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4 .\" This software was developed by CK Software GmbH under sponsorship
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35 .Nd A pair of virtual back-to-back connected Ethernet interfaces
37 To compile this driver into the kernel,
38 place the following line in your
39 kernel configuration file:
40 .Bd -ragged -offset indent
44 Alternatively, to load the driver as a
45 module at boot time, place the following line in
47 .Bd -literal -offset indent
53 is a pair of Ethernet-like software interfaces,
54 which are connected back-to-back with a virtual cross-over cable.
58 interface pair is created at runtime using interface cloning.
59 This is most easily done with the
66 While for cloning you only give either
72 pair will be named like
74 This means the names of the first
81 Like any other Ethernet interface, an
83 needs to have a network address.
86 will be assigned a locally administered address by default,
87 that is only guaranteed to be unique within one network stack.
88 To change the default addresses one may use the SIOCSIFADDR ioctl(2) or
91 The basic intent is to provide connectivity between two virtual
92 network stack instances.
95 one end of the interface pair can also be part of another (virtual) LAN.
96 As with any other Ethernet interface,
100 configured on top of it.
113 interface first appeared in
118 interface was written by
119 .An Bjoern A. Zeeb, CK Software GmbH,
120 under sponsorship from the FreeBSD Foundation.