BasicDSCPClassifier Class Reference

#include <BasicDSCPClassifier.h>

Inheritance diagram for BasicDSCPClassifier:

List of all members.

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Detailed Description

Just an example for packet classifiers, based on IPv4 DSCP/IPv6 Traffic class. You'll probably need to implement others if your research interest lies in QoS.

Public Member Functions
virtual int	numQueues ()
virtual int	classifyPacket (cMessage *msg)
Private Member Functions
virtual int	classifyByDSCP (int dscp)

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Member Function Documentation

int BasicDSCPClassifier::classifyByDSCP (  int  dscp  )  [private, virtual]

{ // DSCP is 6 bits, mask out all others dscp = (dscp & 0x3f); // DSCP format: // xxxxx0: used by standards; see RFC 2474 // xxxxx1: experimental or local use // source: Stallings, High-Speed Networks, 2nd Ed, p494 // all-zero DSCP maps to Best Effort (lowest priority) if (dscp==0) return BEST_EFFORT; // assume Best Effort service for experimental or local DSCP's too if (dscp & 1) return BEST_EFFORT; // from here on, we deal with non-zero standardized DSCP values only int upper3bits = (dscp & 0x3c) >> 3; //int lower3bits = (dscp & 0x07); -- we'll ignore this // rfc 2474, section 4.2.2: at least two independently forwarded classes of traffic have to be created if (upper3bits & 0x04) return 0; // highest priority else return 1; // low priority (best effort) }

int BasicDSCPClassifier::classifyPacket (  cMessage *  msg  )  [virtual]

The method should return the priority (the index of subqueue) for the given packet, a value between 0 and numQueues()-1 (inclusive). Implements IQoSClassifier. { if (dynamic_cast<IPDatagram *>(msg)) { // IPv4 QoS: map DSCP to queue number IPDatagram *datagram = (IPDatagram *)msg; int dscp = datagram->diffServCodePoint(); return classifyByDSCP(dscp); } #ifdef WITH_IPv6 else if (dynamic_cast<IPv6Datagram *>(msg)) { // IPv6 QoS: map Traffic Class to queue number IPv6Datagram *datagram = (IPv6Datagram *)msg; int dscp = datagram->trafficClass(); return classifyByDSCP(dscp); } #endif else { return BEST_EFFORT; // lowest priority ("best effort") } }

int BasicDSCPClassifier::numQueues (   )  [virtual]

Returns the largest value plus one classifyPacket() returns. Implements IQoSClassifier. { return 2; }

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

• BasicDSCPClassifier.h
• BasicDSCPClassifier.cc

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