25 lines
1.3 KiB
Text
25 lines
1.3 KiB
Text
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OpenPGM is an open source implementation of the Pragmatic General
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Multicast (PGM) specification in RFC 3208 available at www.ietf.org.
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PGM is a reliable and scalable multicast protocol that enables
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receivers to detect loss, request retransmission of lost data, or
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notify an application of unrecoverable loss. PGM is a
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receiver-reliable protocol, which means the receiver is responsible
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for ensuring all data is received, absolving the sender of reception
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responsibility. PGM runs over a best effort datagram service,
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currently OpenPGM uses IP multicast but could be implemented above
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switched fabrics such as InfiniBand.
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PGM is appropriate for applications that require duplicate-free
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multicast data delivery from multiple sources to multiple receivers.
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PGM does not support acknowledged delivery, nor does it guarantee
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ordering of packets from multiple senders.
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PGM is primarly used on internal networks to help integrate disparate
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systems through a common communication platform. A lack of IPv4
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multicast-enabled infrastructure leads to limited capability for
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internet applications, IPv6 promotes multicast to be a part of the
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core functionality of IP but may still be disabled on core routers.
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Support of Source-Specific Multicast (SSM) allows for improved WAN
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deployment by allowing end-point router filtering of unwanted source
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traffic.
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