User Manual

Frame Reception

In essence, the frame reception is the same in both operations of half duplex and full duplex, except that full-duplex operation uses two buffers to transmit and receive the frame independently. The receiving node always “listens” if there is traffic running over the medium when it is not receiving a frame. When a frame destined for the target device comes, the receiver of the target device begins receiving the bit stream, and looks for the PRE (Preamble) pattern and Start-of- Frame Delimiter (SFD) that indicates the next bit is the starting point of the MAC frame until all bit of the frame is received.

For a received frame, the MAC will check:

If it is less than one slotTime in length, i.e. short packet, and if yes, it will be discarded by MAC because, by definition, the valid frame must be longer than the slotTime. If the length of the frame is less than one slotTime, it means there may be a collision happened somewhere or an interface malfunctioned in the LAN. When detecting the case, the MAC drops the packet and goes back to the ready state.

If the DA of the received frame exactly matches the physical address that the receiving MAC owns or the multicast address designated to recognize. If not, discards it and the MAC passe s the frame to its client and goes back to the ready state.

If the frame is too long. If yes, throws it away and reports frameTooLong.

If the FCS of the received frame is valid. If not, for 10M and 100M Ethernet, discards the frame. For Gigabit Ethernet or higher speed Ethernet, MAC has to check one more field, i.e. extra bit field, if FCS is invalid. If there is any extra bits existed, which must meet the specification of IEEE802.3. When both FCS and extra bits are valid, the received frame will be accepted, otherwise discards the received frame and reports frameCheckError if no extra bits appended or alignmentError if extra bits appended.

If the length/type is valid. If not, discards the packet and reports lengthError.

If all five procedures above are ok, then the MAC treats the frame as good and de-assembles the frame.

Publication date: January, 2005

Revision A1

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Edimax Technology ES-516G+ user manual Publication date January Revision A1

ES-516G+ specifications

Edimax Technology has carved a niche for itself in the realm of networking devices, and one of its standout products is the Edimax ES-516G+. This 16-port Ethernet switch is designed to meet the demanding needs of small to medium-sized businesses and network enthusiasts.

At the core of the ES-516G+ is its capacity to support 10/100/1000 Mbps speeds across its 16 ports, enabling efficient data transmission and minimal latency for connected devices. This switch is a Layer 2 unmanaged switch, which simplifies the user experience by eliminating the need for complex configurations. Users can plug in their devices and start functioning immediately, making it an ideal option for those who may not have extensive networking knowledge.

One of the key features of the Edimax ES-516G+ is its support for Auto-MDI/MDI-X, which automatically detects the type of connection required for each port, whether it’s connecting to another switch or end devices like computers and printers. This eliminates the hassle of crossover cables and ensures seamless connectivity.

Moreover, the ES-516G+ incorporates advanced energy-saving technologies that are designed to minimize power consumption without compromising performance. This feature is particularly appealing for environmentally-conscious businesses looking to reduce their carbon footprint. It includes capabilities such as energy-efficient Ethernet (EEE), which adjusts power usage based on the link status and length of connected cables.

The switch features a compact metal housing, providing durability and a professional look suitable for any office environment. It also supports a fanless design for quiet operation, making it an excellent addition to workplaces where noise levels need to be kept to a minimum.

In terms of performance, the Edimax ES-516G+ employs store-and-forward switching technology, which helps to minimize errors by ensuring that only error-free packets are forwarded. This significantly enhances network performance and reliability.

Overall, the Edimax Technology ES-516G+ stands out as a robust, efficient, and user-friendly solution for enhancing network performance in small to medium-sized businesses. Its combination of speed, plug-and-play convenience, energy-saving features, and reliability makes it a compelling choice for users seeking to expand their network capabilities. Whether for a bustling office or a home network, the ES-516G+ is engineered to deliver a seamless, high-performance networking experience.