Cisco ASR1000-ESP100-X= Network Interface Processor Networking

With these line cards, the ASR 1000 Series routers can achieve greater Ethernet density and a lower price per port. However, this fixed configuration means that the Ethernet line cards are not compatible with the Shared Port Adapters (SPAs) that are currently used with the SPA interface processors. Instead, the Ethernet line cards take the slot of the SPA interface processor.