I have a shared DSL connection, and I know that some of the users constantly get their computers infected, so I worry about network security. My computer is the only one wired to the modem (which is also the wireless AP) by an Ethernet cable (eth0 interface), every other user is wireless connected (wlan0 interface).
What measures should I take in order to isolate or protect my computer? I know that if one is connected to the wireless network one can intercept and read the packages that are being sent using software such as Wireshark and ettercap, so how could I avoid the reading of the packages I send, or, if that's not possible, what other precautions should I take?
I'm not looking for answers like "you shouldn't share your network with them in the first place", since this is the case both at home (with my roommates) and at work (so I can't do much about it).
Some settings that might be relevant:
On/Auto
NAT
LAN to LAN (intra LAN) multicast
WMM(Wi-Fi Multimedia)
WMM APSD
Client Isolation
Off
Wireless Multicast Forwarding
Support 802.11n Client Only
OBSS Co-Existance
WMM No Acknowledgement
WPS
IGMP Snooping
QoS (quality of service)
LAN side firewall
Other
Network Authentication - mixed wpa2/wpa - psk
WPA/WAPI Encryption tkip+aes
DHCP slots match the number of clients
Enabling the LAN side firewall made me lose internet connection so I don't want to mess things up anymore - I'm no network expert.
Interface grouping:
Group Name | WAN Interface | LAN Interfaces
Default | ppp0 | eth3
| | eth2
| | eth1
| | eth0
| | wlan0
LAN statistics show only eth0 and wl0 are transmitting/receiving data.
My operating system is Debian 6.0.7 (squeeze)