In the context of setting up a virtual machine, e1000 emulates an Intel NIC, rtl8139 emulates a Realtek NIC, and virtio is a para-virtualized driver, i.e. it "knows" it's operating in a VM and basically just passes the network traffic between the VM and the host in the most straightforward way possible.
Rtl8139.sys is a Windows driver. A driver is a small software program that allows your computer to communicate with hardware or connected devices. This means that a driver has direct access to the internals of the operating system, hardware etc.The free file information forum can help you determine if rtl8139.sys is a Windows system file or if it belongs to an application that you can trust.
The process known as Realtek RTL8139 NDIS (version 5.0 Driver) or NDIS 5.0 driver belongs to software Realtek RTL8139(A/B/C)-based PCI Fast Ethernet Adapter NT Driver or NT-Treiber für Realtek RTL8139(A/B/C)-basierten PCI-Fast Ethernetadapter by Realtek Semiconductor (www.realtek.com.tw).
Description: The original rtl8139.sys is an important part of Windows and rarely causes problems. Rtl8139.sys is located in the C:\Windows\System32\drivers folder.Known file sizes on Windows 10/8/7/XP are 20,992 bytes (90% of all occurrences) or 23,070 bytes. The driver can be started or stopped from Services in the Control Panel or by other programs.The file is a Windows core system file. The program has no visible window. The service has no detailed description. It is a trustworthy file from Microsoft.rtl8139.sys appears to be a compressed file.Therefore the technical security rating is 4% dangerous, however you should also read the user reviews.
Important: Some malware disguises itself as rtl8139.sys, particularly when not located in the C:\Windows\System32\drivers folder. Therefore, you should check the rtl8139.sys process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World. 2b1af7f3a8