Planet SW-804 [13/16] Auto negotiation

The Ethernet Switch scans the destination address from the packet-

header, searches the routing table provided for the incoming port

and forwards the packet, only if required. The fast forwarding makes

the switch attractive for connecting servers directly to the network,

thereby increasing throughput and availability. However, the switch is

most commonly used to segment existing hubs, which nearly always

improves overall performance. An Ethernet Switching can be easily

congured in any Ethernet network environment to signicantly boost

bandwidth using conventional cabling and adapters.

Due to the learning function of the Ethernet switching, the source

address and corresponding port number of each incoming and outgoing

packet are stored in a routing table. This information is subsequently

used to lter packets whose destination address is on the same

segment as the source address. This connes the network trafc to its

respective domain, reducing the overall load on the network.

The Switch performs “Store and Forward” therefore, no error packets

occur. More reliably, it reduces the re-transmission rate. No packet loss

will occur.

3.5 Auto-Negotiation

The STP ports on the Switch have built-in “Auto-negotiation”. This

technology automatically sets the best possible bandwidth when a

connection is established with another network device (usually at Power

On or Reset). This is done by detect the modes and speeds at the

second of both device is connected and capable of, both 10Base-T and

100Base-TX devices can connect with the port in either Half- or Full-

Duplex mode.

If attached device is: 100Base-TX port will set to:

• 10Mbps, no auto-negotiation 10Mbps

• 10Mbps, with auto-negotiation 10/20Mbps (10Base-T/Full-Duplex)

• 100Mbps, no auto-negotiation 100Mbps

• 100Mbps, with auto-negotiation

100/200Mbps

(100Base-TX/Full-Duplex)