Netstack is a userspace TCP/IP network stack and interfaces with magenta network drivers. Netstack serves as a back-end for mxio socket API.
+-----------+ +-----------+
| FIDL app | | POSIX app |
+------+----+ +-----+-----+
| |
+-------v--------------+ |
| FIDL network service | |
| (//apps/network) | |
+-------+--------------+ |
| |
+-----v--------------------v-----+
| BSD socket API |
| (//magenta/system/ulib/mxio) |
+---------------+----------------+
|
+-------------v--------------+
| netstack |
| (//apps/netstack) |
+-------------+--------------+
|
+----------------v-----------------+
| Ethernet driver |
| (//magenta/system/udev/ethernet) |
+----------------------------------+