Streamer is a paid Esper service that acts as a proxy server. It handles Esper Agent app download traffic and provides two static IP addresses.
We offer streamer service to accommodate customers uncomfortable with allowing relatively wide-open *.amazonaws.com FQDN.
Streamer is not enabled on every tenant. Contact Esper to enable streamer for your tenant or go to your Tenant Settings > Firewall Settings to enable it.
Once enabled, you can set up the following firewall rule in place of *.amazonaws.com :
FQDN | Port |
streamer.esper.io | TCP: 443 (HTTPS) |