2. Monitoring and Observability: Envoyer provides basic monitoring capabilities to track deployments and server performance but does not offer advanced observability features. In contrast, Istio includes robust monitoring and observability tools, allowing users to gain insights into traffic flow, latency, errors, and other metrics within the service mesh.

3. Load Balancing: Envoyer does not provide native load balancing features and relies on the underlying infrastructure for load distribution. Istio, however, offers sophisticated load balancing functionalities, enabling traffic shifting, fault tolerance, and circuit breaking within the service mesh.

4. Traffic Management: Istio allows for advanced traffic management capabilities such as A/B testing, canary deployments, and blue-green deployments, providing granular control over traffic routing and version switching. Envoyer, on the other hand, focuses more on simplifying deployment workflows and does not offer the same level of traffic management features.

5. Security: Istio enhances security in microservices architecture by providing features like mutual TLS authentication, access control, and encryption of communication between services. Envoyer, while offering basic security measures, does not provide the comprehensive security features present in Istio's service mesh.

6. Scalability and Extensibility: Istio is highly scalable and extensible, allowing users to integrate additional functionalities and customize policies through its open-source ecosystem. Envoyer, while suitable for deployment management, may not provide the same level of scalability and extensibility as Istio for complex microservices architectures.

In Summary, Envoyer simplifies deployment management, while Istio focuses on traffic management, monitoring, load balancing, security, scalability, and extensibility within a service mesh architecture.