Port mirroring is used on a network switch to forward a copy of a packet received on one interface (source), to another interface (destination) on the same switch. This helps in monitoring network traffic where both ingress and egress packets are forwarded to another host. In the current implementation, the packet can be forwarded to multiple monitor (destination) interfaces.
The implementation in SEFOS allows up to four independent port mirroring sessions on a switch, with each session having one source interface, a primary destination interface, and a maximum of three secondary interfaces.