On March 12 2004, Yossi Vardi, Ami Ben-Bassat, and Guy Vardi sent 3 homing pigeons from a distance of 100 kilometres (62 mi), each carrying 20-22 tiny memory cards (Msystems' Disk-On-Chip) containing 1.3 GB, amounting in total of 4 GB of data, achieving an effective throughput of 2.27 Mbps. The purpose of the test was to measure and confirm an improvement over RFC 2549.[10] Since the developers used flash memory instead of paper notes as specified by RFC 2549, the experiment was widely criticized as an example in which an optimized implementation breaks an official standard. [citation needed]