In a method for dynamic buffer adjustment at a line card of router, a current buffer occupancy at the line card is compared with at least a first buffer occupancy threshold, the first buffer occupancy threshold being calculated based on a buffer occupancy threshold parameter and a capacity of at least a first buffer memory at the line card; and an active buffer capacity is adjusted by at least one of activating and deactivating buffer memory blocks at the line card based on the comparing step, the activating including switching on the buffer memory blocks, and the deactivating including causing the buffer memory blocks to enter a sleep state.