ieee80211_llc_snap_header Struct Reference
[802.11 frame header formats]

The 802.2 LLC/SNAP header sent before actual data in a data frame. More...

#include <ieee80211.h>

Data Fields
u8	dsap
	Destination SAP ID.
u8	ssap
	Source SAP ID.
u8	ctrl
	Control information.
u8	oui [3]
	Organization code, usually 0.
u16	ethertype
	Ethernet Type field.

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Detailed Description

The 802.2 LLC/SNAP header sent before actual data in a data frame.

This header is not acknowledged in the 802.11 standard at all; it is treated just like data for MAC-layer purposes, including fragmentation and encryption. It is actually two headers concatenated: a three-byte 802.2 LLC header indicating Subnetwork Accesss Protocol (SNAP) in both source and destination Service Access Point (SAP) fields, and a five-byte SNAP header indicating a zero OUI and two-byte Ethernet protocol type field.

Thus, an eight-byte header in which six of the bytes are redundant. Lovely, isn't it?

Definition at line 323 of file ieee80211.h.

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Field Documentation

u8 ieee80211_llc_snap_header::dsap

Destination SAP ID.

Definition at line 326 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

u8 ieee80211_llc_snap_header::ssap

Source SAP ID.

Definition at line 327 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

u8 ieee80211_llc_snap_header::ctrl

Control information.

Definition at line 328 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

u8 ieee80211_llc_snap_header::oui[3]

Organization code, usually 0.

Definition at line 331 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

u16 ieee80211_llc_snap_header::ethertype

Ethernet Type field.

Definition at line 332 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

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The documentation for this struct was generated from the following file:

• include/gpxe/ieee80211.h