user manual

Glossary
GL-20
Cisco Router and Security Device Manager 2.5 User’s Guide
OL-4015-12
key exchange
The method by which two or more parties exchange encryption keys. The IKE
protocol provides one such method.
key lifetime
An attribute of a key pair that specifies a time span, during which the certificate
containing the public component of that key pair is considered valid.
key management
The creation, distribution, authentication, and storage of encryption keys.
key pair
See public key encryption.
key recovery
A trusted method by which encrypted information can be decrypted if the
decryption key is lost or destroyed.
L
L2F Protocol
Layer 2 Forwarding Protocol. Protocol that supports the creation of secure
virtual private dial-up networks over the Internet.
L2TP
Layer 2 Tunneling Protocol. An Internet Engineering Task Force (IETF)
standards track protocol defined in RFC 2661 that provides tunneling of PPP.
Based upon the best features of L2F and PPTP, L2TP provides an industry-wide
interoperable method of implementing VPDN. L2TP is proposed as an IPSec
alternative, but is used sometimes alongside IPSec to provide authentication
services.
LAC
L2TP access concentrator. Device terminating calls to remote systems and
tunneling PPP sessions between remote systems and the LNS.
LAN
Local Area Network. A network residing in one location or belonging to one
organization, typically, but not necessarily using IP and other Internet protocols.
Not the global Internet. See also intranet, network, Internet.
LAPB
Link Access Procedure, Balanced.
Layer 3 Interface
Layer 3 interfaces support internetwork routing. A VLAN is an example of a
logical layer 3 interface. An Ethernet port is an example of a physical layer 3
interface.
LBO
Line Build Out.