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4 limitations of wps – ZyXEL Communications NWD-270N User Manual

Page 26

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Chapter 2 Wireless LANs

NWD-270N User’s Guide

26

In step 3, you add another access point (AP2) to your network. AP2 is out of range of AP1, so
you cannot use AP1 for the WPS handshake with the new access point. However, you know
that Client 2 supports the registrar function, so you use it to perform the WPS handshake
instead.

Figure 9 WPS: Example Network Step 3

2.4.4 Limitations of WPS

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).

CLIENT 1

AP1

REGISTRAR

CLIENT 2

EXISTING CONNECTION

SEC

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Y IN

FO

ENROLLEE

AP1

EX

IST

ING

CO

NN

EC

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