1# 2# Layer Two Tunneling Protocol (L2TP) 3# 4 5menuconfig L2TP 6 tristate "Layer Two Tunneling Protocol (L2TP)" 7 depends on INET 8 ---help--- 9 Layer Two Tunneling Protocol 10 11 From RFC 2661 <http://www.ietf.org/rfc/rfc2661.txt>. 12 13 L2TP facilitates the tunneling of packets across an 14 intervening network in a way that is as transparent as 15 possible to both end-users and applications. 16 17 L2TP is often used to tunnel PPP traffic over IP 18 tunnels. One IP tunnel may carry thousands of individual PPP 19 connections. L2TP is also used as a VPN protocol, popular 20 with home workers to connect to their offices. 21 22 L2TPv3 allows other protocols as well as PPP to be carried 23 over L2TP tunnels. L2TPv3 is defined in RFC 3931 24 <http://www.ietf.org/rfc/rfc3931.txt>. 25 26 The kernel component handles only L2TP data packets: a 27 userland daemon handles L2TP the control protocol (tunnel 28 and session setup). One such daemon is OpenL2TP 29 (http://openl2tp.org/). 30 31 If you don't need L2TP, say N. To compile all L2TP code as 32 modules, choose M here. 33 34config L2TP_V3 35 bool "L2TPv3 support (EXPERIMENTAL)" 36 depends on EXPERIMENTAL && L2TP 37 help 38 Layer Two Tunneling Protocol Version 3 39 40 From RFC 3931 <http://www.ietf.org/rfc/rfc3931.txt>. 41 42 The Layer Two Tunneling Protocol (L2TP) provides a dynamic 43 mechanism for tunneling Layer 2 (L2) "circuits" across a 44 packet-oriented data network (e.g., over IP). L2TP, as 45 originally defined in RFC 2661, is a standard method for 46 tunneling Point-to-Point Protocol (PPP) [RFC1661] sessions. 47 L2TP has since been adopted for tunneling a number of other 48 L2 protocols, including ATM, Frame Relay, HDLC and even raw 49 ethernet frames. 50 51 If you are connecting to L2TPv3 equipment, or you want to 52 tunnel raw ethernet frames using L2TP, say Y here. If 53 unsure, say N. 54 55config L2TP_IP 56 tristate "L2TP IP encapsulation for L2TPv3" 57 depends on L2TP_V3 58 help 59 Support for L2TP-over-IP socket family. 60 61 The L2TPv3 protocol defines two possible encapsulations for 62 L2TP frames, namely UDP and plain IP (without UDP). This 63 driver provides a new L2TPIP socket family with which 64 userspace L2TPv3 daemons may create L2TP/IP tunnel sockets 65 when UDP encapsulation is not required. When L2TP is carried 66 in IP packets, it used IP protocol number 115, so this port 67 must be enabled in firewalls. 68 69 To compile this driver as a module, choose M here. The module 70 will be called l2tp_ip. 71