Networks are composed of links that operate at different bandwidth. When a router needs to forward the packets received from a high-speed link to a lower speed one. In this case, the packets are queued in the buffer before being transmitted on the low speed link.
- Let us consider two routers :
- an upstream router
- a downstream router
The link between the upstream and the downstream router operates at 10 Mbps. The downstream router forwards the packets received from the upstream router over a 1 Mbps link.