NS-3 based Named Data Networking (NDN) simulator
ndnSIM 2.5: NDN, CCN, CCNx, content centric networks
API Documentation
nfd::face::Transport Class Referenceabstract

the lower part of a Face More...

#include <transport.hpp>

Inheritance diagram for nfd::face::Transport:
Collaboration diagram for nfd::face::Transport:


class  Packet
 stores a packet along with the remote endpoint More...

Public Types

typedef uint64_t EndpointId
 identifies an endpoint on the link More...
typedef TransportCounters Counters
 counters provided by Transport More...

Public Member Functions

 Transport ()
 constructor More...
virtual ~Transport ()
void setFaceAndLinkService (Face &face, LinkService &service)
 set Face and LinkService for Transport More...
const FacegetFace () const
const LinkServicegetLinkService () const
LinkServicegetLinkService ()
virtual const CountersgetCounters () const
void close ()
 request the transport to be closed More...
void send (Packet &&packet)
 send a link-layer packet More...
FaceUri getLocalUri () const
FaceUri getRemoteUri () const
ndn::nfd::FaceScope getScope () const
ndn::nfd::FacePersistency getPersistency () const
bool canChangePersistencyTo (ndn::nfd::FacePersistency newPersistency) const
 check whether the face persistency can be changed to newPersistency More...
void setPersistency (ndn::nfd::FacePersistency newPersistency)
 changes face persistency setting More...
ndn::nfd::LinkType getLinkType () const
ssize_t getMtu () const
ssize_t getSendQueueCapacity () const
TransportState getState () const
time::steady_clock::TimePoint getExpirationTime () const
virtual ssize_t getSendQueueLength ()

Public Attributes

signal::Signal< Transport, TransportState, TransportStateafterStateChange
 signals when transport state changes More...

Static Public Attributes

static constexpr ssize_t MIN_MTU = 64
 minimum MTU that may be set on a transport More...

Protected Member Functions

void receive (Packet &&packet)
 receive a link-layer packet More...
void setLocalUri (const FaceUri &uri)
void setRemoteUri (const FaceUri &uri)
void setScope (ndn::nfd::FaceScope scope)
void setLinkType (ndn::nfd::LinkType linkType)
void setMtu (ssize_t mtu)
void setSendQueueCapacity (ssize_t sendQueueCapacity)
void setState (TransportState newState)
 set transport state More...
void setExpirationTime (const time::steady_clock::TimePoint &expirationTime)
virtual bool canChangePersistencyToImpl (ndn::nfd::FacePersistency newPersistency) const
 invoked by canChangePersistencyTo to perform the check More...
virtual void afterChangePersistency (ndn::nfd::FacePersistency oldPersistency)
 invoked after the persistency has been changed More...
virtual void doClose ()=0
 performs Transport specific operations to close the transport More...

Additional Inherited Members

- Protected Attributes inherited from nfd::face::TransportCounters
PacketCounter nInPackets
 count of incoming packets More...
PacketCounter nOutPackets
 count of outgoing packets More...
ByteCounter nInBytes
 total incoming bytes More...
ByteCounter nOutBytes
 total outgoing bytes More...

Detailed Description

the lower part of a Face

See also

Definition at line 113 of file transport.hpp.

Member Typedef Documentation

◆ EndpointId

identifies an endpoint on the link

Definition at line 118 of file transport.hpp.

◆ Counters

counters provided by Transport

Definition at line 146 of file transport.hpp.

Constructor & Destructor Documentation

◆ Transport()

nfd::face::Transport::Transport ( )


Transport constructor initializes static properties to invalid values. Subclass constructor must explicitly set every static property.

This constructor initializes TransportState to UP; subclass constructor can rely on this default value.

Definition at line 61 of file transport.cpp.

◆ ~Transport()

nfd::face::Transport::~Transport ( )

Member Function Documentation

◆ setFaceAndLinkService()

void nfd::face::Transport::setFaceAndLinkService ( Face face,
LinkService service 

set Face and LinkService for Transport

setFaceAndLinkService has not been called

Definition at line 77 of file transport.cpp.

◆ getFace()

const Face * nfd::face::Transport::getFace ( ) const
Face to which this Transport is attached

Definition at line 391 of file transport.hpp.

Referenced by nfd::face::operator<<().

◆ getLinkService() [1/2]

const LinkService * nfd::face::Transport::getLinkService ( ) const
LinkService to which this Transport is attached

Definition at line 397 of file transport.hpp.

◆ getLinkService() [2/2]

LinkService * nfd::face::Transport::getLinkService ( )
LinkService to which this Transport is attached

Definition at line 403 of file transport.hpp.

◆ getCounters()

const Transport::Counters & nfd::face::Transport::getCounters ( ) const

Reimplemented in nfd::face::WebSocketTransport.

Definition at line 409 of file transport.hpp.

◆ close()

void nfd::face::Transport::close ( )

request the transport to be closed

This operation is effective only if transport is in UP or DOWN state, otherwise it has no effect. The transport changes state to CLOSING, and performs cleanup procedure. The state will be changed to CLOSED when cleanup is complete, which may happen synchronously or asynchronously.

Definition at line 87 of file transport.cpp.

References nfd::face::CLOSING, doClose(), nfd::face::DOWN, setState(), and nfd::face::UP.

◆ send()

void nfd::face::Transport::send ( Packet &&  packet)

send a link-layer packet

This operation has no effect if getState() is neither UP nor DOWN
undefined behavior if packet size exceeds MTU limit

Definition at line 100 of file transport.cpp.

References nfd::face::DOWN, getMtu(), getState(), nfd::face::MTU_UNLIMITED, NFD_LOG_FACE_TRACE, nfd::face::TransportCounters::nOutBytes, nfd::face::TransportCounters::nOutPackets, and nfd::face::UP.

Referenced by nfd::face::LinkService::sendPacket().

◆ getLocalUri()

FaceUri nfd::face::Transport::getLocalUri ( ) const
a FaceUri representing local endpoint

Definition at line 415 of file transport.hpp.

Referenced by ns3::ndn::NetDeviceTransport::NetDeviceTransport(), and nfd::face::operator<<().

◆ getRemoteUri()

FaceUri nfd::face::Transport::getRemoteUri ( ) const
a FaceUri representing remote endpoint

Definition at line 427 of file transport.hpp.

Referenced by nfd::face::operator<<().

◆ getScope()

ndn::nfd::FaceScope nfd::face::Transport::getScope ( ) const
whether face is local or non-local for scope control purpose

Definition at line 439 of file transport.hpp.

◆ getPersistency()

◆ canChangePersistencyTo()

bool nfd::face::Transport::canChangePersistencyTo ( ndn::nfd::FacePersistency  newPersistency) const

check whether the face persistency can be changed to newPersistency

This function serves as the external API, and invokes the protected function canChangePersistencyToImpl to perform further checks if newPersistency differs from the current persistency.

true if the change can be performed, false otherwise

Definition at line 132 of file transport.cpp.

References canChangePersistencyToImpl(), ndn::nfd::FACE_PERSISTENCY_NONE, and NFD_LOG_FACE_TRACE.

Referenced by setPersistency().

◆ setPersistency()

◆ getLinkType()

ndn::nfd::LinkType nfd::face::Transport::getLinkType ( ) const
whether face is point-to-point or multi-access

Definition at line 457 of file transport.hpp.

◆ getMtu()

ssize_t nfd::face::Transport::getMtu ( ) const
maximum payload size
Return values
MTU_UNLIMITEDtransport has no limit on payload size

This size is the maximum packet size that can be sent or received through this transport.

For a datagram-based transport, this is typically the Maximum Transmission Unit (MTU), after the overhead of headers introduced by the transport has been accounted for. For a stream-based transport, this is typically unlimited (MTU_UNLIMITED).

Definition at line 469 of file transport.hpp.

Referenced by receive(), send(), and nfd::face::UnicastUdpTransport::UnicastUdpTransport().

◆ getSendQueueCapacity()

ssize_t nfd::face::Transport::getSendQueueCapacity ( ) const
capacity of the send queue (in bytes)
Return values
QUEUE_UNSUPPORTEDtransport does not support queue capacity retrieval
QUEUE_ERRORtransport was unable to retrieve the queue capacity

Definition at line 482 of file transport.hpp.

◆ getState()

TransportState nfd::face::Transport::getState ( ) const
transport state

Definition at line 494 of file transport.hpp.

Referenced by nfd::face::TcpTransport::afterChangePersistency(), and send().

◆ getExpirationTime()

time::steady_clock::TimePoint nfd::face::Transport::getExpirationTime ( ) const
expiration time of the transport
Return values
time::steady_clock::TimePoint::max()the transport has indefinite lifetime

Definition at line 500 of file transport.hpp.

◆ getSendQueueLength()

virtual ssize_t nfd::face::Transport::getSendQueueLength ( )

◆ receive()

void nfd::face::Transport::receive ( Packet &&  packet)

◆ setLocalUri()

◆ setRemoteUri()

◆ setScope()

◆ setLinkType()

◆ setMtu()

◆ setSendQueueCapacity()

void nfd::face::Transport::setSendQueueCapacity ( ssize_t  sendQueueCapacity)

◆ setState()

void nfd::face::Transport::setState ( TransportState  newState)

set transport state

Only the following transitions are valid: UP->DOWN, DOWN->UP, UP/DOWN->CLOSING/FAILED, CLOSING/FAILED->CLOSED

std::runtime_errortransition is invalid.

Definition at line 177 of file transport.cpp.

References afterStateChange, nfd::face::CLOSED, nfd::face::CLOSING, nfd::face::DOWN, nfd::face::FAILED, NFD_LOG_FACE_INFO, and nfd::face::UP.

Referenced by nfd::face::TcpTransport::afterChangePersistency(), close(), nfd::face::EthernetTransport::doClose(), nfd::face::InternalForwarderTransport::doClose(), nfd::face::WebSocketTransport::doClose(), nfd::face::TcpTransport::handleError(), and nfd::face::WebSocketTransport::handlePongTimeout().

◆ setExpirationTime()

void nfd::face::Transport::setExpirationTime ( const time::steady_clock::TimePoint expirationTime)

◆ canChangePersistencyToImpl()

bool nfd::face::Transport::canChangePersistencyToImpl ( ndn::nfd::FacePersistency  newPersistency) const

invoked by canChangePersistencyTo to perform the check

Base class implementation returns false.

newPersistencythe new persistency, guaranteed to be different from current persistency

Reimplemented in nfd::face::TcpTransport, nfd::face::UnicastEthernetTransport, and nfd::face::UnicastUdpTransport.

Definition at line 148 of file transport.cpp.

Referenced by canChangePersistencyTo().

◆ afterChangePersistency()

void nfd::face::Transport::afterChangePersistency ( ndn::nfd::FacePersistency  oldPersistency)

invoked after the persistency has been changed

The base class implementation does nothing. When overridden in a subclass, the function should update internal states after persistency setting has been changed.

Reimplemented in nfd::face::TcpTransport, nfd::face::UnicastEthernetTransport, and nfd::face::UnicastUdpTransport.

Definition at line 172 of file transport.cpp.

Referenced by setPersistency().

◆ doClose()

virtual void nfd::face::Transport::doClose ( )
protectedpure virtual

performs Transport specific operations to close the transport

This is invoked once by close() after changing state to CLOSING. It will not be invoked by Transport class if the transport is already CLOSING or CLOSED.

When the cleanup procedure is complete, this method should change state to CLOSED. This transition can happen synchronously or asynchronously.

Implemented in nfd::face::WebSocketTransport, nfd::face::InternalForwarderTransport, nfd::face::DatagramTransport< Protocol, Addressing >, nfd::face::DatagramTransport< boost::asio::ip::udp, Unicast >, nfd::face::DatagramTransport< boost::asio::ip::udp, Multicast >, nfd::face::EthernetTransport, nfd::face::StreamTransport< Protocol >, nfd::face::TcpTransport, nfd::face::StreamTransport< boost::asio::ip::tcp >, and nfd::face::StreamTransport< boost::asio::local::stream_protocol >.

Referenced by close().

Member Data Documentation

◆ afterStateChange

signal::Signal<Transport, TransportState, TransportState> nfd::face::Transport::afterStateChange

signals when transport state changes

Definition at line 274 of file transport.hpp.

Referenced by nfd::face::InternalClientTransport::connectToForwarder(), and setState().


const ssize_t nfd::face::Transport::MIN_MTU = 64

minimum MTU that may be set on a transport

This is done to ensure the NDNLPv2 fragmentation feature functions properly.

Definition at line 374 of file transport.hpp.

Referenced by nfd::face::UnicastUdpTransport::UnicastUdpTransport().

The documentation for this class was generated from the following files: