Gigabyte System Network

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Features

  • Payload bandwidth: up to 800MB per second full-duplex (typical application experience is 790MB per second): faster than Fibre Channel, ATM OC12, Gigabit Ethernet, and HIPPI
  • Latency: adapter latency of 4 microseconds; MPI latency of 13 microseconds
  • Interoperability: IP over GSN, ST over GSN, BDS over GSN, and ARP over GSN
  • OS Bypass library: Libst over GSN
  • First adapter with a parallel protocol stack-not just multithreaded
  • Excellent price/performance
GSN is an ANSI standard networking technology that delivers the highest network performance while maintaining compatibility with HIPPI, Ethernet, and other standard networks. GSN delivers superior bandwidth (800MB per second) and low latency for the most demanding applications, and is suitable as a backbone for aggregating traffic from multiple gigabit-per-second networks.

GSN Moves Big Data Efficiently

GSN is the highest bandwidth interconnect standard, providing full-duplex 6400Mb-per-second (800MB-per-second in each direction) error-free, flow-controlled data transmission. GSN is ideal wherever organizations require timely and efficient movement of large amounts of information, including scientific and technical computing, HDTV, data mining, transaction processing, video and film archiving, and storage management. It is the only standard networking technology capable of providing the bandwidth necessary for the film and video industry's migration to digital studios and HDTV. Customers with large data warehouses can use the technology for ultrahigh-performance file servers and backup servers capable of moving terabytes of data per hour. SGI has been the leading proponent of GSN technology and was the first system vendor to introduce GSN products. The SGI GSN adapter offers partial- and full-bandwidth implementations of this standard in single and dual XIO slot versions.

GSN Software Features

GSN uses four multiplexed channels called the virtual channels. These virtual channels are allocated to control traffic, low-latency traffic, and bulk traffic to avoid the issues when attempting to mix both bulk and small interactive traffic. Software overhead is greatly reduced through a reliable link in hardware, along with multiplexing, retransmission, and flow control. GSN provides reliable, flow-controlled links to eliminate network congestion. Flow control is the foundation for operating system bypass, the ability to move data between the link and the application without the need for time-consuming system calls or other intervention. Unlike earlier HIPPI standards, GSN allows multiplexing to ensure that one application is not shut out from the network while another is performing a large data transfer.

GSN Adapter Features

The SGI GSN adapter for the SGI 2000 series, the SGI Origin 3000 series, Silicon Graphics Onyx2, and the SGI Onyx 3000 series is a single-port network interface board that conforms to the ANSI HIPPI-6400-PH specification, revision 2.1. The adapter implements 20-bit parallel copper-based GSN, providing bandwidth of 800MB per second in each direction. This is in excess of eight times the speed of HIPPI-800 and Fibre Channel, six times the speed of Gigabit Ethernet, and four times the speed of OC48c ATM. A maximum payload of 2.5TB per hour can be moved in each direction.

Protocol and Programming Support

  • IP over GSN driver that interfaces the GSN hardware to the Internet Protocol (IP) and its associated transport-layer protocols: TCP, UDP, ICMP, etc.
  • ST over GSN driver that interfaces the GSN hardware to the ST Protocol
  • ARP for GSN that automatically resolves physical-layer HIPPI-6400 ULA addresses to/from network-layer addresses (for IP and ST)
  • Support for static table lookup to handle systems that do not support ARP
  • IRIX socket-based application programming interface (API) to the IP network stack (driver) for use by customers who want to develop or port applications to send/receive data through the IP over GSN subsystem
  • IRIX socket-based API to the ST network stack (driver) for use by customers who want to develop or port applications to send/receive data through the ST over GSN subsystem
  • Libst over GSN library implementing ST OS Bypass for use by customers who want to develop applications which require maximum scalability and a very thin layer between the application and the hardware only
  • MPI over GSN library for use by customers who want to port or develop MPI applications over GSN
  • Full broadcast support