Entry node definition
In networking, an entry node is a point of entry into a specific system. An entry node serves as the initial contact point for data packets entering the network from the internet or some other external source.
Entry nodes are particularly important for trusted proxy setups because the operator of the entry node can see the user’s real IP address. For example, in the context of The Onion Router (Tor) network, an entry node is the first node that receives the user’s traffic. In virtual private networks (VPN), an entry node is the initial point through which a user’s traffic enters the VPN tunnel.
How entry nodes work
Entry nodes are often situated within a network’s demilitarized zone (DMZ) —a separate network segment that acts as a buffer between the internal network and an external one (such as the internet). Entry nodes receive the incoming data and make a decision on how to route it through the network.
In some cases, an entry node may distribute incoming traffic across multiple internal resources to balance the server load. Entry nodes are also equipped with security mechanisms (such as firewall rules or intrusion detection systems) to prevent malicious actors from infiltrating the network.