Interopware supplies an Amazon Machine Image in all the regions of the world called "Network Echo Server".
Almost all customer endpoint locations, such as a remote office, home office, a factory, or a sensor are connected to the Internet with more than one Internet Service Provider. When there are multiple ISP links, it is also necessary for the device if the Internet is reachable through each link. A typical approach is to ping a well-known endpoint and most devices are configured to continuously ping a public DNS server. However that approach does not guarantee the reachability of your own cloud VPC. Typically you would have to deploy an compute instance (AWS EC2 for example)
Network Echo Server v1.0.0 provides a very simple service. It listens on UDP port 7777 and replies back whenever a UDP packet is received from any client.
This server is supplied as an Amazon Machine Image and can be deployed on any AWS region.
Deploy the Network Echo Server from the AMI
Configure DNS entries and Elastic IP addresses optionally. We highly recommend the use of Elastic IP addresses.
Configure the security group to allow incoming port 7777 with both IPv4 and IPv6 source addresses.
Have your client program send an UDP packet on port 7777 with a simple string payload and await a response to ensure connectivity. When there are multiple ISP links, it is natural to have two client programs, each bound to its own ISP link.
When there is no response received within a given timeout, the client program is free to redirect packets from the endpoint location to the working link.
Future versions of the Network Echo Server will support additional features
the Echo service using additional protocols, such as IP, TCP, HTTP, QUIC, SIP, NTP etc.
Pingback to send ping packets back useful for hole punching use cases
Responses will also contain data related to packet latency