
sometimes moves quickly to the CPU when servers are upgraded to incorporate LANStreamer technology.
Of course, other components can emerge as the bottleneck as throughput increases. The wire (network bandwidth) itself can become a bottleneck if throughput requirements overwhelm the ability of the network technology being used. For example, if an application requires 3 MBps of throughput, then a
For more discussion of hardware performance tuning, please see 5.1, ªHardware Tuningº on page 167.
The LANStreamer technology is used in the IBM Auto LANStreamer Adapters for PCI and MCA as well as the EtherStreamer and Dual EtherStreamer MC 32 LAN adapters.
Note
The EtherStreamer LAN adapter supports full duplex mode, which allows the adapter to transmit as well as receive at the same time. This provides an effective throughput of 20 Mbps (10 Mbps on the receive channel and 10 Mbps on the transmit channel). To implement this feature, an external switching unit is required.
1.7.3 PeerMaster Technology
The PeerMaster technology takes LAN adapters one step forward by incorporating an
If more than one card is installed, packets can be switched both intra- and
The IBM Quad PeerMaster Adapter is a
It ships with 1MB of memory. Each port on an adapter serves a separate Ethernet segment. Up to six of these adapters can reside on a single server and up to 24 segments can be defined in a single server.
This adapter can also be used to create virtual networks (VNETs). Using VNETs, the NOS sees multiple adapter ports as a single network, eliminating the need to implement the traditional router function either internal or external to the file server.
The Ethernet Quad PeerMaster Adapter is particularly appropriate when there is a need for:
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Switching/Bridging traffic among multiple Ethernet segments Attaching more than eight Ethernet
Chapter 1. IBM PC Server Technologies 33