1
Q
What is a WISP in an WIFI hotspot?
A
A captive portal (may include auth server).
It is used before the routing to authenticate clients
2
Q
Why do we need authentication for WiFi hotstop and how can we realize it?
A
We need auth for privacy protection, billing purposes and legal reasons
We can use L2 (WPA), L3 (IPsec, PPTP) or L4 (captive portals)
3
Q
How can a client be redirected to a captive portal?
A
- ICMP redirect
- DNS spoofing
- Terminating TCP connections
- HTTP redirect
4
Q
How does eduroam handle authentication?
A
Via 802.1X and country-level RADIUS servers using user certificates and end-to-end tunneling
5
Q
Name some characteristics for train wifi networks
A
- Mulitple cellular interfaces
- Wifi for access in train stations
- Mobility is predefined by the train trcks
- 2-tier network access: mobile operator for WAN, backend service provider for train
