1-4 CHAPTER 1: INTRODUCTION
Features and
Functions
The hub can be mounted in a 19-inch standard rack or placed on a
flat surface. It supports the 1000 Mbps media access control (MAC)
as specified in the IEEE 802.3z standard. In addition, the hub has
these features:
■ LED indicators report the status of each port and of hub operations. A
meter shows the percentage of bandwidth being used within the hub.
■ The serial console interface allows limited options for port
configuration and, if necessary, firmware updates.
■ Power-on self-test (POST) diagnostics determine whether the hub is
functioning properly at power up.
■ Frame-aging firmware improves performance by minimizing
unnecessary frame aging and subsequent attempts to retransmit
packets at the protocol level.
■ Round-robin arbitration grants fair access for all ports to the hub’s
internal bus on a packet-by-packet basis.
■ Signal retiming restores the timing and amplitude of the received
signal before retransmitting the signal.
■ A carrier integrity monitor checks packets for invalid framing and
removes invalid frames from the network.
■ Jabber control inhibits overly long transmissions of data generated by
the hardware failure of an attached device.
