# Public broadcast satellite utilizing a dataflow endpoint (narrowband)
This example builds off the analysis done in the [JPSS-1 - Public broadcast satellite (PBS) - Evaluation](examples.md#examples.pbs-definition) section of the user guide.
To complete this example, you'll need to assume a scenario -- you want to capture the HRD communication path as digital intermediate frequency (DigIF) and process it as it's received by a dataflow endpoint application on an Amazon EC2 instance using an SDR.
## Communication paths
This section represents [Plan your dataflow communication paths](getting-started.step2.md) of getting started. For this example, you will be creating two sections in your CloudFormation template: Parameters and Resources sections.
**Note**
For more information about the contents of a CloudFormation template, see [ Template sections](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/template-anatomy.html).
For the Parameters section, you're going to add the following parameters. You'll specify values for these when creating the stack via the CloudFormation console.
```
Parameters:
EC2Key:
Description: The SSH key used to access the EC2 receiver instance. Choose any SSH key if you are not creating an EC2 receiver instance. For instructions on how to create an SSH key see [https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/create-key-pairs.html](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/create-key-pairs.html)
Type: AWS::EC2::KeyPair::KeyName
ConstraintDescription: must be the name of an existing EC2 KeyPair.
ReceiverAMI:
Description: The Ground Station DDX AMI ID you want to use. Please note that AMIs are region specific. For instructions on how to retrieve an AMI see [https://docs.aws.amazon.com/ground-station/latest/ug/dataflows.ec2-configuration.html#dataflows.ec2-configuration.amis](https://docs.aws.amazon.com/ground-station/latest/ug/dataflows.ec2-configuration.html#dataflows.ec2-configuration.amis)
Type: AWS::EC2::Image::Id
```
**Note**
You **need** to create a key pair, and provide the name for the Amazon EC2 `EC2Key` parameter. See [ Create a key pair for your Amazon EC2 instance](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/create-key-pairs.html).
Additionally, you'll **need** to provide the correct **region specific** AMI ID, when creating the CloudFormation stack. See [AWS Ground Station Amazon Machine Images (AMIs)](dataflows.ec2-configuration.md#dataflows.ec2-configuration.amis).
The remaining template snippets belong in the Resources section of the CloudFormation template.
```
Resources:
# Resources that you would like to create should be placed within the resource section.
```
Given our scenario to deliver a single communication path to an EC2 instance, you'll have a single synchronous delivery path. Per the [Synchronous data delivery](getting-started.step2.md#getting-started.step2.sync-data-delivery) section, you must set up and configure an Amazon EC2 instance with a dataflow endpoint application, and create one or more dataflow endpoint groups.
```
# The EC2 instance that will send/receive data to/from your satellite using AWS Ground Station.
ReceiverInstance:
Type: AWS::EC2::Instance
Properties:
DisableApiTermination: false
IamInstanceProfile: !Ref GeneralInstanceProfile
ImageId: !Ref ReceiverAMI
InstanceType: m5.4xlarge
KeyName: !Ref EC2Key
Monitoring: true
PlacementGroupName: !Ref ClusterPlacementGroup
SecurityGroupIds:
- Ref: InstanceSecurityGroup
SubnetId: !Ref ReceiverSubnet
BlockDeviceMappings:
- DeviceName: /dev/xvda
Ebs:
VolumeType: gp2
VolumeSize: 40
Tags:
- Key: Name
Value: !Join [ "-" , [ "Receiver" , !Ref "AWS::StackName" ] ]
UserData:
Fn::Base64:
|
#!/bin/bash
exec > >(tee /var/log/user-data.log|logger -t user-data -s 2>/dev/console) 2>&1
echo `date +'%F %R:%S'` "INFO: Logging Setup" >&2
GROUND_STATION_DIR="/opt/aws/groundstation"
GROUND_STATION_BIN_DIR="${GROUND_STATION_DIR}/bin"
STREAM_CONFIG_PATH="${GROUND_STATION_DIR}/customer_stream_config.json"
echo "Creating ${STREAM_CONFIG_PATH}"
cat << STREAM_CONFIG > "${STREAM_CONFIG_PATH}"
{
"ddx_streams": [
{
"streamName": "Downlink",
"maximumWanRate": 4000000000,
"lanConfigDevice": "lo",
"lanConfigPort": 50000,
"wanConfigDevice": "eth1",
"wanConfigPort": 55888,
"isUplink": false
}
]
}
STREAM_CONFIG
echo "Waiting for dataflow endpoint application to start"
while netstat -lnt | awk '$4 ~ /:80$/ {exit 1}'; do sleep 10; done
echo "Configuring dataflow endpoint application streams"
python "${GROUND_STATION_BIN_DIR}/configure_streams.py" --configFileName "${STREAM_CONFIG_PATH}"
sleep 2
python "${GROUND_STATION_BIN_DIR}/save_default_config.py"
exit 0
# The AWS Ground Station Dataflow Endpoint Group that defines the endpoints that AWS Ground
# Station will use to send/receive data to/from your satellite.
DataflowEndpointGroup:
Type: AWS::GroundStation::DataflowEndpointGroup
Properties:
ContactPostPassDurationSeconds: 180
ContactPrePassDurationSeconds: 120
EndpointDetails:
- Endpoint:
Name: !Join [ "-" , [ !Ref "AWS::StackName" , "Downlink" ] ] # needs to match DataflowEndpointConfig name
Address:
Name: !GetAtt ReceiverInstanceNetworkInterface.PrimaryPrivateIpAddress
Port: 55888
SecurityDetails:
SecurityGroupIds:
- Ref: "DataflowEndpointSecurityGroup"
SubnetIds:
- !Ref ReceiverSubnet
RoleArn: !GetAtt DataDeliveryServiceRole.Arn
# The security group for your EC2 instance.
InstanceSecurityGroup:
Type: AWS::EC2::SecurityGroup
Properties:
GroupDescription: AWS Ground Station receiver instance security group.
VpcId: !Ref ReceiverVPC
SecurityGroupIngress:
# To allow SSH access to the instance, add another rule allowing tcp port 22 from your CidrIp
- IpProtocol: udp
FromPort: 55888
ToPort: 55888
SourceSecurityGroupId: !Ref DataflowEndpointSecurityGroup
Description: "AWS Ground Station Downlink Stream"
# The security group that the ENI created by AWS Ground Station belongs to.
DataflowEndpointSecurityGroup:
Type: AWS::EC2::SecurityGroup
Properties:
GroupDescription: Security Group for AWS Ground Station registration of Dataflow Endpoint Groups
VpcId: !Ref ReceiverVPC
SecurityGroupEgress:
- IpProtocol: udp
FromPort: 55888
ToPort: 55888
CidrIp: 10.0.0.0/8
Description: "AWS Ground Station Downlink Stream To 10/8"
- IpProtocol: udp
FromPort: 55888
ToPort: 55888
CidrIp: 172.16.0.0/12
Description: "AWS Ground Station Downlink Stream To 172.16/12"
- IpProtocol: udp
FromPort: 55888
ToPort: 55888
CidrIp: 192.168.0.0/16
Description: "AWS Ground Station Downlink Stream To 192.168/16"
# The placement group in which your EC2 instance is placed.
ClusterPlacementGroup:
Type: AWS::EC2::PlacementGroup
Properties:
Strategy: cluster
ReceiverVPC:
Type: AWS::EC2::VPC
Properties:
CidrBlock: "10.0.0.0/16"
Tags:
- Key: "Name"
Value: "AWS Ground Station - PBS to dataflow endpoint Example VPC"
- Key: "Description"
Value: "VPC for EC2 instance receiving AWS Ground Station data"
ReceiverSubnet:
Type: AWS::EC2::Subnet
Properties:
# Ensure your CidrBlock will always have at least one available IP address per dataflow endpoint.
# See https://docs.aws.amazon.com/vpc/latest/userguide/subnet-sizing.html for subent sizing guidelines.
CidrBlock: "10.0.0.0/24"
Tags:
- Key: "Name"
Value: "AWS Ground Station - PBS to dataflow endpoint Example Subnet"
- Key: "Description"
Value: "Subnet for EC2 instance receiving AWS Ground Station data"
VpcId: !Ref ReceiverVPC
# An ENI providing a fixed IP address for AWS Ground Station to connect to.
ReceiverInstanceNetworkInterface:
Type: AWS::EC2::NetworkInterface
Properties:
Description: Floating network interface providing a fixed IP address for AWS Ground Station to connect to.
GroupSet:
- !Ref InstanceSecurityGroup
SubnetId: !Ref ReceiverSubnet
# Attach the ENI to the EC2 instance.
ReceiverInstanceInterfaceAttachment:
Type: AWS::EC2::NetworkInterfaceAttachment
Properties:
DeleteOnTermination: false
DeviceIndex: "1"
InstanceId: !Ref ReceiverInstance
NetworkInterfaceId: !Ref ReceiverInstanceNetworkInterface
```
In addition, you'll also need to create the appropriate policies and roles to allow AWS Ground Station to create an elastic network interface (ENI) in your account.
```
# AWS Ground Station assumes this role to create/delete ENIs in your account in order to stream data.
DataDeliveryServiceRole:
Type: AWS::IAM::Role
Properties:
Policies:
- PolicyDocument:
Statement:
- Action:
- ec2:CreateNetworkInterface
- ec2:DeleteNetworkInterface
- ec2:CreateNetworkInterfacePermission
- ec2:DeleteNetworkInterfacePermission
- ec2:DescribeSubnets
- ec2:DescribeVpcs
- ec2:DescribeSecurityGroups
Effect: Allow
Resource: '*'
Version: '2012-10-17'
PolicyName: DataDeliveryServicePolicy
AssumeRolePolicyDocument:
Version: 2012-10-17
Statement:
- Effect: Allow
Principal:
Service:
- groundstation.amazonaws.com
Action:
- sts:AssumeRole
# The EC2 instance assumes this role.
InstanceRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Version: "2012-10-17"
Statement:
- Effect: "Allow"
Principal:
Service:
- "ec2.amazonaws.com"
Action:
- "sts:AssumeRole"
Path: "/"
ManagedPolicyArns:
- arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess
- arn:aws:iam::aws:policy/service-role/AmazonEC2ContainerServiceforEC2Role
- arn:aws:iam::aws:policy/CloudWatchAgentServerPolicy
- arn:aws:iam::aws:policy/service-role/AmazonEC2RoleforSSM
# The instance profile for your EC2 instance.
GeneralInstanceProfile:
Type: AWS::IAM::InstanceProfile
Properties:
Roles:
- !Ref InstanceRole
```
## AWS Ground Station configs
This section represents [Create configs](getting-started.step3.md) of getting started.
You'll need a *tracking-config* to set your preference on using autotrack. Selecting *PREFERRED* as autotrack can improve the signal quality, but it isn't required to meet the signal quality due to sufficient JPSS-1 ephemeris quality.
```
TrackingConfig:
Type: AWS::GroundStation::Config
Properties:
Name: "JPSS Tracking Config"
ConfigData:
TrackingConfig:
Autotrack: "PREFERRED"
```
Based on the communication path, you'll need to define an *antenna-downlink* config to represent the satellite portion, as well as a *dataflow-endpoint* config to refer to the dataflow endpoint group that defines the endpoint details.
```
# The AWS Ground Station Antenna Downlink Config that defines the frequency spectrum used to
# downlink data from your satellite.
SnppJpssDownlinkDigIfAntennaConfig:
Type: AWS::GroundStation::Config
Properties:
Name: "SNPP JPSS Downlink DigIF Antenna Config"
ConfigData:
AntennaDownlinkConfig:
SpectrumConfig:
Bandwidth:
Units: "MHz"
Value: 30
CenterFrequency:
Units: "MHz"
Value: 7812
Polarization: "RIGHT_HAND"
# The AWS Ground Station Dataflow Endpoint Config that defines the endpoint used to downlink data
# from your satellite.
DownlinkDigIfEndpointConfig:
Type: AWS::GroundStation::Config
Properties:
Name: "Aqua SNPP JPSS Downlink DigIF Endpoint Config"
ConfigData:
DataflowEndpointConfig:
DataflowEndpointName: !Join [ "-" , [ !Ref "AWS::StackName" , "Downlink" ] ]
DataflowEndpointRegion: !Ref AWS::Region
```
## AWS Ground Station mission profile
This section represents [Create mission profile](getting-started.step4.md) of getting started.
Now that you have the associated configs, you can use them to construct the dataflow. You'll use the defaults for the remaining parameters.
```
# The AWS Ground Station Mission Profile that groups the above configurations to define how to
# uplink and downlink data to your satellite.
SnppJpssMissionProfile:
Type: AWS::GroundStation::MissionProfile
Properties:
Name: "37849 SNPP And 43013 JPSS"
ContactPrePassDurationSeconds: 120
ContactPostPassDurationSeconds: 60
MinimumViableContactDurationSeconds: 180
TrackingConfigArn: !Ref TrackingConfig
DataflowEdges:
- Source: !Ref SnppJpssDownlinkDigIfAntennaConfig
Destination: !Ref DownlinkDigIfEndpointConfig
```
## Putting it together
With the above resources, you now have the ability to schedule JPSS-1 contacts for synchronous data delivery from any of your onboarded AWS Ground Station [AWS Ground Station Locations](aws-ground-station-antenna-locations.md).
The following is a complete CloudFormation template that includes all resources described in this section combined into a single template that can be directly used in CloudFormation.
The CloudFormation template named `AquaSnppJpssTerraDigIF.yml` is designed to give you quick access to start receiving digitized intermediate frequency (DigIF) data for the Aqua, SNPP, JPSS-1/NOAA-20, and Terra satellites. It contains an Amazon EC2 instance and the required CloudFormation resources to receive raw DigIF direct broadcast data.
If Aqua, SNPP, JPSS-1/NOAA-20, and Terra are not onboarded to your account, see [Onboard satellite](getting-started.step1.md).
**Note**
You can access the template by accessing the customer onboarding Amazon S3 bucket using valid AWS credentials. The links below use a regional Amazon S3 bucket. Change the `us-west-2` region code to represent the corresponding region of which you want to create the CloudFormation stack in.
Additionally, the following instructions use YAML. However, the templates are available in both YAML and JSON format. To use JSON, replace the `.yml` file extension with `.json` when downloading the template.
To download the template using AWS CLI, use the following command:
```
aws s3 cp s3://groundstation-cloudformation-templates-us-west-2/AquaSnppJpssTerraDigIF.yml .
```
You can view and download the template in the console by navigating to the following URL in your browser:
```
https://s3.console.aws.amazon.com/s3/object/groundstation-cloudformation-templates-us-west-2/AquaSnppJpssTerraDigIF.yml
```
You can specify the template directly in CloudFormation using the following link:
```
https://groundstation-cloudformation-templates-us-west-2.s3.us-west-2.amazonaws.com/AquaSnppJpssTerraDigIF.yml
```
**What additional resources does the template define?**
The `AquaSnppJpssTerraDigIF` template includes the following additional resources:
+ (Optional) **CloudWatch Event Triggers** - AWS Lambda Function that is triggered using CloudWatch Events sent by AWS Ground Station before and after a contact. The AWS Lambda Function will start and optionally stop your Receiver Instance.
+ (Optional) **EC2 Verification for Contacts** - The option to use Lambda to set up a verification system of your Amazon EC2 instance(s) for contacts with SNS notification. It is important to note that this may incur charges depending on your current usage.
+ **Ground Station Amazon Machine Image Retrieval Lambda** - The option to select what software is installed in your instance and the AMI of your choice. The software options include `DDX 2.6.2 Only` and `DDX 2.6.2 with qRadio 3.6.0`. These options will continue to expand as additional software updates and features are released.
+ **Additional mission profiles** - Mission profiles for additional public broadcast satellites (Aqua, SNPP, and Terra).
+ **Additional antenna-downlink configs** - Antenna downlink configs for additional public broadcast satellites (Aqua, SNPP, and Terra).
The values and parameters for the satellites in this template are already populated. These parameters make it easy for you to use AWS Ground Station immediately with these satellites. You do not need to configure your own values in order to use AWS Ground Station when using this template. However, you can customize the values to make the template work for your use case.
**Where do I receive my data?**
The dataflow endpoint group is set up to use the receiver instance network interface that part of the template creates. The receiver instance uses a dataflow endpoint application to receive the data stream from AWS Ground Station on the port defined by the dataflow endpoint. Once received, the data is available for consumption via UDP port 50000 on the loopback adapter of the receiver instance. For more information about setting up a dataflow endpoint group, see [ AWS::GroundStation::DataflowEndpointGroup](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-groundstation-dataflowendpointgroup.html).