As with other classes of devices, Ersatz-11 uses a device-independent interface to attach any supported PC network interface type as the physical side of any supported PDP-11 network interface type. Each interface is created using a one-line ASSIGN command in the E11.INI initialization text file. E11 can optionally perform filtering based on Ethernet protocol numbers so that the PDP-11 operating system will not be swamped by broadcast traffic intended for other systems. Note that while real PDP-11 network interfaces were limited to 10 MBPS Ethernet, E11 will work with the newer high-speed Ethernet interfaces.

Physical PC network interfaces: (E11 for DOS)

• Any Ethernet interface with a packet driver
• Via Velocity-based PCI Ethernet cards
• RealTek RTL8169-based PCI Ethernet cards
• RealTek RTL8139-based PCI Ethernet cards
• AMD PCnet-PCI-based PCI Ethernet cards
• DEC Tulip-based PCI Ethernet cards
• NE2000 clones, ISA or PCI (built-in driver)
• Point-to-point Internet using UDP tunneling

Physical PC network interfaces: (E11 for Windows)

• Any Ethernet (or Ethernet-like) interface supported by Windows
• Point-to-point Internet using UDP tunneling

E11 needs the (free) WinPcap package to perform raw Ethernet I/O

Physical PC network interfaces: (E11 for Linux)

• Any Ethernet (or Ethernet-like) interface supported by Linux
• Point-to-point Internet using UDP tunneling

E11's network driver requires version 2.2 or later of the Linux kernel

Emulated PDP-11 network interfaces:

dev name	controller types	description
NI:	Interlan NI1010A/NI2010A	Unibus/Q-bus Ethernet port
XE:/NU:	DEUNA, DELUA	Unibus Ethernet port
XH:/NQ:	DEQNA, DELQA	Q-bus Ethernet port

As of V7.0, Ersatz-11 also emulates synchronous ports which implement DEC's proprietary DDCMP protocol in microcode or firmware. E11's internal DDCMP layer can use any supported serial device for the physical connection, and will interconnect with DEC's own asynchronous DDCMP drivers.

Emulated PDP-11 DDCMP interfaces:

dev name	controller types	description
XM:	DMC11, DMR11	Unibus synchronous DDCMP port