1. Supported Platforms: AWS Elemental MediaTailor primarily supports VOD (Video on Demand) content and live streaming, while JW Player is designed for streaming video and audio across various devices and platforms, including desktop, mobile, and OTT devices.

2. Monetization Options: AWS Elemental MediaTailor offers server-side ad insertion capabilities, allowing for targeted advertisements and personalized content delivery, whereas JW Player provides a variety of monetization options including advertising from multiple sources, paywalls, and subscription services.

3. Integration Capabilities: AWS Elemental MediaTailor seamlessly integrates with other AWS services such as AWS CloudFront, AWS Elemental MediaPackage, and Amazon CloudFront CDN, while JW Player offers integration with popular advertising networks, analytics platforms, and content management systems for a more customized video experience.

4. Content Protection: AWS Elemental MediaTailor provides built-in content protection features such as DRM (Digital Rights Management) integration, secure token-based authentication, and SSL encryption, whereas JW Player offers robust security protocols and options for content protection including DRM integration and token authentication.

5. Analytics and Reporting: AWS Elemental MediaTailor offers advanced analytics and reporting tools for monitoring ad impressions, user engagement, and viewing behavior, while JW Player provides detailed analytics on video performance, viewer behavior, and engagement metrics to optimize content delivery and monetization strategies.

6. Customization and Branding: JW Player allows for extensive customization of the player interface, branding options, and player skins to match the look and feel of the website or application, while AWS Elemental MediaTailor focuses more on delivering seamless ad experiences and targeted content delivery without extensive customization options for the player interface.

In Summary, the key differences between AWS Elemental MediaTailor and JW Player lie in their supported platforms, monetization options, integration capabilities, content protection features, analytics and reporting tools, and customization and branding options.