edsc(4) [debian man page]

EDSC(4) 						   BSD Kernel Interfaces Manual 						   EDSC(4)

NAME

     edsc -- Ethernet discard network interface

SYNOPSIS

     device edsc

DESCRIPTION

     The edsc interface is a software discard mechanism which may be used for performance analysis and software testing.  It imitates an Ethernet
     device, which allows for its use in conjunction with such drivers as if_bridge(4) and vlan(4).

     As with other network interfaces, an edsc interface must have network addresses assigned for each address family with which it is to be used.
     These addresses may be set or changed with the SIOCSIFADDR ioctl(2) or ifconfig(8) utility.

     Each edsc interface is created at runtime using interface cloning.  This is most easily done with the ifconfig(8) create command or using the
     cloned_interfaces variable in rc.conf(5).

SEE ALSO

     ioctl(2), arp(4), if_bridge(4), inet(4), intro(4), vlan(4), rc.conf(5), arp(8), ifconfig(8)

HISTORY

     The edsc device was derived from the disc(4) device and first appeared in FreeBSD 6.3.  This manpage was adapted from disc(4).

CAVEATS

     Since outgoing packets are just discarded by edsc, ARP requests stay unreplied.  Consequently, an IP packet cannot be sent via edsc until a
     static arp(4) entry is created for its next hop using arp(8).

     Initially an edsc interface has a zero link level address.  It can be changed with ifconfig(8) lladdr if needed.

BSD
								  March 25, 2007							       BSD

VLAN(4) 						   BSD Kernel Interfaces Manual 						   VLAN(4)

NAME

     vlan -- IEEE 802.1Q Virtual LAN network device

SYNOPSIS

     pseudo-device vlan

DESCRIPTION

     The vlan interface provides support for IEEE 802.1Q Virtual Local Area Networks (VLAN).  This supports the trunking of more than one network
     on a single network interface.  This is particularly useful on routers or on hosts which must be connected to many different networks through
     a single physical interface.

     To use a vlan interface, the administrator must first create the interface and then specify the VID (VLAN identifier, the first 12 bits from
     a 16-bit integer which distinguishes each VLAN from any others) and physical interface associated with the VLAN.  This can be done by using
     the ifconfig(8) create, vlan, and vlanif subcommands from a shell command line or script.	From within a C program, use the ioctl(2) system
     call with the SIOCSIFCREATE and SIOCSIFVLAN arguments.

     To be compatible with other IEEE 802.1Q devices, the vlan interface supports a 1500 byte MTU, which means that the parent interface will have
     to handle packets that are 4 bytes larger than the original Ethernet standard.  Drivers supporting this increased MTU are:

     -	 drivers using the DP8390 core (such as ec(4), ne(4), we(4), and possibly others)
     -	 bge(4)
     -	 bnx(4)
     -	 ea(4)
     -	 eb(4)
     -	 epic(4)
     -	 etherip(4)
     -	 ex(4)
     -	 fxp(4)
     -	 gem(4)
     -	 hme(4)
     -	 le(4)
     -	 sip(4)
     -	 ste(4)
     -	 stge(4)
     -	 ti(4)
     -	 tl(4)
     -	 tlp(4)
     -	 vge(4)
     -	 vr(4)
     -	 wm(4)
     -	 xi(4)

     vlan can be used with devices not supporting the IEEE 802.1Q MTU, but then the MTU of the vlan interface will be 4 bytes too small and will
     not interoperate properly with other IEEE 802.1Q devices, unless the MTU of the other hosts on the VLAN are also lowered to match.

EXAMPLES

     The following will create interface vlan0 with VID six, on the Ethernet interface tlp0:

	   ifconfig vlan0 create
	   ifconfig vlan0 vlan 6 vlanif tlp0

     After this set up, IP addresses (and/or other protocols) can be assigned to the vlan0 interface.  All other hosts on the Ethernet connected
     to tlp0 which configure a VLAN and use VID six will see all traffic transmitted through vlan0.

     The same VLAN can be created at system startup time by placing the following in /etc/ifconfig.vlan0:

	   create
	   vlan 6 vlanif tlp0

SEE ALSO

     ifconfig(8)

HISTORY

     The vlan device first appeared in NetBSD 1.5.1, and was derived from a VLAN implementation that appeared in FreeBSD and OpenBSD.

BUGS

     The vlan interfaces do not currently inherit changes made to the physical interfaces' MTU.

BSD
								 December 16, 2010							       BSD