Ieee802154NarrowbandMac

Package: inet.linklayer.ieee802154

Ieee802154NarrowbandMac

compound module

(no description)

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
Ieee802154NarrowbandInterface compound module

This module implements an IEEE 802.15.4 narrowband network interface.

Extends

Name Type Description
Ieee802154Mac compound module

Generic CSMA protocol supporting Mac-ACKs as well as constant, linear or exponential backoff times.

Parameters

Name Type Default value Description
interfaceTableModule string
address string "auto"

MAC address as hex string (12 hex digits), or "auto". "auto" values will be replaced by a generated MAC address in init stage 0.

headerLength int 72 b

length of MAC header

mtu int 127 Byte - 9 Byte
bitrate double 250000 bps

bit rate

ccaDetectionTime double 0.000128 s

Clear Channel Assessment detection time

rxSetupTime double 0s

Time to setup radio to reception state

aTurnaroundTime double 0.000192 s

Time to switch radio from Rx to Tx state

useMACAcks bool true

Send/Expect MAC acks for unicast traffic?

macMaxFrameRetries int 3

Maximum number of frame retransmission, only used when usage of MAC acks is enabled.

macAckWaitDuration double 0.00056 s

Time to wait for an acknowledgement after transmitting a unicast frame. Only used when usage of MAC acks is enabled. Value is calculated from 1+12+10+12 symbols, which is defined for nonbeacon-enabled PAN. In the non-beacon-enabled case, the receiver responds at aTurnaroundTime (i.e. the time for the sender and receiver to both be guaranteed to have switched from Tx to Rx and vice verse). This gives the value 192us + 352us = 544us (there's been some discussion about the "extra" 1 symbol == 16us) [section 7.5.6.4.2 of the specification].

ackLength int 40 b

Complete MAC ack message length (in bits) (! headerLength is not added to this), only used when usage of MAC acks is enabled.

sifs double 0.000192 s

Simple interframe space (12 symbols). Time to wait between receiving a frame and acknowledging it. Should be bigger than the maximum time for switching between Tx and Rx at the receiver. Only used when usage of MAC acks is enabled.

backoffMethod string "exponential"

Backoff method to use: constant, linear or exponential

macMaxCSMABackoffs int 4

maximum number of extra backoffs (excluding the first unconditional one) before frame drop

aUnitBackoffPeriod double 0.00032 s

base unit for all backoff calculations

contentionWindow int 2

# of backoff periods of the initial contention window (for linear and constant backoff method only)

macMinBE int 3

minimum backoff exponent (for exponential backoff method only)

macMaxBE int 5

maximum backoff exponent (for exponential backoff method only)

radioModule string "^.radio"

The path to the Radio module //FIXME remove default value

Properties

Name Value Description
display i=block/rxtx
class Ieee802154Mac

Gates

Name Direction Size Description
upperLayerIn input
upperLayerOut output
lowerLayerIn input
lowerLayerOut output

Signals

Name Type Unit
linkBroken inet::Packet

Statistics

Name Title Source Record Unit Interpolation Mode
packetDropNotAddressToUs packet drop: not addressed to us packetDropReasonIsNotAddressedToUs(packetDropped) count, sum(packetBytes), vector(packetBytes) none
packetDropQueueOverflow packet drop: queue overflow packetDropReasonIsQueueOverflow(packetDropped) count, sum(packetBytes), vector(packetBytes) none
packetDropBackoffLimitReached packet drop: backoff limit reached packetDropReasonIsCongestion(packetDropped) count, sum(packetBytes), vector(packetBytes) none
packetDropRetryLimitReached packet drop: retry limit reached packetDropReasonIsRetryLimitReached(packetDropped) count, sum(packetBytes), vector(packetBytes) none
linkBroken link break linkBroken count none
packetDropIncorrectlyReceived packet drop: incorrectly received packetDropReasonIsIncorrectlyReceived(packetDropped) count, sum(packetBytes), vector(packetBytes) none

Scheduled messages (observed)

msgkindctrltagsmsgnamecontext
omnetpp::cMessage0timer-backoff
omnetpp::cMessage0timer-cca
omnetpp::cMessage0timer-rxAck
omnetpp::cMessage0timer-sifs

Direct method calls (observed)

call tofunctioninfo
MessageDispatcherinet::MessageDispatcher::arrivedarrived
InterfaceTableinet::InterfaceTable::interfaceChangedinterfaceChanged
Ieee802154NarrowbandDimensionalRadioinet::physicallayer::FlatRadioBase::setRadioModesetRadioMode
Ieee802154NarrowbandScalarRadioinet::physicallayer::FlatRadioBase::setRadioModesetRadioMode
DropTailQueueinet::queueing::PacketQueue::pullPacketpullPacket

Called methods (observed)

functioninfocall from
inet::Ieee802154Mac::handleCanPullPacketChangedhandleCanPullPacketChangedDropTailQueue
inet::Ieee802154Mac::receiveSignaltransmissionStateChangedIeee802154NarrowbandDimensionalRadio, Ieee802154NarrowbandScalarRadio

Incoming messages (observed)

gatemsgkindctrlsrcModuletags
lowerLayerInPacket0Ieee802154NarrowbandDimensionalRadioErrorRateInd, PacketProtocolTag, SignalPowerInd, SignalTimeInd, SnirInd
lowerLayerInPacket0Ieee802154NarrowbandScalarRadioErrorRateInd, PacketProtocolTag, SignalPowerInd, SignalTimeInd, SnirInd

Outgoing messages (observed)

gatemsgkindctrldestModuletags
lowerLayerOutPacket0Ieee802154NarrowbandDimensionalRadioPacketProtocolTag, DispatchProtocolInd?, InterfaceReq?, MacAddressReq?, MulticastReq?, NetworkProtocolInd?, TransportProtocolInd?
lowerLayerOutPacket0Ieee802154NarrowbandScalarRadioPacketProtocolTag, DispatchProtocolInd?, InterfaceReq?, MacAddressReq?, MulticastReq?, NetworkProtocolInd?, TransportProtocolInd?
upperLayerOutPacket0Ipv4DispatchProtocolReq, ErrorRateInd, InterfaceInd, MacAddressInd, PacketProtocolTag, SignalPowerInd, SignalTimeInd, SnirInd

Pull in messages (observed)

gatemsgkindctrlsrcModuletags
upperLayerInPacket0DropTailQueueDispatchProtocolInd, InterfaceReq, MacAddressReq, MulticastReq, NetworkProtocolInd, PacketProtocolTag, TransportProtocolInd

Packet operations (observed)

chunkTypepacketAction
Ieee802154MacHeaderinsertAtFront, peekAtFront, popAtFront

Shared Tagging operations (observed)

tagTypetagAction
DispatchProtocolReqaddTagIfAbsent
ErrorRateIndfindTag
InterfaceIndaddTagIfAbsent
MacAddressIndaddTagIfAbsent
MacAddressReqgetTag
PacketProtocolTagaddTag, addTagIfAbsent, getTag

Source code

module Ieee802154NarrowbandMac extends Ieee802154Mac
{
    parameters:
        useMACAcks = true;

        // Time needed to switch from sleep to rx.
        // TODO This is probabily wrong, since it is used to compute
        //      the time for the CCA (and that might follow an RX state)
        rxSetupTime = 0s;

        // aMaxPHYPacketSize = 127 Octets (802.15.4-2006, page 45)
        // aMinMPDUOverhead = 9 Octets (802.15.4-2006, page 159)
        // aMaxMACPayloadSize = aMaxPHYPacketSize - aMinMPDUOverhead (802.15.4-2006, page 159)
        mtu = 127 Byte - 9 Byte;

        // length of MAC header
        // aMinMPDUOverhead = 9 Octets (802.15.4-2006, page 159)
        headerLength = default(72 b);

        // Exponential Backoff
        backoffMethod = default("exponential");

        // Maximum number of frame retransmission
        // 802.15.4-2006, page 164
        macMaxFrameRetries = default(3);

        // Maximum number of extra backoffs (excluding the first unconditional one) before frame drop
        // 802.15.4-2006, page 163
        macMaxCSMABackoffs = default(4);

        // Minimum backoff exponent
        // 802.15.4-2006, page 164
        macMinBE = default(3);

        // Maximum backoff exponent
        // 802.15.4-2006, page 163
        macMaxBE = default(5);
}

File: src/inet/linklayer/ieee802154/Ieee802154NarrowbandMac.ned