Which of the following options are parameters of EDCA? (Multiple choice)

Question

Options

• AAIFSN
• BSIFS
• CDIFS
• DTXOPLimit

• A
  85% (22)
• B
  12% (3)
• C
  4% (1)

Explanation

EDCA (Enhanced Distributed Channel Access), defined in IEEE 802.11e, uses per-Access-Category (AC) parameters to prioritize traffic. AIFSN (Arbitration Inter-Frame Space Number) is a core EDCA parameter - it defines how long each AC waits before contending, replacing the fixed DIFS of legacy DCF. TXOPLimit is also a key EDCA parameter, specifying the maximum duration a station may occupy the channel after winning contention, with higher-priority ACs getting larger TXOPs.

SIFS (B) is wrong because it's a fixed PHY-layer timing interval used for immediate responses like ACKs - it's not tunable per AC and has no role in EDCA's differentiation mechanism. DIFS (C) is wrong because it belongs to the legacy DCF (Distributed Coordination Function); EDCA specifically replaces DIFS with the flexible AIFS/AIFSN.

Memory tip: The four EDCA parameters per AC spell "ACT²" - AIFSN, CWmin, CWmax, TXOPLimit. If you see SIFS or DIFS as options, remember: DIFS = DCF, SIFS = fixed spacing - neither is an EDCA knob.

No community discussion yet for this question.