Switch Operation; Address Table; Learning; Forwarding & Filtering - Planet Networking & Communication FGSD-1008HPS User Manual

User's Manual of FGSW-Series

7. SWITCH OPERATION

7.1 Address Table

The Managed PoE+ Switch is implemented with an address table. This address table is 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 Managed PoE+ Switch.

7.2 Learning

When one packet comes in from any port, the Managed PoE+ Switch will record the source address, port no., and the other
related information in the address table. This information will be used to decide either forwarding or filtering for future packets.
7.3 Forwarding & Filtering
When one packet comes from some port of the Managed PoE+ Switch, it will also check the destination address besides the
source address learning. The Managed PoE+ Switch 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 Managed PoE+ Switch 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.

7.4 Store-and-Forward

Store-and-Forward is one type of packet-forwarding techniques. A Store-and-Forward Managed PoE+ Switch stores the
incoming frame in an internal buffer, and does the complete error checking before transmission. Therefore, no error will occur.
Choosing a network that needs efficiency and stability is the best choice.
The Managed PoE+ 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
the existing hubs, which nearly always improves the overall performance. An Ethernet Switching can be easily configured in any
Ethernet network environment to significantly boost bandwidth using conventional cabling and adapters.
Due to the learning function of the Managed PoE+ Switch, 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 and
reduce the overall load on the network.
The Managed PoE+ Switch performs "Store and Fforward"; therefore, no error packets occur. More reliably, it reduces the
re-transmission rate. No packet loss will occur.
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