Collaboration diagram for Wifi Models:
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Models
The set of 802.11 models provided in ns-3 attempts to provide an accurate MAC-level implementation of the 802.11 specification and to provide a not-so-slow PHY-level model of the 802.11a specification.
The current implementation provides roughly 4 levels of models:
- the PHY layer models
- the so-called MAC low models: they implement DCF
- the so-called MAC high models: they implement the MAC-level beacon generation, probing, and association state machines.
- a set of Rate control algorithms used by the MAC low models.
We have today 3 MAC high models:
- a simple adhoc state machine which does not perform any kind of beacon generation, probing, or association. This state machine is implemented by the ns3::AdhocWifiNetDevice and ns3::MacHighAdhoc classes.
- an active probing and association state machine which handles automatic re-association whenever too many beacons are missed is implemented by the ns3::NqstaWifiNetDevice and ns3::MacHighNqsta classes.
- an access point which generates periodic beacons, and which accepts every attempt to associate. This AP state machine is implemented by the ns3::NqapWifiNetDevice and ns3::MacHighNqap classes.
The MAC low layer is split in 3 components:
- ns3::MacLow which takes care of RTS/CTS/DATA/ACK transactions.
- ns3::DcfManager and ns3::DcfState which implements the DCF function.
- ns3::DcaTxop which handles the packet queue, packet fragmentation, and packet retransmissions if they are needed.
The PHY layer implements a single model in the ns3::WifiPhy class: the physical layer model implemented there is described fully in a paper titled "Yet Another Network Simulator", available there: http://cutebugs.net/files/wns2-yans.pdf
It also provides a set of Rate control algorithms:
- ns3::ArfMacStations
- ns3::AArfMacStations
- ns3::IdealMacStations
- ns3::CrMacStations
- ns3::OnoeMacStations
- ns3::AmrrMacStations
