IEEE 802.11 Distributed Coordination Function

Usage diagram

The following diagram shows usage relationships between types. Unresolved types are missing from the diagram.

Used in compound modules

Name	Type	Description
Ieee80211Mac	compound module	Implementation of the 802.11b MAC protocol. This module is intended to be used in combination with the Ieee80211Radio module as the physical layer. (The SnrEval80211 and Decider80211 modules should also work if per-packet bitrate setting gets implemented.)

Parameters

Name	Type	Default value	Description
maxQueueSize	int	100	-1 means unlimited
rxModule	string
txModule	string
rateControlType	string	""
prioritizeMulticast	bool	false	if true, prioritize multicast frames (9.3.2.1 Fundamental access)

Properties

Name	Value	Description
class	Dcf
display	i=block/queue

Signals

Name	Type	Unit
NF_LINK_BREAK	inet::ieee80211::Ieee80211DataOrMgmtFrame
NF_PACKET_DROP	inet::ieee80211::Ieee80211Frame

Unassigned submodule parameters

Name	Type	Default value	Description
channelAccess.contention.initialChannelBusy	bool	true	assume that channel was busy before the simulation started
channelAccess.contention.backoffOptimization	bool	true	we can pretend the frame has arrived into the queue a little bit earlier, and may be able to start transmitting immediately
rateSelection.multicastFrameBitrate	double	-1bps
rateSelection.responseAckFrameBitrate	double	-1bps
rateSelection.responseCtsFrameBitrate	double	-1bps
rateSelection.dataFrameBitrate	double	-1bps	fastest
rateSelection.mgmtFrameBitrate	double	-1bps	fastest
rateSelection.controlFrameBitrate	double	-1bps
recoveryProcedure.shortRetryLimit	int	7
recoveryProcedure.longRetryLimit	int	4
originatorProtectionMechanism.rateSelectionModule	string
originatorAckPolicy.rateSelectionModule	string
originatorAckPolicy.ackTimeout	double	-1s
recipientAckPolicy.rateSelectionModule	string
rtsPolicy.rateSelectionModule	string
rtsPolicy.ctsTimeout	double	-1s
rtsPolicy.rtsThreshold	int	2346B
ctsPolicy.rxModule	string
ctsPolicy.rateSelectionModule	string

Source code

//
// IEEE 802.11 Distributed Coordination Function
//
module Dcf
{
    parameters:
        int maxQueueSize = default(100); // -1 means unlimited

        string rxModule;
        string txModule;
        string rateControlType = default("");
        bool prioritizeMulticast = default(false); // if true, prioritize multicast frames (9.3.2.1 Fundamental access)

        *.rateSelectionModule = "^.rateSelection";
        *.rxModule = "^." + this.rxModule;

        @class(Dcf);
        @display("i=block/queue");
        @signal[NF_LINK_BREAK](type=inet::ieee80211::Ieee80211DataOrMgmtFrame);
        @signal[NF_PACKET_DROP](type=inet::ieee80211::Ieee80211Frame);

    submodules:
        channelAccess: Dcaf {
            parameters:
                @display("p=150,100");
        }
        originatorMacDataService: OriginatorMacDataService {
            parameters:
                @display("p=150,200");
        }
        recipientMacDataService: RecipientMacDataService {
            parameters:
                @display("p=150,300");
        }
        rateSelection: RateSelection {
            parameters:
                rateControlModule = "^.rateControl";
                @display("p=400,100");
        }
        rateControl: <rateControlType> like IRateControl if rateControlType != "" {
            parameters:
                @display("p=400,200");
        }
        recoveryProcedure: NonQoSRecoveryProcedure {
            parameters:
                cwCalculatorModule = "^.channelAccess";
                rtsPolicyModule = "^.rtsPolicy";
                @display("p=400,300");
        }
        originatorProtectionMechanism: OriginatorProtectionMechanism {
            parameters:
                @display("p=400,400");
        }
        originatorAckPolicy: OriginatorAckPolicy {
            parameters:
                @display("p=650,100");
        }
        recipientAckPolicy: RecipientAckPolicy {
            parameters:
                @display("p=650,200");
        }
        rtsPolicy: RtsPolicy {
            parameters:
                @display("p=650,300");
        }
        ctsPolicy: CtsPolicy {
            parameters:
                @display("p=650,400");
        }
}

File: src/inet/linklayer/ieee80211/mac/coordinationfunction/Dcf.ned

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