Enterasys Networks 6H302-48 - Manual (Page 19)

Connectivity
Introduction 1-3
1.1 CONNECTIVITY
The module connects to Ethernet networks or workstations through the front panel connectors. The
ports support Unshielded Twisted Pair (UTP) cables with an impedance between 85 and 111 ohms
at lengths up to 100 meters. The ports are IEEE 802.3 10BASE-T and 100BASE-TX compliant.
1.2 RUNTIME IP ADDRESS DISCOVERY
This feature enables the module to automatically accept an IP address from a Boot Strap Protocol
(BootP) server on the network without requiring a user to enter an IP address through Local
Management.
When the module is connected to the network and powered up, Runtime IP Address Discovery
(RAD) checks the module for an IP address. If one has not yet been assigned (module IP address
set to 0.0.0.0), RAD checks to see if any of the module interfaces have a link. If a link is
discovered, RAD sends out Reverse Address Resolution Protocol (RARP) and BootP requests to
obtain an IP address from a BootP server on the network.
The RAD requests start at an interval of one per second. The interval then doubles after every
transmission until an interval of 300 seconds is reached. At this point, the interval remains at 300
seconds. The RAD requests continue until an IP address is received from a RARP or BootP server,
or an IP address is entered using Local Management.
1.3 HALF-DUPLEX/FULL-DUPLEX AUTO-NEGOTIATION
The fixed front panel ports on the module have the ability to auto-negotiate the ports’ mode of
operation (half-duplex or full-duplex) between two devices according to IEEE 802.3 standards.
During Auto-Negotiation, two devices automatically exchange information “telling” each other
their current operating mode. The Auto-Negotiation feature targets the maximum capability that
can be reached between the two devices. For example, the module can adjust to full-duplex
operation when the device on the other end of the connection can also adjust from half-duplex to
full-duplex. If the device on the other end of the connection can only operate in half-duplex mode,
then the module simply adjusts to operate in half-duplex mode.
1.4 SMARTTRUNK
Traditional 802.1D Spanning Tree Bridges only allow one active data path between any two
switches; all other parallel data paths are in Standby or Blocking mode. If one interface or path
should fail, then the other interface automatically comes out of Blocking mode and forwards all of
the traffic. This is fine for redundancy purposes. However, it is not the most efficient use of
resources.
NOTE: The module will reboot after RAD is successful.