GateD Open Shortest Path First (OSPF)

The Green Hills GateD^® Fast OSPF (Open Shortest Path First) module is one of Green Hills Software’s flagship routing products and sets the standard for the industry. Designed from the ground up, GateD OSPF includes all of the expected functionality, passes all of the industry test suites (including ANVL and the UNH suites at the University of New Hampshire) and has seen great success in deployment.

The GateD Fast OSPF implementation is fully compliant with OSPF version 2, RFC 2328. It supports both Type 1 and Type 2 external routes, multiple areas, area border router functionality, and virtual links. Additionally, it operates over broadcast, point-to-point, point-to-multipoint, and NBMA networks.

Beyond full support for the base RFC, this cutting edge implementation has all of the features commonly requested by router vendors and their customers. This includes both standards based features – such as opaque LSAs, not-so-stubby areas, and traffic engineering capabilities—as well as a number of proprietary, compile-time options.

While the largest networks in the world use IS-IS as their Internet Gateway Protocol (IGP), the vast majority of carriers use OSPF. OSPF was designed to be the link-state routing protocol of choice for IP routing. Its simplicity of configuration combined with resiliency and scalability through features such as multiple area support and virtual links, make it suitable for a wide variety of network sizes and topologies.

Today, more and more enterprise networks are converting to OSPF. Large networks, such as those deployed by campuses, government agencies, and major corporations, cannot get by with just RIP any longer. OSPF is becoming a requirement for the enterprise router and the LAN switching environment.

Finally, like the other GateD IGPs, Fast OSPF is well suited to act as the underlying routing function for advanced multicast applications using the PIM protocol.

Speed
Speed—The Green Hills Fast OSPF, like IS-IS, has been highly optimized with patent pending enhancements to improve the speed of the shortest path tree (SPF). The implementation of the SPF is fast and operates on speed-optimized data structures. Tests have shown one second convergence times for networks approaching 10,000 nodes (almost a full order of magnitude bigger than the largest OSPF networks in the world today).

Elegance
Fast OSPF was designed from the ground up to be highly extensible and modularized. As a result, the code path is exceptionally clear and readable. Further, functionality is neatly divided among the products’ “c” and “h” files. As a result, when new functionality has appeared, such as the addition of opaque LSAs or traffic engineering extensions, the modifications to the code have been exceptionally clear, along with the points of interaction between source modules.

Traffic Engineering and CSPF
One of the most recent additions to the Fast OSPF module is support for traffic engineering extensions. The code includes not only the latest extensions specified by the IETF, but also a proprietary constraint-based SPF calculation to make use of the data passed around by these extensions. A straightforward API gives outside applications direct accessibility to both the data and the calculation of constrained paths.

Better bottom line
For certain applications, such as voice-over-IP, millisecond timer granularity is a requirement. But even in a classical IP setting, Green Hills MULTI compile-time options let customers choose footprint and speed optimizations that result in substantial bottom-line savings, by reducing memory requirements and processing power at any given point in time. And by using Green Hills Software's complete routing and switching bundles that are pretested and validated together, customers achieve maximum time to market benefits while increasing system reliability and availability.

Reduced on-going support costs
Over time, the Internet has grown, increasing the demand for new features, and the specifications have been revised to add support for those new features. But once a router box is deployed in the field, there’s a strong resistance to changing working code. The elegance and distribution of Green Hills’ Fast OSPF implementation make the tough decisions easier. As new features are delivered, the points of interaction are exceptionally clear, dramatically reducing the load on a QA department before releasing the code. In addition, protocols are thoroughly tested and validated with Green Hills’ INTEGRITY operating system and GHNet routing stack, providing customers integrated solutions enabling significant reductions in the time and cost to add to or update existing deployed systems.

GateD’s platform independent scalable software has been ported, tested and validated on Green Hills secure INTEGRITY operating system and GHNet IPv4/v6 router stack, providing end customers with a complete, functional single-vendor solution.

For pre-integrated reference platform or commercial platform support or operating system support other than INTEGRITY, please contact Green Hills (gated-info@ghs.com).

• RIP
• RIPng
• IS-IS
• BGP
• OSPF3
• MP-BGP Extensions for IPv6
• MP-BGP for Multicast
• CLI

• VRRP
• PIM-DM
• PIM-SM
• PIM-SSM
• DVMRP
• MSDP
• Layer 2 Switching
• SNMP v1/2c/3

• INTEGRITY Operating System
• INTEGRITY Secure Virtualization
• GHNet IPv4/v6 host and routing stack
• SSH, SSL/TLS, IPSec/IKE, crypto algorithms
• Telnet, RADIUS, SNTP, DNS, DHCP
• Wireless Supplicant with security and CCX