Comment at the top of ns-3.38/examples/wireless/wifi-aggregation.cc

// This is an example that illustrates how 802.11n aggregation is configured.
// It defines 4 independent Wi-Fi networks (working on different channels).
// Each network contains one access point and one station. Each station
// continuously transmits data packets to its respective AP.
//
// Network topology (numbers in parentheses are channel numbers):
//
//  Network A (36)   Network B (40)   Network C (44)   Network D (48)
//   *      *          *      *         *      *          *      *
//   |      |          |      |         |      |          |      |
//  AP A   STA A      AP B   STA B     AP C   STA C      AP D   STA D
//
// The aggregation parameters are configured differently on the 4 stations:
// - station A uses default aggregation parameter values (A-MSDU disabled, A-MPDU enabled with
// maximum size of 65 kB);
// - station B doesn't use aggregation (both A-MPDU and A-MSDU are disabled);
// - station C enables A-MSDU (with maximum size of 8 kB) but disables A-MPDU;
// - station D uses two-level aggregation (A-MPDU with maximum size of 32 kB and A-MSDU with maximum
// size of 4 kB).
//
// Packets in this simulation belong to BestEffort Access Class (AC_BE).
//
// The user can select the distance between the stations and the APs and can enable/disable the
// RTS/CTS mechanism. Example: ./ns3 run "wifi-aggregation --distance=10 --enableRts=0
// --simulationTime=20"
//
// The output prints the throughput measured for the 4 cases/networks described above. When default
// aggregation parameters are enabled, the maximum A-MPDU size is 65 kB and the throughput is
// maximal. When aggregation is disabled, the throughput is about the half of the physical bitrate.
// When only A-MSDU is enabled, the throughput is increased but is not maximal, since the maximum
// A-MSDU size is limited to 7935 bytes (whereas the maximum A-MPDU size is limited to 65535 bytes).
// When A-MSDU and A-MPDU are both enabled (= two-level aggregation), the throughput is slightly
// smaller than the first scenario since we set a smaller maximum A-MPDU size.
//
// When the distance is increased, the frame error rate gets higher, and the output shows how it
// affects the throughput for the 4 networks. Even through A-MSDU has less overheads than A-MPDU,
// A-MSDU is less robust against transmission errors than A-MPDU. When the distance is augmented,
// the throughput for the third scenario is more affected than the throughput obtained in other
// networks.