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ns3::Bug555TestCase Class Reference
+ Inheritance diagram for ns3::Bug555TestCase:

Public Member Functions

virtual void DoRun (void)
 Implementation to actually run this test case. More...

Private Member Functions

void NotifyPhyTxBegin (Ptr< const Packet > p)
void SendOnePacket (Ptr< WifiNetDevice > dev)

Private Attributes

Time m_firstTransmissionTime
ObjectFactory m_mac
ObjectFactory m_manager
unsigned int m_numSentPackets
ObjectFactory m_propDelay
Time m_secondTransmissionTime

Additional Inherited Members

- Public Types inherited from ns3::TestCase
enum  TestDuration { QUICK = 1, EXTENSIVE = 2, TAKES_FOREVER = 3 }
 How long the test takes to execute. More...
- Protected Member Functions inherited from ns3::TestCase
 TestCase (std::string name)
void AddTestCase (TestCase *testCase) NS_DEPRECATED
 Add an individual test case to this test suite. More...
void AddTestCase (TestCase *testCase, enum TestDuration duration)
 Add an individual test case to this test suite. More...
std::string CreateDataDirFilename (std::string filename)
std::string CreateTempDirFilename (std::string filename)
bool GetErrorStatus (void) const NS_DEPRECATED
std::string GetName (void) const
bool IsStatusFailure (void) const
bool IsStatusSuccess (void) const
bool MustAssertOnFailure (void) const
bool MustContinueOnFailure (void) const
void ReportTestFailure (std::string cond, std::string actual, std::string limit, std::string message, std::string file, int32_t line)
void SetDataDir (std::string directory)

Detailed Description

Make sure that when multiple broadcast packets are queued on the same device in a short succession no virtual collision occurs

The observed behavior is that the first frame will be sent immediately, and the frames are spaced by (backoff + SIFS + AIFS) time intervals (where backoff is a random number of slot sizes up to maximum CW)

The following test case should not generate virtual collision for the second frame. The seed and run numbers were pick such that the second frame gets backoff = 0.

                 frame 1, frame 2
                 arrive                SIFS + AIFS
                 V                    <-----------> 

time |-----------—|----------------—|----------—|--------—> 0 1s 1.001408s 1.001442s ^ ^ ^ start TX finish TX start TX frame 1 frame 1 frame 2 ^ frame 2 backoff = 0

The buggy behavior was that frame 2 experiences a virtual collision and re-selects the backoff again. As a result, the actual backoff experience by frame 2 is less likely to be 0 since that would require two successions of 0 backoff (one that generates the virtual collision and one after the virtual collision).

Definition at line 317 of file wifi-test.cc.

Member Function Documentation

The documentation for this class was generated from the following file: