Forwarding

Forwarding is the process of moving something from one point to another according to predefined rules. It is used across several domains, including computer networks, email systems, telephony, web infrastructure, and logistics.

In networking, forwarding refers to delivering a received data packet to its next-hop interface based on the routing table. Routers make forwarding decisions to move packets toward their destination, while routing concerns the selection of the best path. Forwarding is a fast, data-plane operation, whereas routing involves control-plane calculations and updates. Network address translation and techniques such as port forwarding map external addresses or ports to internal devices, enabling access from outside a local network.

In email systems, forwarding automatically or manually redirects a received message to a different mailbox. Forwarding can preserve the original headers and sender information, but it can affect deliverability and security. SPF, DKIM, and DMARC considerations may arise when messages are forwarded.

In telephony, call forwarding diverts an incoming call to another number or to voicemail. Common modes include unconditional forwarding, conditional forwarding (when busy or no answer), and per-call rules set by users or organizations.

In the web, URL forwarding or redirects send a client from one URL to another, typically via HTTP 3xx status codes. Redirects are used for site restructuring, load balancing, or shortening long URLs.

In logistics, freight forwarding coordinates the shipment of goods across borders, handling documentation, customs, and carrier arrangements. A freight forwarder acts as an intermediary rather than a carrier.

Security and privacy considerations apply across domains, as forwarding can create exposure if misconfigured or misused.