Black Box LE14XXA manual 4.0OPERATION, 4.1Switching Functionality, Filtering and Forwarding

Models: LE14XXA Modular Switches

1 51
Download 51 pages 50.35 Kb
Page 37
Image 37

Black Box Modular Switches

Installation and User Guide (8/99)

4.0OPERATION

This chapter describes the functions and operation of the LE14XXA-Series.

4.1Switching Functionality

ALE14XXA-Series provides switched connectivity at Ethernet wire-speed among al of its ports. The LE14XXA-Series supports10/100Mbs for copper media and 10 or 100Mb separate traffic domain for fiber port to maximize bandwidth utilization and network performance. All ports can communicate to all other ports in a LE14XXA-Series, but local traffic on a port will not consume any of the bandwidth on any other port.

LE14XXA-Series units are plug-and-play devices. There is no software configuring t be done at installation or for maintenance. The only hardware configuration settings are user options for UP-LINK on RJ-45 4-port. Half / Full duplex mode and 10 or 100Mbps selection f the switched ports can be done through jumper settings inside the unit. The internal functions o both are described below.

Filtering and Forwarding

Each time a packet arrives on one of the switched ports, the decision is taken to eithe filter or to forward the packet. Packets whose source and destination addresses are on the same port segment will be filtered, constraining them to one port and relieving the rest of the network from processing them. A packet whose destination address is on another port segment will be forwarded to the appropriate port, and will not be sent to the other ports where it is not needed Traffic needed for maintaining the operation of the network (such as occasional multi-cast packets) are forwarded to all ports.

The LE14XXA-Series Switches operate in the store-and-forward switching mode, which eliminates bad packets and enables peak performance to be achieved when there is heavy traffic on the network.

Address Learning

All 16-port LE14XXA-Series units have address table capacity of 24K node addresse (12K for 8-port models), suitable for use in large networks. They are self-learning, so that as

31

Page 37
Image 37
Black Box LE14XXA, Modular Switches 4.0OPERATION, 4.1Switching Functionality, Filtering and Forwarding, Address Learning