Shit I don’t remember and need to remember

Layers: Physical — digital bits as analog signals Data link — frames of digital bits over one link Network — packets of frames over multiple links Transport — end-to-end packet delivery Application — what the user needs

to compute hamming distance, xor the two bit strings and count the number of ones.

CDMA — code division multiple access, in physical layer with that chip sequence bullshit

CSMA — carrier sense multiple access, in mac protocol difference in CSMA types (MAC protocol)

• 1-persistent — always listens to channel, sends as soon as idle

• nonpersistent — senses channel, if not idle waits a random period of time and tries again. does not always listen.

• p-persistent — some probability fuckshit