ZyXEL Communications P-6600HW-Tx v3 User Manual

Chapter 9 Wireless LAN

P-660HW-Tx v3 User’s Guide

Figure 95   WPS: Example Network Step 3

WPS has some limitations of which you should be aware. 

• WPS works in Infrastructure networks only (where an AP and a wireless client 

communicate). It does not work in Ad-Hoc networks (where there is no AP).

• When you use WPS, it works between two devices only. You cannot enroll multiple 

devices simultaneously, you must enroll one after the other. 
For instance, if you have two enrollees and one registrar you must set up the first enrollee 
(by pressing the WPS button on the registrar and the first enrollee, for example), then 
check that it successfully enrolled, then set up the second device in the same way.

• WPS works only with other WPS-enabled devices. However, you can still add non-WPS 

devices to a network you already set up using WPS. 
WPS works by automatically issuing a randomly-generated WPA-PSK or WPA2-PSK 
pre-shared key from the registrar device to the enrollee devices. Whether the network uses 
WPA-PSK or WPA2-PSK depends on the device. You can check the configuration 
interface of the registrar device to discover the key the network is using (if the device 
supports this feature). Then, you can enter the key into the non-WPS device and join the 
network as normal (the non-WPS device must also support WPA-PSK or WPA2-PSK).

• When you use the PBC method, there is a short period (from the moment you press the 

button on one device to the moment you press the button on the other device) when any 
WPS-enabled device could join the network. This is because the registrar has no way of 
identifying the “correct” enrollee, and cannot differentiate between your enrollee and a 
rogue device. This is a possible way for a hacker to gain access to a network.