hostapd software package provides IEEE 802.11 AP and IEEE 802.1X/WPA/WPA2/EAP Authenticator, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install hostapd
hostapd is installed in your system.
Make ensure the hostapd package were installed using the commands given below,
$ sudo dpkg-query -l | grep hostapd *
You will get with hostapd package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Network |
| Package | hostapd |
| Version | 1:2.5-2+v2.4-3+b1 |
| Description | IEEE 802.11 AP and IEEE 802.1X/WPA/WPA2/EAP Authenticator |
| Sub Section | Net |