1fd558d18SJames Chapman# 2fd558d18SJames Chapman# Layer Two Tunneling Protocol (L2TP) 3fd558d18SJames Chapman# 4fd558d18SJames Chapman 5fd558d18SJames Chapmanmenuconfig L2TP 6fd558d18SJames Chapman tristate "Layer Two Tunneling Protocol (L2TP)" 7fd558d18SJames Chapman depends on INET 8fd558d18SJames Chapman ---help--- 9fd558d18SJames Chapman Layer Two Tunneling Protocol 10fd558d18SJames Chapman 11fd558d18SJames Chapman From RFC 2661 <http://www.ietf.org/rfc/rfc2661.txt>. 12fd558d18SJames Chapman 13fd558d18SJames Chapman L2TP facilitates the tunneling of packets across an 14fd558d18SJames Chapman intervening network in a way that is as transparent as 15fd558d18SJames Chapman possible to both end-users and applications. 16fd558d18SJames Chapman 17fd558d18SJames Chapman L2TP is often used to tunnel PPP traffic over IP 18fd558d18SJames Chapman tunnels. One IP tunnel may carry thousands of individual PPP 19fd558d18SJames Chapman connections. L2TP is also used as a VPN protocol, popular 20fd558d18SJames Chapman with home workers to connect to their offices. 21fd558d18SJames Chapman 22f7faffa3SJames Chapman L2TPv3 allows other protocols as well as PPP to be carried 23f7faffa3SJames Chapman over L2TP tunnels. L2TPv3 is defined in RFC 3931 24f7faffa3SJames Chapman <http://www.ietf.org/rfc/rfc3931.txt>. 25f7faffa3SJames Chapman 26fd558d18SJames Chapman The kernel component handles only L2TP data packets: a 27fd558d18SJames Chapman userland daemon handles L2TP the control protocol (tunnel 28fd558d18SJames Chapman and session setup). One such daemon is OpenL2TP 29fd558d18SJames Chapman (http://openl2tp.org/). 30fd558d18SJames Chapman 31fd558d18SJames Chapman If you don't need L2TP, say N. To compile all L2TP code as 32fd558d18SJames Chapman modules, choose M here. 33f7faffa3SJames Chapman 34*0ad66140SJames Chapmanconfig L2TP_DEBUGFS 35*0ad66140SJames Chapman tristate "L2TP debugfs support" 36*0ad66140SJames Chapman depends on L2TP && DEBUG_FS 37*0ad66140SJames Chapman help 38*0ad66140SJames Chapman Support for l2tp directory in debugfs filesystem. This may be 39*0ad66140SJames Chapman used to dump internal state of the l2tp drivers for problem 40*0ad66140SJames Chapman analysis. 41*0ad66140SJames Chapman 42*0ad66140SJames Chapman If unsure, say 'Y'. 43*0ad66140SJames Chapman 44*0ad66140SJames Chapman To compile this driver as a module, choose M here. The module 45*0ad66140SJames Chapman will be called l2tp_debugfs. 46*0ad66140SJames Chapman 47f7faffa3SJames Chapmanconfig L2TP_V3 48f7faffa3SJames Chapman bool "L2TPv3 support (EXPERIMENTAL)" 49f7faffa3SJames Chapman depends on EXPERIMENTAL && L2TP 50f7faffa3SJames Chapman help 51f7faffa3SJames Chapman Layer Two Tunneling Protocol Version 3 52f7faffa3SJames Chapman 53f7faffa3SJames Chapman From RFC 3931 <http://www.ietf.org/rfc/rfc3931.txt>. 54f7faffa3SJames Chapman 55f7faffa3SJames Chapman The Layer Two Tunneling Protocol (L2TP) provides a dynamic 56f7faffa3SJames Chapman mechanism for tunneling Layer 2 (L2) "circuits" across a 57f7faffa3SJames Chapman packet-oriented data network (e.g., over IP). L2TP, as 58f7faffa3SJames Chapman originally defined in RFC 2661, is a standard method for 59f7faffa3SJames Chapman tunneling Point-to-Point Protocol (PPP) [RFC1661] sessions. 60f7faffa3SJames Chapman L2TP has since been adopted for tunneling a number of other 61f7faffa3SJames Chapman L2 protocols, including ATM, Frame Relay, HDLC and even raw 62f7faffa3SJames Chapman ethernet frames. 63f7faffa3SJames Chapman 64f7faffa3SJames Chapman If you are connecting to L2TPv3 equipment, or you want to 65f7faffa3SJames Chapman tunnel raw ethernet frames using L2TP, say Y here. If 66f7faffa3SJames Chapman unsure, say N. 670d76751fSJames Chapman 680d76751fSJames Chapmanconfig L2TP_IP 690d76751fSJames Chapman tristate "L2TP IP encapsulation for L2TPv3" 700d76751fSJames Chapman depends on L2TP_V3 710d76751fSJames Chapman help 720d76751fSJames Chapman Support for L2TP-over-IP socket family. 730d76751fSJames Chapman 740d76751fSJames Chapman The L2TPv3 protocol defines two possible encapsulations for 750d76751fSJames Chapman L2TP frames, namely UDP and plain IP (without UDP). This 760d76751fSJames Chapman driver provides a new L2TPIP socket family with which 770d76751fSJames Chapman userspace L2TPv3 daemons may create L2TP/IP tunnel sockets 780d76751fSJames Chapman when UDP encapsulation is not required. When L2TP is carried 790d76751fSJames Chapman in IP packets, it used IP protocol number 115, so this port 800d76751fSJames Chapman must be enabled in firewalls. 810d76751fSJames Chapman 820d76751fSJames Chapman To compile this driver as a module, choose M here. The module 830d76751fSJames Chapman will be called l2tp_ip. 84d9e31d17SJames Chapman 85d9e31d17SJames Chapmanconfig L2TP_ETH 86d9e31d17SJames Chapman tristate "L2TP ethernet pseudowire support for L2TPv3" 87d9e31d17SJames Chapman depends on L2TP_V3 88d9e31d17SJames Chapman help 89d9e31d17SJames Chapman Support for carrying raw ethernet frames over L2TPv3. 90d9e31d17SJames Chapman 91d9e31d17SJames Chapman From RFC 4719 <http://www.ietf.org/rfc/rfc4719.txt>. 92d9e31d17SJames Chapman 93d9e31d17SJames Chapman The Layer 2 Tunneling Protocol, Version 3 (L2TPv3) can be 94d9e31d17SJames Chapman used as a control protocol and for data encapsulation to set 95d9e31d17SJames Chapman up Pseudowires for transporting layer 2 Packet Data Units 96d9e31d17SJames Chapman across an IP network [RFC3931]. 97d9e31d17SJames Chapman 98d9e31d17SJames Chapman This driver provides an ethernet virtual interface for each 99d9e31d17SJames Chapman L2TP ethernet pseudowire instance. Standard Linux tools may 100d9e31d17SJames Chapman be used to assign an IP address to the local virtual 101d9e31d17SJames Chapman interface, or add the interface to a bridge. 102d9e31d17SJames Chapman 103d9e31d17SJames Chapman If you are using L2TPv3, you will almost certainly want to 104d9e31d17SJames Chapman enable this option. 105d9e31d17SJames Chapman 106d9e31d17SJames Chapman To compile this driver as a module, choose M here. The module 107d9e31d17SJames Chapman will be called l2tp_eth. 108