Internal Hub - NEC Electra Elite IPK II System User Manual

Electra Elite IPK II
Description
A network switch is a computer networking device that connects network segments. It uses the logic of a
network bridge but allows a physical and logical star topology. The switch determines how and to which
port the data is forwarded, based on layer 2 MAC addresses. It is often used to replace network hubs. A
switch is also often called an intelligent hub.
Switches, unlike hubs, use microsegmentation to create collision domains, one per connected segment.
This way, only the Ethernet devices which are directly connected via a point-to-point link, or directly
connected hubs are contending for the medium. By eliminating the possibility of collisions, full-duplex
point-to-point connections on the switch become possible.
When multiple ETUs requiring Ethernet data connections are installed in an Electra Elite IPK II KSU, the
HUB ETU can provide a neat and simple installation.
The HUB(8)-U( ) ETU is an in-skin, fast Ethernet switching hub unit that provides the following services:
Basic LAN Settings:
Auto Negotiation

This feature can allow/deny Auto Negotiation for port speed and duplex mode for each port. When
this function is allowed, the HUB(8)-U( ) ETU negotiates with linked equipment to determine the
speed (10Mbps or 100Mbps) and operating duplex mode (Full or Half).
Link Speed Selection

Data switching speed can be manually set to 10Mbps or 100Mbps for each port. This feature is
allowed only when Auto Negotiation is denied.
Duplex Mode Selection

Duplex mode can be manually set to Half Duplex or Full Duplex for each port. This feature is
allowed only when Auto Negotiation function is denied. Currently only Auto Negotiate and Half
Duplex settings are supported on IPK II.
MDI/MDIX Mode Selection

MDI/MDIX mode can be set to MDI, MDIX, or Auto detection. When this mode is set to Auto
detection, the HUB(8)-U( ) ETU can automatically determine whether or not it needs to crossover
between pairs so that an external crossover cable is not required. If Auto Negotiation for port
configuration is not allowed, this Auto MDIX mode must not be used. Only fixed MDI or MDIX
mode can be used.

Internal Hub

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