1. Communication Protocols: Armeria primarily focuses on asynchronous communication using various protocols like HTTP/2, gRPC, and WebSocket, while Lagom Framework emphasizes using the Akka Cluster for communication between services.
2. Concurrency Models: Armeria leverages Netty for its high-performance non-blocking I/O tasks, enabling efficient handling of a large number of concurrent connections, whereas Lagom Framework utilizes the actor model provided by Akka for managing concurrency.
3. Service Discovery: Armeria offers built-in support for service discovery using platforms like Zookeeper, Consul, and Etcd, facilitating easy service registration and discovery, while Lagom Framework uses the Lightbend ConductR tool for service discovery and management.
4. Persistence Support: Armeria does not provide built-in support for persistence mechanisms and database integration, requiring external libraries for such functionalities, whereas Lagom Framework integrates with Akka Persistence and Cassandra for persistent storage and event sourcing.
5. Programming Languages: Armeria is primarily developed in Java and Kotlin, providing compatibility with the JVM ecosystem, while Lagom Framework is built on the Scala programming language, offering strong integration with Akka and Play Framework.
6. Community and Ecosystem: Armeria has a rapidly growing community with contributors from various organizations like LINE and Google, focusing on building microservices at scale, whereas Lagom Framework has a well-established community backed by Lightbend, offering comprehensive support and resources for developers.

In Summary, the key differences between Armeria and Lagom Framework lie in their communication protocols, concurrency models, service discovery, persistence support, programming languages, and community ecosystem.