C++ definition

Implements the Ethernet CSMA/CD PHY protocol. It supports building both Ethernet CSMA/CD and Ethernet PLCA network interfaces.

This module detects the carrier signal and collisions on the channel. Frames are received correctly if there are no overlapping transmissions or receptions. It also supports sending special Ethernet signals: jam, commit, and beacon.

The upper layer must be connected to a module implementing the ~IEthernetCsmaMac C++ interface. There are two such modules: ~EthernetCsmaMac and ~EthernetPlca. The former can be used to build an Ethernet CSMA/CD network interface, the latter can be used to build an Ethernet PLCA network interface.

<b>See also:</b> ~EthernetCsmaPhy, ~EthernetPlca, ~EthernetPlcaInterface

Inheritance diagram

The following diagram shows inheritance relationships for this type. Unresolved types are missing from the diagram.

Used in compound modules

Name	Type	Description
EthernetPlcaInterface	compound module	Implements a network interface that is suitable for use in Ethernet 10BASE-T1S multidrop links. Such a multidrop link uses the Ethernet Phyisical Layer Collision Avoidance (PLCA) protocol. The protocol is defined in the IEEE 802.3cg-2019 standard. This network interface can be used in any network node module (e.g. ~StandardHost) that allows replacing its network interfaces. All network interfaces on the same multidrop link must use this module.

Extends

Name	Type	Description
SimpleModule	simple module	Base module for all INET simple modules.

Parameters

Name	Type	Default value	Description
displayStringTextFormat	string	""	Determines the text that is written on top of the submodule, supports displaying pars, watches, and module-specific information

Properties

Name	Value	Description
class	EthernetCsmaPhy
display	i=block/rxtx

Gates

Name	Direction	Size	Description
upperLayerIn	input
upperLayerOut	output
phys	inout

Signals

Name	Type	Unit	Description
receptionEnded	inet::physicallayer::EthernetSignalBase		emitted at the reception end, the value is the Ethernet signal being received
transmissionStarted	inet::physicallayer::EthernetSignalBase		emitted at the transmission start, the value is the Ethernet signal being transmitted
receptionStarted	inet::physicallayer::EthernetSignalBase		emitted at the reception start, the value is the Ethernet signal being received
receivedSignalType	int		emitted when the type of the received signal changes, the value is one of NONE, BEACON, COMMIT, DATA, JAM
busUsed	int		emitted when the bus usage changes, the value is 1 if DATA transmission or reception is in progress, 0 otherwise
stateChanged	int		emitted when the state of the state machine changes, the value is one of IDLE, TRANSMITTING, RECEIVING, COLLISION, CRS_ON
transmittedSignalType	int		emitted when the type of the transmitted signal changes, the value is one of NONE, BEACON, COMMIT, DATA, JAM
transmissionEnded	inet::physicallayer::EthernetSignalBase		emitted at the transmission end, the value is the Ethernet signal being transmitted

Statistics

Name	Title	Source	Record	Unit	Interpolation Mode	Description
transmissionTime	transmission time	packetDuration(transmissionEnded)	vector, histogram	s	none
receivedSignalType	received signal type		count, vector		sample-hold
transmitting	transmitting state	count(transmissionStarted) - count(transmissionEnded)	vector		sample-hold
propagationTime	propagation time			s
busUtilization	bus utilization	utilization(busUsed)	count, vector		linear	periodically calculated average bus usage, the value 1 means there was a DATA signal on the bus during the whole period, 0 means there was no DATA signal
state	state	stateChanged	count, vector		sample-hold	the time evolution of the state of the state machine
throughput	throughput	throughput(transmissionEnded)	vector, histogram	bps	linear
busUsed	bus used		count, vector		sample-hold	the time evolution of the bus used signal
transmittedSignalType	transmitted signal type		count, vector		sample-hold

Source code

//
// Implements the Ethernet CSMA/CD PHY protocol. It supports building
// both Ethernet CSMA/CD and Ethernet PLCA network interfaces.
//
// This module detects the carrier signal and collisions on the channel. Frames
// are received correctly if there are no overlapping transmissions or receptions.
// It also supports sending special Ethernet signals: jam, commit, and beacon.
//
// The upper layer must be connected to a module implementing the ~IEthernetCsmaMac
// C++ interface. There are two such modules: ~EthernetCsmaMac and ~EthernetPlca.
// The former can be used to build an Ethernet CSMA/CD network interface, the
// latter can be used to build an Ethernet PLCA network interface.
//
// @see ~EthernetCsmaPhy, ~EthernetPlca, ~EthernetPlcaInterface
//
simple EthernetCsmaPhy extends SimpleModule
{
    parameters:
        @class(EthernetCsmaPhy);
        // emitted when the state of the state machine changes, the value is one of IDLE, TRANSMITTING, RECEIVING, COLLISION, CRS_ON
        @signal[stateChanged](type=int);
        // emitted when the type of the received signal changes, the value is one of NONE, BEACON, COMMIT, DATA, JAM
        @signal[receivedSignalType](type=int);
        // emitted when the type of the transmitted signal changes, the value is one of NONE, BEACON, COMMIT, DATA, JAM
        @signal[transmittedSignalType](type=int);
        // emitted at the reception start, the value is the Ethernet signal being received
        @signal[receptionStarted](type=inet::physicallayer::EthernetSignalBase);
        // emitted at the reception end, the value is the Ethernet signal being received
        @signal[receptionEnded](type=inet::physicallayer::EthernetSignalBase);
        // emitted at the transmission start, the value is the Ethernet signal being transmitted
        @signal[transmissionStarted](type=inet::physicallayer::EthernetSignalBase);
        // emitted at the transmission end, the value is the Ethernet signal being transmitted
        @signal[transmissionEnded](type=inet::physicallayer::EthernetSignalBase);
        // emitted when the bus usage changes, the value is 1 if DATA transmission or reception is in progress, 0 otherwise
        @signal[busUsed](type=int);
        // the time evolution of the state of the state machine
        @statistic[state](title="state"; type=enum; enum=IDLE,TRANSMITTING,RECEIVING,COLLISION,CRS_ON; source=stateChanged; record=count,vector; interpolationmode=sample-hold);
        @statistic[receivedSignalType](title="received signal type"; type=enum; enum=NONE,BEACON,COMMIT,DATA,JAM; record=count,vector; interpolationmode=sample-hold);
        @statistic[transmittedSignalType](title="transmitted signal type"; type=enum; enum=NONE,BEACON,COMMIT,DATA,JAM; record=count,vector; interpolationmode=sample-hold);
        @statistic[transmitting](title="transmitting state"; type=int; source=count(transmissionStarted) - count(transmissionEnded); record=vector; interpolationmode=sample-hold);
        @statistic[throughput](title="throughput"; unit=bps; source=throughput(transmissionEnded); record=vector,histogram; interpolationmode=linear);
        @statistic[propagationTime](title="propagation time"; unit=s);
        @statistic[transmissionTime](title="transmission time"; unit=s; source=packetDuration(transmissionEnded); record=vector,histogram; interpolationmode=none);
        // the time evolution of the bus used signal
        @statistic[busUsed](title="bus used"; record=count,vector; interpolationmode=sample-hold);
        // periodically calculated average bus usage, the value 1 means there was a DATA signal on the bus during the whole period, 0 means there was no DATA signal
        @statistic[busUtilization](title="bus utilization"; source=utilization(busUsed); record=count,vector; interpolationmode=linear);
        @display("i=block/rxtx");
    gates:
        input upperLayerIn @labels(EtherFrame);
        output upperLayerOut @labels(EtherFrame);
        inout phys @labels(EthernetSignal);
}

File: src/inet/physicallayer/wired/ethernet/EthernetCsmaPhy.ned

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