Ethernet1QTag

Namespace inet

Ethernet1QTag

packet

Ethernet 802.1Q Tag.

Fields

Name Type Description
pcp uint8_t

Priority Code Point (PCP): a 3-bit field which refers to the IEEE 802.1p priority. It indicates the frame priority level. Values are from 0 (best effort) to 7 (highest); 1 represents the lowest priority.

de bool

Drop Eligible (DE): a 1-bit field. May be used separately or in conjunction with PCP to indicate frames eligible to be dropped in the presence of congestion.

VID short

VLAN Identifier (VID): a 12-bit field specifying the VLAN to which the frame belongs. The hexadecimal values of 0x000 and 0xFFF are reserved. All other values may be used as VLAN identifiers, allowing up to 4,094 VLANs. The reserved value 0x000 indicates that the frame does not belong to any VLAN; in this case, the 802.1Q tag specifies only a priority and is referred to as a priority tag. On bridges, VLAN 1 (the default VLAN ID) is often reserved for a management VLAN; this is vendor-specific.

Source code

//
// Ethernet 802.1Q Tag.
//
packet Ethernet1QTag
{
    uint8_t pcp;    // Priority Code Point (PCP): a 3-bit field which refers to the IEEE 802.1p priority. It indicates the frame priority level.
                    // Values are from 0 (best effort) to 7 (highest); 1 represents the lowest priority.
    bool de;        // Drop Eligible (DE): a 1-bit field. May be used separately or in conjunction with PCP to indicate frames eligible to be dropped in the presence of congestion.
    short VID = 0;   // VLAN Identifier (VID): a 12-bit field specifying the VLAN to which the frame belongs.
                    // The hexadecimal values of 0x000 and 0xFFF are reserved. All other values may be used as VLAN identifiers, allowing up to 4,094 VLANs.
                    // The reserved value 0x000 indicates that the frame does not belong to any VLAN; in this case,
                    // the 802.1Q tag specifies only a priority and is referred to as a priority tag. On bridges,
                    // VLAN 1 (the default VLAN ID) is often reserved for a management VLAN; this is vendor-specific.
}


File: src/inet/linklayer/ethernet/EtherFrame.msg