DDS_RtpsReliableReaderProtocol_t Struct Reference
[Extended Qos Support]

Qos related to reliable reader protocol defined in RTPS. More...

List of all members.

Public Attributes
struct DDS_Duration_t	min_heartbeat_response_delay
	The minimum delay to respond to a heartbeat.
struct DDS_Duration_t	max_heartbeat_response_delay
	The maximum delay to respond to a heartbeat.
struct DDS_Duration_t	heartbeat_suppression_duration
	The duration a reader ignores consecutively received heartbeats.
struct DDS_Duration_t	nack_period
	The period at which to send NACKs.
DDS_Long	receive_window_size
	The number of received out-of-order samples a reader can keep at a time.
struct DDS_Duration_t	round_trip_time
	The duration from sending a NACK to receiving a repair of a sample.

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Detailed Description

Qos related to reliable reader protocol defined in RTPS.

It is used to config reliable reader according to RTPS protocol.

Properties:

RxO = N/A
Changeable = NO

QoS:

DDS_DataReaderProtocolQosPolicy DDS_DiscoveryConfigQosPolicy

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Member Data Documentation

struct DDS_Duration_t DDS_RtpsReliableReaderProtocol_t::min_heartbeat_response_delay [read]

The minimum delay to respond to a heartbeat.

When a reliable reader receives a heartbeat from a remote writer and finds out that it needs to send back an ACK/NACK message, the reader can choose to delay a while. This sets the value of the minimum delay.

[default] 0 seconds

[range] [0, 1 year], <= max_heartbeat_response_delay

struct DDS_Duration_t DDS_RtpsReliableReaderProtocol_t::max_heartbeat_response_delay [read]

The maximum delay to respond to a heartbeat.

When a reliable reader receives a heartbeat from a remote writer and finds out that it needs to send back an ACK/NACK message, the reader can choose to delay a while. This sets the value of maximum delay.

[default] The default value depends on the container policy:

For DDS_DiscoveryConfigQosPolicy : 0 seconds
For DDS_DataReaderProtocolQosPolicy : 0.5 seconds

[range] [0, 1 year], >= min_heartbeat_response_delay

struct DDS_Duration_t DDS_RtpsReliableReaderProtocol_t::heartbeat_suppression_duration [read]

The duration a reader ignores consecutively received heartbeats.

When a reliable reader receives consecutive heartbeats within a short duration that will trigger redundant NACKs, the reader may ignore the latter heartbeat(s). This sets the duration during which additionally received heartbeats are suppressed.

[default] 0.0625 seconds

[range] [0, 1 year],

struct DDS_Duration_t DDS_RtpsReliableReaderProtocol_t::nack_period [read]

The period at which to send NACKs.

A reliable reader will send periodic NACKs at this rate when it first matches with a reliable writer. The reader will stop sending NACKs when it has received all available historical data from the writer.

[default] 5 seconds

[range] [1 nanosec, 1 year]

DDS_Long DDS_RtpsReliableReaderProtocol_t::receive_window_size

The number of received out-of-order samples a reader can keep at a time.

A reliable reader stores the out-of-order samples it receives until it can present them to the application in-order. The receive window is the maximum number of out-of-order samples that a reliable reader keeps at a given time. When the receive window is full, subsequently received out-of-order samples are dropped.

[default] 256

[range] [>= 1]

struct DDS_Duration_t DDS_RtpsReliableReaderProtocol_t::round_trip_time [read]

The duration from sending a NACK to receiving a repair of a sample.

This round-trip time is an estimate of the time starting from when the reader sends a NACK for a specific sample to when it receives that sample. For each sample, the reader will not send a subsequent NACK for it until the round-trip time has passed, thus preventing inefficient redundant requests.

[default] 0 seconds

[range] [0 nanosec, 1 year]