Switching technology, Vlan (virtual local area network), Power over ethernet (poe) – NetComm NP2500 User Manual

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NP2500 24-Port 10/100 PoE + 2-Port 10/100/1000 WebSMART Switch User Guide

YML842 Rev1

Switching Technology

technology. A switch bridges Ethernet packets at the MAC address level of the Ethernet protocol transmitting
among connected Ethernet or Fast Ethernet LAN segments.

Switching is a cost-effective way of increasing the total network capacity available to users on a local area
network. A switch increases capacity and decreases network loading by dividing a local area network into
different segments, which do not compete with each other for network transmission capacity.

The switch acts as a high-speed selective bridge between the individual segments. The switch, without inter-
fering with any other segments, automatically forwards traffic that needs to go from one segment to another.
By doing this the total network capacity is multiplied, while still maintaining the same network cabling and
adapter cards.

Switching LAN technology is a marked improvement over the previous generation of network bridges, which
were characterized by higher latencies. Routers have also been used to segment local area networks, but the
cost of a router, the setup and maintenance required make routers relatively impractical. Today switches are
an ideal solution to most kinds of local area network congestion problems.

VLAN (Virtual Local Area Network)

A VLAN is a group of end-stations that are not constrained by their physical location and can communicate
as if a common broadcast domain, a LAN. The primary utility of using VLAN is to reduce latency and need for
routers, using faster switching instead. Other VLAN utility includes:

Security, Security is increased with the reduction of opportunity in eavesdropping on a broadcast network
because data will be switched to only those confidential users within the VLAN.

Cost Reduction, VLANs can be used to create multiple broadcast domains, thus eliminating the need of
expensive routers.

Port-based (or port-group) VLAN is the common method of implementing a VLAN, and is the one supplied in
the Switch.

Power over Ethernet (PoE)

Power over Ethernet (PoE) integrates power and data onto one single cabling infrastructure, eliminating the
need to have AC power available at all locations.

Power and Data are integrated onto the same cable. Supporting category 5/5e up to 100 Meters, PoE will
provide power to PoE compatible device, such as IP telephones, wireless LAN access points, and IP security

PoE is already widely adopted in the market, saving up to 50% of overall installation costs by eliminating the
need to install separate electrical wiring and power outlets.