tussenserver

A tussenserver, literally an intermediate server, is a server that acts as an intermediary between a client and a target server or network. It receives requests from clients, processes or forwards them, and then returns responses to the client. Tussenservers are deployed to manage, secure, or optimize communications in many network environments, from corporate IT to public services.

Common forms include forward proxies, which sit between client devices and the wider Internet, and reverse proxies, which stand in front of one or more internal services to handle incoming requests. In addition, gateways, API gateways, load balancers, caching proxies, and content filters all function as tussenservers in various configurations. Some deployments combine several roles in a single device or service.

Typical functions of a tussenserver include forwarding requests, caching frequently requested content to reduce bandwidth and latency, performing load balancing across backend servers, terminating TLS connections, authenticating users, enforcing access control policies, filtering content, translating between protocols, and collecting logging and telemetry data for monitoring and auditing.

Deployment considerations include the location in the network (for example, between the internal network and the Internet or in a DMZ), redundancy and failover, and the risk that a misconfigured tussenserver can become a single point of failure or a target for attacks. Privacy and data protection concerns arise because intermediaries can inspect or modify traffic, so proper configuration, encryption, and access controls are essential.

Because the term is used in Dutch IT contexts, English-language sources may refer to related concepts as proxies, gateways, or middleboxes.