Amazon SPN (Service Provider Network) is Amazon’s directory of third-party service providers that sellers can hire for imaging, cataloguing, A+ content, ads, account management and more. Each must meet Amazon’s criteria for the service it’s listed in. Sellers compare ratings and reviews, then contract with a provider directly.
In India the directory sits on Amazon’s Seller Central, and anyone can browse it. When a seller sends a provider a request from its listing, it reaches the provider through Amazon’s SPN portal. Amazon lists providers that meet its criteria, but it doesn’t endorse any of them, so it’s worth reading a provider’s listing and reviews before you hire.