Transparent network driver
Containers attached to a network created with the 'transparent' driver will be directly connected to the physical network through an external Hyper-V switch. IPs from the physical network can be assigned statically (requires user-specified --subnet option) or dynamically using an external DHCP server.
L2bridge network driver
Containers attached to a network created with the 'l2bridge' driver will be connected to the physical network through an external Hyper-V switch. In l2bridge, container network traffic will have the same MAC address as the host due to Layer-2 address translation (MAC re-write) operation on ingress and egress. In datacenters, this helps alleviate the stress on switches having to learn MAC addresses of sometimes short-lived containers. L2bridge networks can be configured in 2 different ways
https://docs.microsoft.com/en-us/virtualization/windowscontainers/container-networking/network- drivers-topologies