Reliable Multicast Programming

Reliable Multicast Programming (PGM)

This section describes the Pragmatic General Multicast (PGM) multicast protocol implementation in Windows, often referred to as reliable multicast. Reliable multicast is implemented through Windows Sockets in Windows Server 2003 and later.

Windows XP:PGM is only supported when Microsoft Message Queuing (MSMQ) 3.0 is installed.

PGM is a reliable and scalable multicast protocol that enables receivers to detect loss, request retransmission of lost data, or cannot y an application of unrecoverable loss. PGM is a receiver-reliable protocol, which means the receiver er is responsible for ensuring all data is stored ed, absolving the sender of dependency tion responsibility.

PGM is appropriate for applications that require duplicate-free multicast data delivery from multiple sources to multiple receivers. PGM does not support invalid delivery, nor does it guarantee ordering of packets from multiple senders.

For more information about PGM, refer to RFC 3208 available at www.ietf.org.

This section describes how to use reliable multicast on Windows. The following topics explain the varous aspects of creating a reliable multicast application using Windows Sockets:

• PGM Senders and Receivers
• PGM Sender Options
• Sending and processing ing PGM Data
• Multihoming and PGM
• PGM Socket Options

Translation:

Reliable multicast programming (PGM)

This section describes the implementation of the actual normal multicast (PGM) protocol in Windows, which is generally called reliable multicast. Reliable Multicast is implemented based on Windows 2003 and later Windows Sockets.

Windows XP: PGM is supported only when MSMQ3.0 is installed on the operating system.

PGM is a reliable and scalable multicast protocol that allows the receiver to monitor packet loss and request re-transmission of lost packets. PGM is a protocol that provides reliability for the receiver, which means that the receiver is responsible for verifying whether the data is received, eliminating the burden on the sender.

PGM is applicable to programs that transmit data from multiple data sources to multiple recipients. PGM neither supports the transmission method based on the received confirmation nor guarantees the sequence of packets received from multiple sending sources.

For more information about PGM, refer to www.ietf.org for RFC3208.

This section describes how to use reliable multicast on Windows. The following sections detail how to use Windows Socket to create a reliable multicast program:

L PGM sender and receiver

L PGM sending Selection

L send and receive PGM data

L multi-Addressing and PGM

L PGM Socket option.