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	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
displayStringTextFormat	string	""	Determines the text that is written on top of the submodule, supports displaying pars, watches, and module-specific information
interfaceTableModule	string
address	string	"auto"	MAC address as a 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 set up the radio to the reception state
aTurnaroundTime	double	0.000192 s	Time to switch the radio from Rx to Tx state
useMACAcks	bool	true	Send/Expect MAC acks for unicast traffic?
macMaxFrameRetries	int	3	Maximum number of frame retransmissions, only used when the 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 the usage of MAC acks is enabled. The 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 versa). This gives the value 192us + 352us = 544us (there has 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 the 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 the 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	Number 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
class	Ieee802154Mac
display	i=block/rxtx

Gates

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

Signals

Name	Type	Unit	Description
linkBroken	inet::Packet

Statistics

Name	Title	Source	Record	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

Source code

module Ieee802154NarrowbandMac extends Ieee802154Mac
{
    parameters:
        useMACAcks = true;

        // Time needed to switch from sleep to rx.
        // TODO This is probably 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