Description

A transmission channel model that supports propagation delay, transmission duration computed from a data rate or given explicitly, and a simple error model with based on bit error rate (BER) and packet error rate (PER). The above parameters can be supplied via NED or explicit setter methods.

This class is a transmission channel, i.e. its isTransmissionChannel() method returns true. There can be at most one transmission channel in a connection path.

The treatment of packets depends on the mode setting. In mode=SINGLE, at most one transmission can be active at any given time, and overlapping transmissions are not permitted. In mode=MULTI, multiple concurrent transmissions are allowed, with consistency checking (transmission updates must refer to existing and active transmissions). The UNCHECKED mode is the low-overhead version of MULTI: the channel does not keep track of ongoing transmissions, so there are no consistency checks, and certain functionality is unavailable (e.g. the channel does not emit channelBusy signals).

Non-packet messages are let through at any time, after applying propagation delay only. They do not interfere with ongoing transmissions in any way.

By default, transmission duration is computed from the packet bit length and the channel datarate. The channel datarate is optional; if it is missing, the packet duration needs to be specified explicitly in the send() call (see SendOptions). If both datarate and explicit duration are present, the explicit duration takes precedence.

Allowing to override the duration is useful for a few cases: to account for certain parts in the frame (preamble, padding, PHY-layer header with different datarate, etc.) and for aborting at arbitrary time (for example at a fractional bit time).

The channel supports updating the ongoing transmission (see SendOptions). Duration and remainingDuration are optional, as long as the missing one(s) can be computed from the others. For example, duration can be computed as the elapsed transmission time plus remainingDuration (unless in UNCHECKED mode, when the channel doesn't keep the needed information around). Sanity checks (e.g. duration/remainingDuration cannot be negative, duration >= remainingDuration, etc.) are included.

Inheritance diagram for cDatarateChannel:

[legend]

Public Types
enum	Mode { SINGLE, MULTI, UNCHECKED }

Public Member Functions
Redefined cObject member functions.
virtual std::string	str () const override

Setting and getting channel parameters.
virtual bool	isTransmissionChannel () const override

virtual void	setMode (Mode mode)

virtual void	setDelay (double d)

virtual void	setDatarate (double d)

virtual void	setBitErrorRate (double d)

virtual void	setPacketErrorRate (double d)

virtual void	setDisabled (bool d)

virtual Mode	getMode () const

virtual simtime_t	getDelay () const

virtual double	getDatarate () const

virtual double	getBitErrorRate () const

virtual double	getPacketErrorRate () const

virtual bool	isDisabled () const override

Transmission state.
virtual double	getNominalDatarate () const override

virtual simtime_t	calculateDuration (cMessage *msg) const override

virtual simtime_t	getTransmissionFinishTime () const override

virtual bool	isBusy () const override

virtual void	forceTransmissionFinishTime (simtime_t t) override

Implementation methods
virtual void	initialize () override

virtual Result	processMessage (cMessage *msg, const SendOptions &options, simtime_t t) override

Public Member Functions inherited from cChannel
virtual void	finalizeParameters () override

	cChannel (const char *name=nullptr)

virtual	~cChannel ()

virtual void	callInitialize () override

virtual bool	callInitialize (int stage) override

virtual void	callFinish () override

virtual ComponentKind	getComponentKind () const override

virtual cModule *	getParentModule () const override

cChannelType *	getChannelType () const

virtual cProperties *	getProperties () const override

virtual cGate *	getSourceGate () const

Public Member Functions inherited from cComponent
	cComponent (const char *name=nullptr)

virtual	~cComponent ()

virtual void	forEachChild (cVisitor *v) override

const cComponent *	getThisPtr () const

virtual void	setDisplayName (const char *name)

virtual const char *	getDisplayName () const

virtual cComponentType *	getComponentType () const

cSimulation *	getSimulation () const

int	getId () const

virtual const char *	getNedTypeName () const

virtual std::string	getNedTypeAndFullName () const

virtual std::string	getNedTypeAndFullPath () const

bool	isModule () const

bool	isChannel () const

virtual cModule *	getSystemModule () const

virtual cModule *	getModuleByPath (const char *path) const

virtual cModule *	findModuleByPath (const char *path) const

virtual int	getNumParams () const

virtual cPar &	par (int k)

const cPar &	par (int k) const

virtual cPar &	par (const char *parname)

const cPar &	par (const char *parname) const

virtual int	findPar (const char *parname) const

bool	hasPar (const char *s) const

virtual cRNG *	getRNG (int k) const

virtual uint32_t	intrand (uint32_t r, int rng=0) const

virtual double	dblrand (int rng=0) const

virtual double	uniform (double a, double b, int rng=0) const

virtual SimTime	uniform (SimTime a, SimTime b, int rng=0) const

virtual double	exponential (double mean, int rng=0) const

virtual SimTime	exponential (SimTime mean, int rng=0) const

virtual double	normal (double mean, double stddev, int rng=0) const

virtual SimTime	normal (SimTime mean, SimTime stddev, int rng=0) const

virtual double	truncnormal (double mean, double stddev, int rng=0) const

virtual SimTime	truncnormal (SimTime mean, SimTime stddev, int rng=0) const

virtual double	gamma_d (double alpha, double theta, int rng=0) const

virtual double	beta (double alpha1, double alpha2, int rng=0) const

virtual double	erlang_k (unsigned int k, double mean, int rng=0) const

virtual double	chi_square (unsigned int k, int rng=0) const

virtual double	student_t (unsigned int i, int rng=0) const

virtual double	cauchy (double a, double b, int rng=0) const

virtual double	triang (double a, double b, double c, int rng=0) const

virtual double	lognormal (double m, double w, int rng=0) const

virtual double	weibull (double a, double b, int rng=0) const

virtual double	pareto_shifted (double a, double b, double c, int rng=0) const

virtual int	intuniform (int a, int b, int rng=0) const

virtual int	intuniformexcl (int a, int b, int rng=0) const

virtual int	bernoulli (double p, int rng=0) const

virtual int	binomial (int n, double p, int rng=0) const

virtual int	geometric (double p, int rng=0) const

virtual int	negbinomial (int n, double p, int rng=0) const

virtual int	poisson (double lambda, int rng=0) const

virtual void	subscribe (simsignal_t signalID, cIListener *listener)

virtual void	subscribe (const char signalName, cIListener listener)

virtual void	unsubscribe (simsignal_t signalID, cIListener *listener)

virtual void	unsubscribe (const char signalName, cIListener listener)

virtual bool	isSubscribed (simsignal_t signalID, cIListener *listener) const

virtual bool	isSubscribed (const char signalName, cIListener listener) const

virtual std::vector< simsignal_t >	getLocalListenedSignals () const

virtual std::vector< cIListener * >	getLocalSignalListeners (simsignal_t signalID) const

virtual bool	hasGUI () const

virtual cDisplayString &	getDisplayString () const

virtual void	setDisplayString (const char *dispstr)

virtual void	bubble (const char *text) const

virtual std::string	resolveResourcePath (const char *fileName) const

virtual void	recordScalar (const char name, double value, const char unit=nullptr)

virtual void	recordScalar (const char name, SimTime value, const char unit=nullptr)

virtual void	recordStatistic (cStatistic stats, const char unit=nullptr)

virtual void	recordStatistic (const char name, cStatistic stats, const char *unit=nullptr)

virtual void	emit (simsignal_t signalID, bool b, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, double d, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, const SimTime &t, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, const char s, cObject details=nullptr)

virtual void	emit (simsignal_t signalID, cObject obj, cObject details=nullptr)

virtual void	emit (simsignal_t signalID, const cObject obj, cObject details=nullptr)

virtual void	emit (simsignal_t signalID, char c, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, unsigned char c, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, short i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, unsigned short i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, int i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, unsigned int i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, long i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, unsigned long i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, long long i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, unsigned long long i, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, float f, cObject *details=nullptr)

virtual void	emit (simsignal_t signalID, long double d, cObject *details=nullptr)

bool	mayHaveListeners (simsignal_t signalID) const

bool	hasListeners (simsignal_t signalID) const

Public Member Functions inherited from cSoftOwner
	cSoftOwner (const char *name=nullptr, bool namepooling=true)

virtual	~cSoftOwner ()

virtual bool	isSoftOwner () const override

int	getNumOwnedObjects () const

cOwnedObject *	getOwnedObject (int k)

Public Member Functions inherited from cNoncopyableOwnedObject
	cNoncopyableOwnedObject (const char *name=nullptr, bool namepooling=true)

virtual cNoncopyableOwnedObject *	dup () const override

Public Member Functions inherited from cOwnedObject
	cOwnedObject ()

	cOwnedObject (const char *name, bool namepooling=true)

	cOwnedObject (const cOwnedObject &obj)

virtual	~cOwnedObject ()

cOwnedObject &	operator= (const cOwnedObject &o)

virtual cObject *	getOwner () const override

virtual bool	isOwnedObject () const override

Public Member Functions inherited from cNamedObject
	cNamedObject ()

	cNamedObject (const char *name, bool namepooling=true)

	cNamedObject (const cNamedObject &obj)

virtual	~cNamedObject ()

cNamedObject &	operator= (const cNamedObject &o)

virtual void	setName (const char *s)

virtual const char *	getName () const override

virtual void	setNamePooling (bool b)

virtual bool	getNamePooling ()

Public Member Functions inherited from cObject
	cObject ()

	cObject (const cObject &other)=default

virtual	~cObject ()

virtual const char *	getClassName () const

bool	isName (const char *s) const

virtual const char *	getFullName () const

virtual std::string	getFullPath () const

virtual std::string	getClassAndFullName () const

virtual std::string	getClassAndFullPath () const

const cObject *	getThisPtr () const

virtual std::ostream &	printOn (std::ostream &os) const

cObject *	findObject (const char *name, bool deep=true)

virtual cClassDescriptor *	getDescriptor () const

void	copyNotSupported () const

Protected Member Functions
virtual void	handleParameterChange (const char *parname) override

virtual void	finish () override

Protected Member Functions inherited from cComponent
virtual void	initialize (int stage)

virtual int	numInitStages () const

virtual void	refreshDisplay () const

virtual void	preDelete (cComponent *root)

Protected Member Functions inherited from cSoftOwner
virtual void	take (cOwnedObject *obj) override

virtual void	drop (cOwnedObject *obj) override

Protected Member Functions inherited from cObject
void	dropAndDelete (cOwnedObject *obj)

Constructors, destructor
	cDatarateChannel (const char *name=nullptr)

virtual	~cDatarateChannel ()

static cDatarateChannel *	create (const char *name)

Additional Inherited Members
Static Public Member Functions inherited from cComponent
static simsignal_t	registerSignal (const char *name)

static const char *	getSignalName (simsignal_t signalID)

Static Public Member Functions inherited from cOwnedObject
static long	getTotalObjectCount ()

static long	getLiveObjectCount ()

static void	resetObjectCounters ()

static cSoftOwner *	getOwningContext ()

Member Enumeration Documentation

◆ Mode

enum Mode

Channel operating mode

Enumerator
SINGLE	Allow a single transmission at a time.
MULTI	Allow multiple concurrent transmissions, with consistency checks.
UNCHECKED	Allow multiple concurrent transmissions, with low overhead. In this mode, the channel does not keep track of ongoing transmissions, so there are no consistency checks, the isBusy() and getTransmissionFinishTime() methods are not supported, and the channel does not emit channelBusy signals.

Constructor & Destructor Documentation

◆ cDatarateChannel()

cDatarateChannel ( const char * name = nullptr )

explicit

Constructor. This is only for internal purposes, and should not be used when creating channels dynamically; use the create() factory method instead.

◆ ~cDatarateChannel()

virtual ~cDatarateChannel ( )

inlinevirtual

Destructor.

Member Function Documentation

◆ handleParameterChange()

virtual void handleParameterChange ( const char * parname )

overrideprotectedvirtual

This method is called by the simulation kernel to notify the module or channel that the value of an existing parameter has changed. Redefining this method allows simple modules and channels to be react on parameter changes, for example by re-reading the value. This default implementation does nothing.

Notification is initially disabled until all parameters have been set up, that is, until finalizeParameters() is invoked on this component. However, notifications are enabled while the component goes through (single or multi-stage) initialization. When implementing handleParameterChange(), one must keep in mind that the component may not have been fully initialized at the time of the call (e.g. may not have gone through all init stages yet).

One must be extremely careful when changing parameters from inside handleParameterChange(), to avoid creating infinite notification loops.

Note: before OMNeT++ version 6.0, handleParameterChange() was disabled during the whole initialization process, and handleParameterChange(nullptr) was called after the last stage of the initialization. This is no longer so in version 6.0 or later.

Reimplemented from cComponent.

◆ finish()

virtual void finish ( )

overrideprotectedvirtual

Finish hook. finish() is called after end of simulation if it terminated without error. This default implementation does nothing.

Reimplemented from cComponent.

◆ create()

static cDatarateChannel* create ( const char * name )

static

Utility function for dynamic channel creation. Equivalent to cChannelType::getDatarateChannelType()->create(name).

◆ str()

virtual std::string str ( ) const

overridevirtual

Produces a one-line description of the object's contents. See cObject for more details.

Reimplemented from cChannel.

◆ isTransmissionChannel()

virtual bool isTransmissionChannel ( ) const

inlineoverridevirtual

Returns true.

Implements cChannel.

◆ setMode()

virtual void setMode ( Mode mode )

virtual

Sets the operating mode. Switching operating mode during simulation (when the channel is in use) is not allowed.

◆ setDelay()

virtual void setDelay ( double d )

virtual

Sets the propagation delay of the channel, in seconds.

◆ setDatarate()

virtual void setDatarate ( double d )

virtual

Sets the data rate of the channel, in bit/second.

See also: isBusy(), getTransmissionFinishTime()

◆ setBitErrorRate()

virtual void setBitErrorRate ( double d )

virtual

Sets the bit error rate (BER) of the channel.

See also: cPacket::hasBitError()

◆ setPacketErrorRate()

virtual void setPacketErrorRate ( double d )

virtual

Sets the packet error rate (PER) of the channel.

See also: cPacket::hasBitError()

◆ setDisabled()

virtual void setDisabled ( bool d )

virtual

Disables or enables the channel.

◆ getMode()

virtual Mode getMode ( ) const

inlinevirtual

Returns the operating mode.

◆ getDelay()

virtual simtime_t getDelay ( ) const

inlinevirtual

Returns the propagation delay of the channel, in seconds. This method is equivalent to reading the "delay" parameter, via par("delay").

◆ getDatarate()

virtual double getDatarate ( ) const

inlinevirtual

Returns the data rate of the channel, in bit/second. This method is equivalent to reading the "datarate" parameter, via par("datarate"). This value affects the transmission time of messages sent through the channel.

◆ getBitErrorRate()

virtual double getBitErrorRate ( ) const

inlinevirtual

Returns the bit error rate (BER) of the channel. This method is equivalent to reading the "ber" parameter, via par("ber"). When a message sent through the channel suffers at least one bit error, its bit error flag will be set.

◆ getPacketErrorRate()

virtual double getPacketErrorRate ( ) const

inlinevirtual

Returns the packet error rate (PER) of the channel. This method is equivalent to reading the "per" parameter, via par("per"). When a message is sent through the channel, its bit error flag will be set with this probability.

◆ isDisabled()

virtual bool isDisabled ( ) const

inlineoverridevirtual

Returns whether the channel is disabled. This method is equivalent to reading the "disabled" parameter, via par("disabled"). A disabled channel discards all messages sent on it.

Reimplemented from cChannel.

◆ getNominalDatarate()

virtual double getNominalDatarate ( ) const

inlineoverridevirtual

Same as getDatarate().

Implements cChannel.

◆ calculateDuration()

virtual simtime_t calculateDuration ( cMessage * msg ) const

overridevirtual

Returns the message length in bits divided by the datarate.

Note that processMessage() does NOT call this method, so in order to change the duration computation algorithm via subclassing you need to redefine both this and processMessage().

Implements cChannel.

◆ getTransmissionFinishTime()

virtual simtime_t getTransmissionFinishTime ( ) const

overridevirtual

Returns the simulation time all transmissions will finish on the (sender side) of the channel. If there is no ongoing transmission, the result is undefined but less or equal the current simulation time.

This method is unsupported (throws exception) in the UNCHECKED mode.

Implements cChannel.

◆ isBusy()

virtual bool isBusy ( ) const

overridevirtual

Returns whether the sender gate is currently transmitting, ie. whether transmissionFinishTime() is greater than the current simulation time.

This method is unsupported (throws exception) in the UNCHECKED mode.

Reimplemented from cChannel.

◆ forceTransmissionFinishTime()

virtual void forceTransmissionFinishTime ( simtime_t t )

overridevirtual

DEPRECATED METHOD. It is only provided for backward compatibility with OMNeT++ 5.x.

This method forcibly overwrites the finish time of the current transmission in the channel. It is a crude device that allows implementing aborting transmissions. Models using this method should be migrated to the transmission update API.

See also: cSimpleModule::SendOptions, getTransmissionFinishTime(), isBusy()

Reimplemented from cChannel.

◆ initialize()

virtual void initialize ( )

overridevirtual

Initialization.

Reimplemented from cComponent.

◆ processMessage()

virtual Result processMessage	(	cMessage *	msg,
		const SendOptions &	options,
		simtime_t	t
	)

overridevirtual

Performs bit error rate, delay and transmission time modelling.

Implements cChannel.

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

cdataratechannel.h

	OMNeT++ API 6.1 Discrete Event Simulation Library

Description

Public Types

Public Member Functions

Protected Member Functions

Constructors, destructor

Additional Inherited Members

Member Enumeration Documentation

◆ Mode

Constructor & Destructor Documentation

◆ cDatarateChannel()

◆ ~cDatarateChannel()

Member Function Documentation

◆ handleParameterChange()

◆ finish()

◆ create()

◆ str()

◆ isTransmissionChannel()

◆ setMode()

◆ setDelay()

◆ setDatarate()

◆ setBitErrorRate()

◆ setPacketErrorRate()

◆ setDisabled()

◆ getMode()

◆ getDelay()

◆ getDatarate()

◆ getBitErrorRate()

◆ getPacketErrorRate()

◆ isDisabled()

◆ getNominalDatarate()

◆ calculateDuration()

◆ getTransmissionFinishTime()

◆ isBusy()

◆ forceTransmissionFinishTime()

◆ initialize()

◆ processMessage()