Dell PowerConnect 7048P User Manual - Page 513

What is the Internal Authentication Server? The Internal Authentication Server (IAS) is a dedicated database for local authentication of users for network access through 802.1X. In this database, the switch maintains a list of username and password combinations to use for 802.1X authentication. You can manually create entries in the database, or you can upload the IAS information to the switch. If the authentication method for 802.1X is IAS, the switch uses the locally stored list of username and passwords to provide port-based authentication to users instead of using an external authentication server. NOTE: The IAS database does not handle VLAN assignments or DiffServ policy assignments. What is Port Security? The Port Security feature allows you to limit the number of source MAC address that can be learned on a port. If a port reaches the configured limit, any other addresses beyond that limit are not learned and the frames are discarded. Frames with a source MAC address that has already been learned will be forwarded. The purpose of this feature, which is also known as port-MAC locking, is to help secure the network by preventing unknown devices from forwarding packets into the network. For example, to ensure that only a single device can be active on a port, you can set the number of allowable dynamic addresses to one. After the MAC address of the first device is learned, no other devices will be allowed to forward frames into the network. When link goes down on a port, all of the dynamically locked addresses are cleared from the source MAC address table the feature maintains. When the link is restored, that port can once again learn addresses up to the specified limit. The port can learn MAC addresses dynamically, and you can manually specify a list of static MAC addresses for a port. Configuring 802.1X and Port-Based Security 513