Path MTU Discovery controller for QUIC (RFC 8899 DPLPMTUD) More...

#include <pmtud_controller.h>

Collaboration diagram for kcenon::network::protocols::quic::pmtud_controller:

Public Member Functions
	pmtud_controller ()
	Default constructor with default configuration.

	pmtud_controller (pmtud_config config)
	Constructor with custom configuration.

auto	current_mtu () const noexcept -> size_t
	Get current validated MTU.

auto	min_mtu () const noexcept -> size_t
	Get minimum MTU.

auto	max_mtu () const noexcept -> size_t
	Get maximum MTU being probed.

auto	state () const noexcept -> pmtud_state
	Get current PMTUD state.

auto	is_enabled () const noexcept -> bool
	Check if PMTUD is enabled.

auto	is_search_complete () const noexcept -> bool
	Check if MTU search is complete.

void	enable ()
	Enable PMTUD and start probing.

void	disable ()
	Disable PMTUD.

void	reset ()
	Reset to initial state.

auto	should_probe (std::chrono::steady_clock::time_point now) const noexcept -> bool
	Check if a probe should be sent.

auto	probe_size () const noexcept -> std::optional< size_t >
	Get the size for next probe packet.

void	on_probe_sent (size_t size, std::chrono::steady_clock::time_point sent_time)
	Record that a probe was sent.

void	on_probe_acked (size_t size)
	Handle probe acknowledgment.

void	on_probe_lost (size_t size)
	Handle probe loss.

void	on_packet_too_big (size_t reported_mtu)
	Handle ICMP Packet Too Big message.

auto	next_timeout () const noexcept -> std::optional< std::chrono::steady_clock::time_point >
	Get next timeout deadline for PMTUD.

void	on_timeout (std::chrono::steady_clock::time_point now)
	Handle timeout event.

Private Member Functions
void	start_search ()
	Start probing from base MTU.

auto	calculate_next_probe_size () const noexcept -> size_t
	Calculate next probe size using binary search.

void	complete_search ()
	Transition to search_complete state.

void	handle_black_hole ()
	Handle black hole detection.

Private Attributes
pmtud_config	config_
	Configuration.

pmtud_state	state_ {pmtud_state::disabled}
	Current state.

size_t	current_mtu_
	Current validated MTU.

size_t	search_low_
	Lower bound for binary search (known good MTU)

size_t	search_high_
	Upper bound for binary search (target MTU)

size_t	probing_mtu_ {0}
	Current probe size being tested.

size_t	probe_count_ {0}
	Number of probes sent at current size.

size_t	consecutive_failures_ {0}
	Number of consecutive probe failures (for black hole detection)

std::chrono::steady_clock::time_point	last_probe_time_
	Time of last probe sent.

std::chrono::steady_clock::time_point	search_complete_time_
	Time when search was completed (for re-validation)

bool	probe_in_flight_ {false}
	Whether a probe is currently in flight.

Static Private Attributes
static constexpr size_t	kBlackHoleThreshold = 6
	Threshold for black hole detection.

Detailed Description

Path MTU Discovery controller for QUIC (RFC 8899 DPLPMTUD)

Implements Datagram Packetization Layer PMTU Discovery (DPLPMTUD) as specified in RFC 8899 for use with QUIC (RFC 9000 Section 14).

The controller maintains a state machine that:

Starts at the minimum QUIC MTU (1200 bytes)
Probes for larger MTU using binary search
Handles probe acknowledgments and losses
Responds to ICMP Packet Too Big messages
Periodically re-validates discovered MTU

Definition at line 74 of file pmtud_controller.h.

Constructor & Destructor Documentation

◆ pmtud_controller() [1/2]

kcenon::network::protocols::quic::pmtud_controller::pmtud_controller ( )

Default constructor with default configuration.

Definition at line 30 of file pmtud_controller.cpp.

    : pmtud_controller(pmtud_config{})
{
}

◆ pmtud_controller() [2/2]

kcenon::network::protocols::quic::pmtud_controller::pmtud_controller ( pmtud_config config )

explicit

Constructor with custom configuration.

Parameters

config Configuration parameters

Definition at line 35 of file pmtud_controller.cpp.

    : config_(config)
    , current_mtu_(config_.min_mtu)
    , search_low_(config_.min_mtu)
    , search_high_(config_.max_probe_mtu)
{
}

References config.

Member Function Documentation

◆ calculate_next_probe_size()

auto kcenon::network::protocols::quic::pmtud_controller::calculate_next_probe_size ( ) const -> size_t

nodiscardprivatenoexcept

Calculate next probe size using binary search.

Returns: Next MTU to probe

Definition at line 315 of file pmtud_controller.cpp.

{
    // Binary search - probe the midpoint
    size_t mid = search_low_ + (search_high_ - search_low_) / 2;
 
    // Round up to ensure we make progress
    if (mid == search_low_ && search_high_ > search_low_)
    {
        mid = search_low_ + config_.probe_step;
    }
 
    return std::min(mid, search_high_);
}

References config_, kcenon::network::protocols::quic::pmtud_config::probe_step, search_high_, and search_low_.

Referenced by on_packet_too_big(), on_probe_acked(), on_probe_lost(), and start_search().

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◆ complete_search()

void kcenon::network::protocols::quic::pmtud_controller::complete_search ( )

private

Transition to search_complete state.

Definition at line 329 of file pmtud_controller.cpp.

{
    state_ = pmtud_state::search_complete;
    search_complete_time_ = std::chrono::steady_clock::now();
    probing_mtu_ = 0;
    probe_count_ = 0;
}

References probe_count_, probing_mtu_, kcenon::network::protocols::quic::search_complete, search_complete_time_, and state_.

Referenced by on_probe_acked(), and on_probe_lost().

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◆ current_mtu()

auto kcenon::network::protocols::quic::pmtud_controller::current_mtu ( ) const -> size_t

inlinenodiscardnoexcept

Get current validated MTU.

Returns: Current MTU to use for sending packets

Definition at line 96 of file pmtud_controller.h.

    {
        return current_mtu_;
    }

References current_mtu_.

Referenced by kcenon::network::protocols::quic::connection::enable_pmtud(), and kcenon::network::protocols::quic::connection::path_mtu().

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◆ disable()

void kcenon::network::protocols::quic::pmtud_controller::disable ( )

Disable PMTUD.

Stops probing and reverts to minimum MTU.

Definition at line 58 of file pmtud_controller.cpp.

{
    state_ = pmtud_state::disabled;
    current_mtu_ = config_.min_mtu;
    probing_mtu_ = 0;
    probe_in_flight_ = false;
}

References config_, current_mtu_, kcenon::network::protocols::quic::disabled, kcenon::network::protocols::quic::pmtud_config::min_mtu, probe_in_flight_, probing_mtu_, and state_.

Referenced by kcenon::network::protocols::quic::connection::disable_pmtud().

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◆ enable()

void kcenon::network::protocols::quic::pmtud_controller::enable ( )

Enable PMTUD and start probing.

Transitions from disabled state to base state and begins the MTU discovery process.

Definition at line 43 of file pmtud_controller.cpp.

{
    if (state_ == pmtud_state::disabled)
    {
        state_ = pmtud_state::base;
        current_mtu_ = config_.min_mtu;
        search_low_ = config_.min_mtu;
        search_high_ = config_.max_probe_mtu;
        probe_count_ = 0;
        consecutive_failures_ = 0;
        probe_in_flight_ = false;
        start_search();
    }
}

References kcenon::network::protocols::quic::base, config_, consecutive_failures_, current_mtu_, kcenon::network::protocols::quic::disabled, kcenon::network::protocols::quic::pmtud_config::max_probe_mtu, kcenon::network::protocols::quic::pmtud_config::min_mtu, probe_count_, probe_in_flight_, search_high_, search_low_, start_search(), and state_.

Referenced by kcenon::network::protocols::quic::connection::enable_pmtud().

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◆ handle_black_hole()

void kcenon::network::protocols::quic::pmtud_controller::handle_black_hole ( )

private

Handle black hole detection.

Definition at line 337 of file pmtud_controller.cpp.

{
    // Black hole detected - reset to minimum MTU
    state_ = pmtud_state::error;
    current_mtu_ = config_.min_mtu;
    search_low_ = config_.min_mtu;
    search_high_ = config_.max_probe_mtu;
    probing_mtu_ = 0;
    probe_count_ = 0;
    consecutive_failures_ = 0;
    probe_in_flight_ = false;
}

References config_, consecutive_failures_, current_mtu_, kcenon::network::protocols::quic::error, kcenon::network::protocols::quic::pmtud_config::max_probe_mtu, kcenon::network::protocols::quic::pmtud_config::min_mtu, probe_count_, probe_in_flight_, probing_mtu_, search_high_, search_low_, and state_.

Referenced by on_packet_too_big(), and on_probe_lost().

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◆ is_enabled()

auto kcenon::network::protocols::quic::pmtud_controller::is_enabled ( ) const -> bool

inlinenodiscardnoexcept

Check if PMTUD is enabled.

Returns: True if PMTUD is enabled and running

Definition at line 136 of file pmtud_controller.h.

    {
        return state_ != pmtud_state::disabled;
    }

References kcenon::network::protocols::quic::disabled, and state_.

Referenced by kcenon::network::protocols::quic::connection::pmtud_enabled().

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◆ is_search_complete()

auto kcenon::network::protocols::quic::pmtud_controller::is_search_complete ( ) const -> bool

inlinenodiscardnoexcept

Check if MTU search is complete.

Returns: True if maximum MTU has been found

Definition at line 145 of file pmtud_controller.h.

    {
        return state_ == pmtud_state::search_complete;
    }

References kcenon::network::protocols::quic::search_complete, and state_.

◆ max_mtu()

auto kcenon::network::protocols::quic::pmtud_controller::max_mtu ( ) const -> size_t

inlinenodiscardnoexcept

Get maximum MTU being probed.

Returns: Maximum MTU target

Definition at line 114 of file pmtud_controller.h.

    {
        return config_.max_probe_mtu;
    }

References config_, and kcenon::network::protocols::quic::pmtud_config::max_probe_mtu.

◆ min_mtu()

auto kcenon::network::protocols::quic::pmtud_controller::min_mtu ( ) const -> size_t

inlinenodiscardnoexcept

Get minimum MTU.

Returns: Minimum guaranteed MTU (BASE_PLPMTU)

Definition at line 105 of file pmtud_controller.h.

    {
        return config_.min_mtu;
    }

References config_, and kcenon::network::protocols::quic::pmtud_config::min_mtu.

Referenced by kcenon::network::protocols::quic::connection::disable_pmtud().

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◆ next_timeout()

auto kcenon::network::protocols::quic::pmtud_controller::next_timeout ( ) const -> std::optional<std::chrono::steady_clock::time_point>

nodiscardnoexcept

Get next timeout deadline for PMTUD.

Returns: Time point for next probe or confirmation, or nullopt if none

Definition at line 256 of file pmtud_controller.cpp.

{
    if (state_ == pmtud_state::disabled)
    {
        return std::nullopt;
    }
 
    if (probe_in_flight_)
    {
        // Timeout for probe in flight
        return last_probe_time_ + config_.probe_timeout;
    }
 
    if (state_ == pmtud_state::searching || state_ == pmtud_state::base)
    {
        return last_probe_time_ + config_.probe_interval;
    }
 
    if (state_ == pmtud_state::search_complete)
    {
        return search_complete_time_ + config_.confirmation_interval;
    }
 
    if (state_ == pmtud_state::error)
    {
        return last_probe_time_ + config_.probe_timeout;
    }
 
    return std::nullopt;
}

◆ on_packet_too_big()

void kcenon::network::protocols::quic::pmtud_controller::on_packet_too_big ( size_t reported_mtu )

Handle ICMP Packet Too Big message.

Parameters

reported_mtu MTU reported in the ICMP message

Called when an ICMP PTB message is received. Updates the MTU immediately if the reported value is smaller.

Definition at line 233 of file pmtud_controller.cpp.

{
    // RFC 8899: ICMP PTB should trigger immediate MTU reduction
    if (reported_mtu >= config_.min_mtu && reported_mtu < current_mtu_)
    {
        current_mtu_ = reported_mtu;
        search_high_ = reported_mtu;
 
        if (state_ == pmtud_state::search_complete)
        {
            // Need to restart search with new upper bound
            state_ = pmtud_state::searching;
            probe_count_ = 0;
            probing_mtu_ = calculate_next_probe_size();
        }
    }
    else if (reported_mtu < config_.min_mtu)
    {
        // PTB reports MTU below QUIC minimum - possible black hole
        handle_black_hole();
    }
}

References calculate_next_probe_size(), config_, current_mtu_, handle_black_hole(), kcenon::network::protocols::quic::pmtud_config::min_mtu, probe_count_, probing_mtu_, kcenon::network::protocols::quic::search_complete, search_high_, kcenon::network::protocols::quic::searching, and state_.

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◆ on_probe_acked()

void kcenon::network::protocols::quic::pmtud_controller::on_probe_acked ( size_t size )

Handle probe acknowledgment.

Parameters

size	Size of the probed packet that was acknowledged

Called when a probe packet is acknowledged by the peer. If the probed size is larger than current MTU, updates the validated MTU and continues searching.

Definition at line 147 of file pmtud_controller.cpp.

{
    probe_in_flight_ = false;
    consecutive_failures_ = 0;
 
    // Handle based on current state
    if (state_ == pmtud_state::base || state_ == pmtud_state::searching)
    {
        // Successful probe - update validated MTU
        if (size > current_mtu_)
        {
            current_mtu_ = size;
            search_low_ = size;
        }
 
        // Check if we've found the maximum
        if (search_high_ - search_low_ <= config_.probe_step)
        {
            complete_search();
        }
        else
        {
            // Continue searching
            state_ = pmtud_state::searching;
            probe_count_ = 0;
            probing_mtu_ = calculate_next_probe_size();
        }
    }
    else if (state_ == pmtud_state::search_complete)
    {
        // Re-validation successful
        search_complete_time_ = std::chrono::steady_clock::now();
    }
    else if (state_ == pmtud_state::error)
    {
        // Recovery successful
        state_ = pmtud_state::searching;
        probe_count_ = 0;
        probing_mtu_ = calculate_next_probe_size();
    }
}

References kcenon::network::protocols::quic::base, calculate_next_probe_size(), complete_search(), config_, consecutive_failures_, current_mtu_, kcenon::network::protocols::quic::error, probe_count_, probe_in_flight_, kcenon::network::protocols::quic::pmtud_config::probe_step, probing_mtu_, kcenon::network::protocols::quic::search_complete, search_complete_time_, search_high_, search_low_, kcenon::network::protocols::quic::searching, and state_.

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◆ on_probe_lost()

void kcenon::network::protocols::quic::pmtud_controller::on_probe_lost ( size_t size )

Handle probe loss.

Parameters

size	Size of the probe packet that was lost

Called when a probe packet is declared lost. Adjusts the search range and may retry probing.

Definition at line 189 of file pmtud_controller.cpp.

{
    probe_in_flight_ = false;
    ++consecutive_failures_;
 
    // Check for black hole
    if (consecutive_failures_ >= kBlackHoleThreshold)
    {
        handle_black_hole();
        return;
    }
 
    if (state_ == pmtud_state::base || state_ == pmtud_state::searching)
    {
        if (probe_count_ >= config_.max_probes)
        {
            // Too many failures at this size - reduce search range
            search_high_ = size;
            probe_count_ = 0;
 
            // Check if we've converged
            if (search_high_ - search_low_ <= config_.probe_step)
            {
                complete_search();
            }
            else
            {
                probing_mtu_ = calculate_next_probe_size();
            }
        }
        // Otherwise, will retry the same size on next should_probe()
    }
    else if (state_ == pmtud_state::search_complete)
    {
        // Re-validation failed - MTU may have decreased
        // Fall back to error state and restart search
        state_ = pmtud_state::error;
        search_high_ = current_mtu_;
        search_low_ = config_.min_mtu;
        current_mtu_ = config_.min_mtu;
        probe_count_ = 0;
    }
}

References kcenon::network::protocols::quic::base, calculate_next_probe_size(), complete_search(), config_, consecutive_failures_, current_mtu_, kcenon::network::protocols::quic::error, handle_black_hole(), kBlackHoleThreshold, kcenon::network::protocols::quic::pmtud_config::max_probes, kcenon::network::protocols::quic::pmtud_config::min_mtu, probe_count_, probe_in_flight_, kcenon::network::protocols::quic::pmtud_config::probe_step, probing_mtu_, kcenon::network::protocols::quic::search_complete, search_high_, search_low_, kcenon::network::protocols::quic::searching, and state_.

Referenced by on_timeout().

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◆ on_probe_sent()

void kcenon::network::protocols::quic::pmtud_controller::on_probe_sent	(	size_t	size,
		std::chrono::steady_clock::time_point	sent_time )

Record that a probe was sent.

Parameters

size	Size of the probe packet sent
sent_time	Time the probe was sent

Definition at line 138 of file pmtud_controller.cpp.

{
    probing_mtu_ = size;
    last_probe_time_ = sent_time;
    probe_in_flight_ = true;
    ++probe_count_;
}

References last_probe_time_, probe_count_, probe_in_flight_, and probing_mtu_.

◆ on_timeout()

void kcenon::network::protocols::quic::pmtud_controller::on_timeout ( std::chrono::steady_clock::time_point now )

Handle timeout event.

Parameters

now	Current time

Called when the PMTUD timer expires. May trigger probe retransmission or state transitions.

Definition at line 288 of file pmtud_controller.cpp.

{
    if (state_ == pmtud_state::disabled)
    {
        return;
    }
 
    if (probe_in_flight_)
    {
        // Probe timeout - treat as loss
        auto elapsed = now - last_probe_time_;
        if (elapsed >= config_.probe_timeout)
        {
            on_probe_lost(probing_mtu_);
        }
    }
}

References config_, kcenon::network::protocols::quic::disabled, last_probe_time_, on_probe_lost(), probe_in_flight_, kcenon::network::protocols::quic::pmtud_config::probe_timeout, probing_mtu_, and state_.

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◆ probe_size()

auto kcenon::network::protocols::quic::pmtud_controller::probe_size ( ) const -> std::optional<size_t>

nodiscardnoexcept

Get the size for next probe packet.

Returns: Size in bytes for the probe packet, or nullopt if no probe needed

Definition at line 117 of file pmtud_controller.cpp.

{
    if (state_ == pmtud_state::disabled)
    {
        return std::nullopt;
    }
 
    if (state_ == pmtud_state::base || state_ == pmtud_state::searching)
    {
        return probing_mtu_ > 0 ? std::optional<size_t>(probing_mtu_) : std::nullopt;
    }
 
    // For re-validation in search_complete state
    if (state_ == pmtud_state::search_complete)
    {
        return current_mtu_;
    }
 
    return std::nullopt;
}

References kcenon::network::protocols::quic::base, current_mtu_, kcenon::network::protocols::quic::disabled, probing_mtu_, kcenon::network::protocols::quic::search_complete, kcenon::network::protocols::quic::searching, and state_.

◆ reset()

void kcenon::network::protocols::quic::pmtud_controller::reset ( )

Reset to initial state.

Clears all state and restarts discovery from minimum MTU.

Definition at line 66 of file pmtud_controller.cpp.

{
    state_ = pmtud_state::disabled;
    current_mtu_ = config_.min_mtu;
    search_low_ = config_.min_mtu;
    search_high_ = config_.max_probe_mtu;
    probing_mtu_ = 0;
    probe_count_ = 0;
    consecutive_failures_ = 0;
    probe_in_flight_ = false;
}

References config_, consecutive_failures_, current_mtu_, kcenon::network::protocols::quic::disabled, kcenon::network::protocols::quic::pmtud_config::max_probe_mtu, kcenon::network::protocols::quic::pmtud_config::min_mtu, probe_count_, probe_in_flight_, probing_mtu_, search_high_, search_low_, and state_.

◆ should_probe()

auto kcenon::network::protocols::quic::pmtud_controller::should_probe ( std::chrono::steady_clock::time_point now ) const -> bool

nodiscardnoexcept

Check if a probe should be sent.

Parameters

now	Current time

Returns: True if a probe packet should be generated

Definition at line 78 of file pmtud_controller.cpp.

{
    // Don't probe if disabled or probe already in flight
    if (state_ == pmtud_state::disabled || probe_in_flight_)
    {
        return false;
    }
 
    // In base state, always ready to start probing
    if (state_ == pmtud_state::base)
    {
        return true;
    }
 
    // In searching state, check if enough time has passed
    if (state_ == pmtud_state::searching)
    {
        auto elapsed = now - last_probe_time_;
        return elapsed >= config_.probe_interval;
    }
 
    // In search_complete state, check if re-validation is needed
    if (state_ == pmtud_state::search_complete)
    {
        auto elapsed = now - search_complete_time_;
        return elapsed >= config_.confirmation_interval;
    }
 
    // In error state, check if enough time for recovery
    if (state_ == pmtud_state::error)
    {
        auto elapsed = now - last_probe_time_;
        return elapsed >= config_.probe_timeout;
    }
 
    return false;
}

References kcenon::network::protocols::quic::base, kcenon::network::protocols::quic::disabled, kcenon::network::protocols::quic::error, kcenon::network::protocols::quic::search_complete, and kcenon::network::protocols::quic::searching.

◆ start_search()

void kcenon::network::protocols::quic::pmtud_controller::start_search ( )

private

Start probing from base MTU.

Definition at line 306 of file pmtud_controller.cpp.

{
    state_ = pmtud_state::searching;
    search_low_ = current_mtu_;
    search_high_ = config_.max_probe_mtu;
    probe_count_ = 0;
    probing_mtu_ = calculate_next_probe_size();
}

References calculate_next_probe_size(), config_, current_mtu_, kcenon::network::protocols::quic::pmtud_config::max_probe_mtu, probe_count_, probing_mtu_, search_high_, search_low_, kcenon::network::protocols::quic::searching, and state_.

Referenced by enable().

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◆ state()

auto kcenon::network::protocols::quic::pmtud_controller::state ( ) const -> pmtud_state

inlinenodiscardnoexcept

Get current PMTUD state.

Returns: Current state

Definition at line 127 of file pmtud_controller.h.

    {
        return state_;
    }

References state_.

Member Data Documentation

◆ config_

pmtud_config kcenon::network::protocols::quic::pmtud_controller::config_

private

Configuration.

Definition at line 284 of file pmtud_controller.h.

Referenced by calculate_next_probe_size(), disable(), enable(), handle_black_hole(), max_mtu(), min_mtu(), next_timeout(), on_packet_too_big(), on_probe_acked(), on_probe_lost(), on_timeout(), reset(), and start_search().

◆ consecutive_failures_

size_t kcenon::network::protocols::quic::pmtud_controller::consecutive_failures_ {0}

private

Number of consecutive probe failures (for black hole detection)

Definition at line 305 of file pmtud_controller.h.

305{0};

Referenced by enable(), handle_black_hole(), on_probe_acked(), on_probe_lost(), and reset().

◆ current_mtu_

size_t kcenon::network::protocols::quic::pmtud_controller::current_mtu_

private

Current validated MTU.

Definition at line 290 of file pmtud_controller.h.

Referenced by current_mtu(), disable(), enable(), handle_black_hole(), on_packet_too_big(), on_probe_acked(), on_probe_lost(), probe_size(), reset(), and start_search().

◆ kBlackHoleThreshold

size_t kcenon::network::protocols::quic::pmtud_controller::kBlackHoleThreshold = 6

staticconstexprprivate

Threshold for black hole detection.

Definition at line 317 of file pmtud_controller.h.

Referenced by on_probe_lost().

◆ last_probe_time_

std::chrono::steady_clock::time_point kcenon::network::protocols::quic::pmtud_controller::last_probe_time_

private

Time of last probe sent.

Definition at line 308 of file pmtud_controller.h.

Referenced by next_timeout(), on_probe_sent(), and on_timeout().

◆ probe_count_

size_t kcenon::network::protocols::quic::pmtud_controller::probe_count_ {0}

private

Number of probes sent at current size.

Definition at line 302 of file pmtud_controller.h.

302{0};

Referenced by complete_search(), enable(), handle_black_hole(), on_packet_too_big(), on_probe_acked(), on_probe_lost(), on_probe_sent(), reset(), and start_search().

◆ probe_in_flight_

bool kcenon::network::protocols::quic::pmtud_controller::probe_in_flight_ {false}

private

Whether a probe is currently in flight.

Definition at line 314 of file pmtud_controller.h.

314{false};

Referenced by disable(), enable(), handle_black_hole(), next_timeout(), on_probe_acked(), on_probe_lost(), on_probe_sent(), on_timeout(), and reset().

◆ probing_mtu_

size_t kcenon::network::protocols::quic::pmtud_controller::probing_mtu_ {0}

private

Current probe size being tested.

Definition at line 299 of file pmtud_controller.h.

299{0};

Referenced by complete_search(), disable(), handle_black_hole(), on_packet_too_big(), on_probe_acked(), on_probe_lost(), on_probe_sent(), on_timeout(), probe_size(), reset(), and start_search().

◆ search_complete_time_

std::chrono::steady_clock::time_point kcenon::network::protocols::quic::pmtud_controller::search_complete_time_

private

Time when search was completed (for re-validation)

Definition at line 311 of file pmtud_controller.h.

Referenced by complete_search(), next_timeout(), and on_probe_acked().

◆ search_high_

size_t kcenon::network::protocols::quic::pmtud_controller::search_high_

private

Upper bound for binary search (target MTU)

Definition at line 296 of file pmtud_controller.h.

Referenced by calculate_next_probe_size(), enable(), handle_black_hole(), on_packet_too_big(), on_probe_acked(), on_probe_lost(), reset(), and start_search().

◆ search_low_

size_t kcenon::network::protocols::quic::pmtud_controller::search_low_

private

Lower bound for binary search (known good MTU)

Definition at line 293 of file pmtud_controller.h.

Referenced by calculate_next_probe_size(), enable(), handle_black_hole(), on_probe_acked(), on_probe_lost(), reset(), and start_search().

◆ state_

pmtud_state kcenon::network::protocols::quic::pmtud_controller::state_ {pmtud_state::disabled}

private

Current state.

Definition at line 287 of file pmtud_controller.h.

287{pmtud_state::disabled};

Referenced by complete_search(), disable(), enable(), handle_black_hole(), is_enabled(), is_search_complete(), next_timeout(), on_packet_too_big(), on_probe_acked(), on_probe_lost(), on_timeout(), probe_size(), reset(), start_search(), and state().

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

src/internal/protocols/quic/pmtud_controller.h
src/protocols/quic/pmtud_controller.cpp

Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ pmtud_controller() [1/2]

◆ pmtud_controller() [2/2]

Member Function Documentation

◆ calculate_next_probe_size()

◆ complete_search()

◆ current_mtu()

◆ disable()

◆ enable()

◆ handle_black_hole()

◆ is_enabled()

◆ is_search_complete()

◆ max_mtu()

◆ min_mtu()

◆ next_timeout()

◆ on_packet_too_big()

◆ on_probe_acked()

◆ on_probe_lost()

◆ on_probe_sent()

◆ on_timeout()

◆ probe_size()

◆ reset()

◆ should_probe()

◆ start_search()

◆ state()

Member Data Documentation

◆ config_

◆ consecutive_failures_

◆ current_mtu_

◆ kBlackHoleThreshold

◆ last_probe_time_

◆ probe_count_

◆ probe_in_flight_

◆ probing_mtu_

◆ search_complete_time_

◆ search_high_

◆ search_low_

◆ state_