1 .\" Copyright (c) Andrey V. Elsukov <ae@FreeBSD.org>
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32 .Nd encapsulating network device
35 driver into the kernel, place the following line in the kernel
37 .Bd -ragged -offset indent
41 Alternatively, to load the
42 driver as a module at boot time, place the following line in
44 .Bd -literal -offset indent
50 network interface pseudo device encapsulates datagrams
52 These encapsulated datagrams are routed to a destination host,
53 where they are decapsulated and further routed to their final destination.
56 interfaces are dynamically created and destroyed with the
63 This driver corresponds to RFC 2004.
64 Datagrams are encapsulated into IP with a shorter encapsulation.
66 IP header is modified and the modifications are inserted between the
67 so modified header and the original payload.
68 The protocol number 55 is used for outer header.
70 For correct operation, the
72 device needs a route to the decapsulating host that does not run over the tunnel,
73 as this would be a loop.
84 .An Andrey V. Elsukov Aq Mt ae@FreeBSD.org