To offer services to other companies using AWS without traversing the internet, creating a VPC Endpoint Service hosted behind an Application Load Balancer (ALB) and making it available over AWS Direct Connect (DX) is the most suitable solution. This approach ensures that the service traffic remains within the AWS network, adhering to the requirement that connectivity must not traverse the internet. An ALB is capable of handlingHTTP/HTTPS traffic, making it appropriate for web-based services. Utilizing DX for connectivity between the on-premises data center and AWS further secures and optimizes the network path.

AWS Direct Connect Documentation: Explains how to set up DX for private connectivity between AWS and an on-premises network.

Amazon VPC Endpoint Services (AWS PrivateLink) Documentation: Provides details on creating and configuring endpoint services for private, secure access to services hosted in AWS.

AWS Application Load Balancer Documentation: Offers guidance on configuring ALBs to distribute HTTP/HTTPS traffic efficiently.