IEtherMac

module interface

Interface for Ethernet MAC implementations. All Ethernet MAC implementations should implement this (i.e. declared as: EthernetCsmaMacPhy like IEtherMac). The existing implementations are these: ~EthernetCsmaMacPhy and ~EthernetMacPhy.

Doesn't do encapsulation/decapsulation; see ~EthernetEncapsulation for that.

Expected environment:

phys$i and phys$o should be connected to the "network"
upperLayerIn and upperLayerOut are usually connected to ~EthernetEncapsulation (in hosts) or ~IMacRelayUnit (in a switch)

The module does not perform encapsulation or decapsulation of frames -- this is done by higher layers (~EthernetEncapsulation).

When a frame is received from the higher layers, it must be an Ethernet frame, and with all protocol fields filled out (including the destination MAC address). The source address, if left empty, will be filled in. Then the frame is queued and transmitted according to the CSMA/CD protocol.

Data frames received from the network are Ethernet frames. They are passed to the higher layers without modification.

Also, the module properly responds to PAUSE frames, but never sends them by itself -- however, it transmits PAUSE frames received from upper layers. See PAUSE handling for more info.

Inheritance diagram

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

Implemented by

Name	Type	Description
EthernetCsmaMacPhy	compound module	Ethernet MAC layer. MAC performs transmission and reception of frames. See the ~IEtherMac for the Ethernet MAC layer general information. Doesn't do encapsulation/decapsulation; see ~Ieee8022Llc and ~EthernetEncapsulation for that.
EthernetMacPhy	compound module	Ethernet MAC which supports full-duplex operation ONLY. See the ~IEtherMac for general information.

Used in compound modules

Name	Type	Description
EthernetInterface	compound module	Represents an Ethernet network interface.
ExtUpperEthernetInterface	compound module	Provides an Ethernet network interface suitable for emulation. The upper part of the network interface is realized in the real world using a real TAP device of the host computer which is running the simulation.

Parameters

Name	Type	Description
promiscuous	bool	If true, all packets are received, otherwise only the ones with matching destination MAC address
duplexMode	bool	Selects full-duplex (true) or half-duplex (false) operation
mtu	int

Properties

Name	Value	Description
display	i=block/rxtx

Source code

//
// Interface for Ethernet MAC implementations. All Ethernet MAC implementations
// should implement this (i.e. declared as: `EthernetCsmaMacPhy` like `IEtherMac`).
// The existing implementations are these: ~EthernetCsmaMacPhy and ~EthernetMacPhy.
//
// Doesn't do encapsulation/decapsulation; see ~EthernetEncapsulation for that.
//
// Expected environment:
// - phys$i and phys$o should be connected to the "network"
// - `upperLayerIn` and `upperLayerOut` are usually connected to ~EthernetEncapsulation (in hosts)
//   or ~IMacRelayUnit (in a switch)
//
// The module does not perform encapsulation or decapsulation of frames --
// this is done by higher layers (~EthernetEncapsulation).
//
// When a frame is received from the higher layers, it must be an Ethernet frame,
// and with all protocol fields filled out (including the destination MAC address).
// The source address, if left empty, will be filled in. Then the frame is queued
// and transmitted according to the CSMA/CD protocol.
//
// Data frames received from the network are Ethernet frames. They are passed to
// the higher layers without modification.
//
// Also, the module properly responds to PAUSE frames, but never sends them
// by itself -- however, it transmits PAUSE frames received from upper layers.
// See <a href="ether-pause.html">PAUSE handling</a> for more info.
//
moduleinterface IEtherMac
{
    parameters:
        bool promiscuous;       // If true, all packets are received, otherwise only the
                                // ones with matching destination MAC address
        bool duplexMode;        // Selects full-duplex (true) or half-duplex (false) operation
        int mtu @unit(B);
        @display("i=block/rxtx");
    gates:
        input upperLayerIn @labels(EtherFrame);    // To ~EthernetEncapsulation or ~IMacRelayUnit
        output upperLayerOut @labels(EtherFrame);  // To ~EthernetEncapsulation or ~IMacRelayUnit
        inout phys @labels(EthernetSignal); // To the network
}

File: src/inet/linklayer/contract/IEthernetMac.ned