Symbol Technologies Spectrum24 AP-4131 - Manual (Page 33)

Introduction
AP-4131 Access Point Product Reference Guide 23
The scanning and association process continues for active MUs.
This allows the MUs to find new APs and discard out-of-range or
deactivated APs. By testing the airwaves, the MUs can choose the best
network connection available.
The following diagram illustrates Mobile IP (roaming across routers):
Set the MU for Mobile IP as specified in the MU user documentation.
Security has become a concern to mobile users. Enabling the Mobile-Home
MD5 key option in the System Configuration menu generates a 16-byte
checksum authenticator using an MD5 algorithm. The MU and AP share the
checksum, called a key, to authenticate transmitted messages between them.
The AP and MU share the key while the MU is visiting a foreign subnet.
The MU and AP have to use the same key. If not, the AP refuses to become
the Home Agent for the MU. The maximum key length is 13 characters.
The AP allows all printable characters.