](private-channels-generate-tokens.md). ## CLI Instructions You can revoke the viewer session via the AWS CLI, if you have the channel ARN and the viewer ID. ``` aws ivs start-viewer-session-revocation --channel-arn arn:aws:ivs:us-west-2:991729659840:channel/abcdABCDefgh --viewer-id UDbh1u6M8nrOoarrzuKe --region ``` An optional input, `--viewer-session-versions-less-than-or-equal-to ` lets you specify a filter for which versions of the viewer session to revoke at once. You can omit `--region ` if the region is in your local AWS configuration file. On success, there is no response. Here is an example error response: ``` An error occurred (ValidationException) when calling the StartViewerSessionRevocation operation: ValidationException: ``` ## API Request For usage information, see [StartViewerSessionRevocation](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_StartViewerSessionRevocation.html) in the *IVS Low-Latency Streaming API Reference*. ``` POST /StartViewerSessionRevocation HTTP/1.1 { "channelArn": , "viewerId": , "viewerSessionVersionsLessThanOrEqualTo": } ``` There also is a [BatchStartViewerSessionRevocation](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_BatchStartViewerSessionRevocation.html) operation.