Installation guide

Glossary
Glossary-6
Power over Ethernet
The IEEE 802.3af standard for providing Power over Ethernet (PoE) capabilities.
When Ethernet is passed over copper cable, two twisted pairs are used for data
transfer, and two twisted pairs are unused. With PoE, power can either be passed
over the two data pairs or over the two spare pairs.
Private VLANs
Private VLANs provide port-based security and isolation between ports within the
assigned VLAN. Data traffic on downlink ports can only be forwarded to, and from,
uplink ports.
QinQ Tunneling
QinQ is designed for service providers carrying traffic for multiple customers across
their networks. It is used to maintain customer-specific VLAN and Layer 2 protocol
configurations even when different customers use the same internal VLAN IDs.
Quality of Service (QoS)
QoS refers to the capability of a network to provide better service to selected traffic
flows using features such as data prioritization, queuing, congestion avoidance and
traffic shaping. These features effectively provide preferential treatment to specific
flows either by raising the priority of one flow or limiting the priority of another flow.
Remote Authentication Dial-in User Service (RADIUS)
RADIUS is a logon authentication protocol that uses software running on a central
server to control access to RADIUS-compliant devices on the network.
Remote Monitoring (RMON)
RMON provides comprehensive network monitoring capabilities. It eliminates the
polling required in standard SNMP, and can set alarms on a variety of traffic
conditions, including specific error types.
Rapid Spanning Tree Protocol (RSTP)
RSTP reduces the convergence time for network topology changes to about 10% of
that required by the older IEEE 802.1D STP standard.
Secure Shell (SSH)
A secure replacement for remote access functions, including Telnet. SSH can
authenticate users with a cryptographic key, and encrypt data connections between
management clients and the switch.
Simple Mail Transfer Protocol (SMTP)
A standard host-to-host mail transport protocol that operates over TCP, port 25.