[Ns-developers] 6 MAC addresses in 802.11 frames?

[Salvo Danilo Giuffrida]

Hello,
I looked into the definition of struct hdr_mac802_11, which represents
802.11 MAC headers. I saw that, among others, the definition of these
4 variables:
	u_char                  dh_ra[ETHER_ADDR_LEN];
        u_char                  dh_ta[ETHER_ADDR_LEN];
        u_char                  dh_3a[ETHER_ADDR_LEN];
	u_char			dh_4a[ETHER_ADDR_LEN];

Are these, respectively
1 - The receiver's address (next hop)
2 - The transmitter's address
3 - The source address
4 - The destination address
?
If yes, then why there are also in the struct hdr_mac (mac.h) the
following two variables?
	int macSA_;		// source MAC address
	int macDA_;		// destination MAC address

If an 802.11 frame contains also the common MAC header, doesn't this
mean that it has 6 addresses (4 u_char arrays from hdr_mac802_11, and
2 integers from hdr_mac)? And, why are they declared in hdr_mac
declared integers, while in hdr_mac802_11 as u_char arrays?
Thanks a lot