Introduction 25802.1ab (LLDP-MED)The Link Layer Discovery Protocol (LLDP) allows network managers to troubleshoot and enhancenetwork management by discovering and maintaining network topologies over multi-vendorenvironments. LLDP discovers network neighbors by standardizing methods for network devices toadvertise themselves to other systems, and to store discovered information. The multiple advertisementsets are sent in the packet Type Length Value (TLV) field. LLDP devices must support chassis and portID advertisement, as well as system name, system ID, system description, and system capabilityadvertisements.LLDP Media Endpoint Discovery (LLDP-MED) increases network flexibility by allowing differentIP systems to co-exist on a single network LLDP. It provides detailed network topology information,emergency call service via IP Phone location information, and troubleshooting information.Security FeaturesSSLSecure Socket Layer (SSL) is an application-level protocol that enables secure transactions of datathrough privacy, authentication, and data integrity. It relies upon certificates and public and private keys.Port Based Authentication (802.1x)Port based authentication enables authenticating system users on a per-port basis via an external server.Only authenticated and approved system users can transmit and receive data. Ports are authenticated viathe Remote Authentication Dial In User Service (RADIUS) server using the Extensible AuthenticationProtocol (EAP). Dynamic VLAN Assignment (DVA) allows network administrators to automaticallyassign users to VLANs during the RADIUS server authentication.For more information, see "Port Based Authentication."Locked Port SupportLocked Port increases network security by limiting access on a specific port only to users with specificMAC addresses. These addresses are either manually defined or learned on that port. When a frame isseen on a locked port, and the frame source MAC address is not tied to that port, the protectionmechanism is invoked.For more information, see "Configuring Port Security."RADIUS ClientRADIUS is a client/server-based protocol. A RADIUS server maintains a user database, which containsper-user authentication information, such as user name, password and accounting information.For more information, see "Configuring RADIUS Settings."
