Layer 2 Tunneling Protocol

In computer networking, Layer 2 Tunneling Protocol (L2TP) is a tunneling protocol used to support virtual private networks (VPNs) or as part of the delivery of services by ISPs. It does not provide any encryption or confidentiality by itself; it relies on an encryption protocol that it passes within the tunnel to provide privacy.

Internet protocols
Application layer
  • DHCP
  • DHCPv6
  • DNS
  • FTP
  • HTTP
  • IMAP
  • IRC
  • LDAP
  • MGCP
  • NNTP
  • NTP
  • POP
  • RPC
  • RTP
  • RTSP
  • SIP
  • SMTP
  • SNMP
  • SOCKS
  • SSH
  • Telnet
  • TLS/SSL
  • XMPP
  • (more)
Transport layer
  • TCP
  • UDP
  • DCCP
  • SCTP
  • RSVP
  • (more)
Routing protocols *
  • BGP
  • OSPF
  • RIP
  • (more)
Internet layer
  • IP
    • IPv4
    • IPv6
  • ICMP
  • ICMPv6
  • ECN
  • IGMP
  • IPsec
  • (more)
Link layer
  • ARP/InARP
  • NDP
  • Tunnels
    • L2TP
  • PPP
  • Media access control
    • Ethernet
    • DSL
    • ISDN
    • FDDI
  • (more)
* Not a layer. A routing protocol belongs either to application or network layer.

Read more about Layer 2 Tunneling Protocol:  History, Description, Tunneling Models, L2TP Packet Structure, L2TP Packet Exchange, L2TP/IPsec, Windows Implementation, L2TP in ISPs' Networks

Famous quotes containing the words layer and/or tunneling:

    After a few months’ acquaintance with European “coffee,” one’s mind weakens, and his faith with it, and he begins to wonder if the rich beverage of home, with its clotted layer of yellow cream on top of it, is not a mere dream after all, and a thing which never existed.
    Mark Twain [Samuel Langhorne Clemens] (1835–1910)

    Our major universities are now stuck with an army of pedestrian, toadying careerists, Fifties types who wave around Sixties banners to conceal their record of ruthless, beaverlike tunneling to the top.
    Camille Paglia (b. 1947)