IBM 9077 manual Conclusion

2.7 Conclusion

The SP Switch Router 9077-04S has an aggregate bandwidth of 800 MB/s. An SP wide node by contrast is capable of no more than about 65 MB/s of sustained throughput. A wide node’s CPU hits a wall at about 5000 packets/second, whereas the 9077 is capable of an aggregate of 2.8 million packets/second. All this is achieved in part because of the non-blocking crosspoint switch with four 100 MB/s, full duplex connection points. This enables multiple paths to operate at full speed simultaneously.

Unlike the SP nodes, the SP Switch Router is designed with high availability in mind. It provides balanced, fully redundant power supplies that can be hot swapped in case of failure. It provides the ability for redundant paths to an SP Switch to be configured on a single 9077; with dynamic routing protocols, a second 9077 can be used to provide a backup path in case of system failure of the primary router. In either case, each media card is hot swappable and autoconfigured after the initial install has been completed.

With its high port count on interfaces such as FDDI and Ethernet and its highly scalable performance, the SP Switch Router provides a very cost effective solution. With each media card you get a nearly linear scaling of performance with very little cost increase. An SP node by comparison runs out of CPU cycles and/or slots very quickly requiring the purchase of another entire node.

Since the 9077 (or rather the Ascend GRF) was originally designed for ISP’s, it has a full set of protocols, including dynamic routing protocols such as OSPF, BGP4 and RIPv2. It also has the memory required to hold up to 150,000 routes and the speed to access a table of this size without performance degradation. Support for media types not supported by the SP nodes also enables the SP to now be connected into networks that will be important for its future. These include support for HSSI and Sonet, which are important for the SP’s ever-growing role as a Web server or online transaction manager.

66IBM 9077 SP Switch Router: Get Connected to the SP Switch