Switching Via Memory First generation routers: traditional computers with switching under direct control of CPU Opacket copied to system's memory speed limited by memory bandwidth(2 bus crossings per datagram) Input Memory Output Port Port System Bus Network Layer 4-24Network Layer 4-24 Switching Via Memory First generation routers:  traditional computers with switching under direct control of CPU packet copied to system’s memory  speed limited by memory bandwidth (2 bus crossings per datagram) Input Port Output Port Memory System Bus