This chapter deals with topics crucial to WLAN security that deserve special attention. Each has a useful and unique approach to WLAN security and merits coverage in this text. The subjects in this chapter are unrelated to each other, or to other categories, which is why they are covered as "additional" security solutions. Included herein are discussions about intrusion detection systems, thin client network models, using DHCP for authentication, network traffic baselining, Kerberos, RADIUS, LDAP, and some emerging standards; each of these technologies offers additional layers of security to WLANs