The END: a network adapter design tool

We present the design and implementation of the Emulated Network Device (END), a network adapter design tool that facilitates accurate evaluation of alternative adapter designs. Using device emulation, the END permits designers to couple a representative model of an adapter with a real host and its communication software. Different adapter designs can be evaluated and compared accurately in a realistic setting, i.e., while capturing host-adapter concurrency and interaction overheads, before building a prototype. We present the architectural framework adopted by the END and demonstrate its feasibility via a case study of a commercial network adapter. Several design improvements to alleviate performance bottlenecks are realized and evaluated using the END, highlighting its utility as a network adapter design tool