PLANET GSW-1402S - Manual (Page 26)

22
5 Switch Operation
5.1 Address Table
The Switch is implemented with an address table. This address table composed of
many entries. Each entry is used to store the address information of some node in
network, including MAC address, port no, etc. This information comes from the
learning process of Switch.
5.2 Learning
When one packet comes in from any port, the Switch will record the source address,
port no. and the other related information in address table. This information will be
used to decide either forwarding or filtering for future packets.
5.3 Forwarding & Filtering
When one packet comes from some port of the Switching, it will also check the
destination address besides the source address learning. The Switching will lookup
the address-table for the destination address. If not found, this packet will be
forwarded to all the other ports except the port which this packet comes in. And
these ports will transmit this packet to the network it connected. If found, and the
destination address is located at different port from this packet comes in, the
Switching will forward this packet to the port where this destination address is
located according to the information from address table. But, if the destination
address is located at the same port with this packet comes in, then this packet will
be filtered. Thereby increasing the network throughput and availability.
5.4 Store-and-Forward
Store-and-Forward is one type of packet-forwarding techniques. A Store-and
Forward Switching stores the incoming frame in an internal buffer, do the complete
error checking before transmission. Therefore, no error packets occurrence, it is the
best choice when a network needs efficiency and stability.
The 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. GSW-14-2S can be easily configured in any Gigabit network
environment to significantly boost bandwidth using conventional cabling and
adapters.
Due to the learning function of the 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 filter packets whose destination address is on
the same segment as the source address. This confines network traffic 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.
5.5 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