The Realtek RTL8019AS is an older Ethernet controller chip developed by Realtek Semiconductor Corp. It was widely used in the late 1990s and early 2000s to provide network connectivity to various computer systems, particularly desktop PCs and early networking cards.

The RTL8019AS supports 10 Mbps Ethernet, adhering to the IEEE 802.3 standard for Ethernet networks. It features a 16-bit ISA interface, which was common at the time for connecting peripheral devices to the motherboard of PCs.

While the RTL8019AS was once a popular choice for providing basic networking capabilities, it has since been surpassed by faster and more advanced Ethernet controllers, such as the RTL8139 series, which offered 100 Mbps speeds and better performance.

Due to its age and limited capabilities, the RTL8019AS is no longer commonly used in modern computing systems. Instead, it serves as a historical reference to the early days of network connectivity and the advancements made in Ethernet technology over the years.