24-port NWay Ethernet Switch User’s Guide

♦Link Change Event This trap is sent whenever the link of a port changes from link up to link down or from link down to link up.

♦Port Partition This trap is sent whenever a port is partitioned as a result of more than sixty-one collisions on the port (i.e., it is automatically partitioned). The number of collisions that triggers this trap is the same at either 10Mbps or 100Mbps.

♦Broadcast Storm This trap is sent whenever the port reaches the broadcast storm rising or falling threshold.

♦Address Table Full This trap is sent whenever the MAC Address Table is full.

♦Entity MIB Change This trap is sent whenever a MIB object of Entity MIB version 2 (RFC 2737) is changed.

MIBs

Management information and counters are stored in the Switch in the Management Information Base (MIB). The Switch uses the standard MIB-II Management Information Base module. Consequently, values for MIB objects can be retrieved from any SNMP-based network manager software. In addition to the standard MIB-II, the Switch also supports its own proprietary enterprise MIB as an extended Management Information Base. These MIBs may also be retrieved by specifying the MIB’s Object-Identity (OID) at the network manager. MIB values can be either read-only or read-write.

Read-only MIBs variables can be either constants that are programmed into the Switch, or variables that change while the Switch is in operation. Examples of read-only constants are the number of ports and types of ports. Examples of read-only variables are the statistics counters such as the number of errors that have occurred, or how many kilobytes of data have been received and forwarded through a port.

Read-write MIBs are variables usually related to user-customized configurations. Examples of these are the Switch’s IP Address, Spanning Tree Algorithm parameters, and port status.

If you use a third-party vendors’ SNMP software to manage the Switch, a diskette listing the Switch’s propriety enterprise MIBs can be obtained by request. If your software provides functions to browse or modify MIBs, you can also get the MIB values and change them (if the MIBs’ attributes permit the write operation). This process however can be quite involved, since you must know the MIB OIDs and retrieve them one by one.

Packet Forwarding

The Switch learns the network configuration and uses this information to forward packets. This reduces the traffic congestion on the network, because packets, instead of being transmitted to all segments, are transmitted to the destination only. Example: if Port 1 receives a packet destined for a station on Port 2, the Switch transmits that packet through Port 2 only, and transmits nothing through the other ports.

Aging Time

The Aging Time is a parameter that affects the auto-learn process of the Switch in terms of the network configuration. Dynamic Entries, which make up the auto-learned-node address, are aged out of the address table according to the Aging Time that you set.

The Aging Time can be from 10 seconds to 1000000 seconds. A very long Aging Time can result with the out-of-date Dynamic Entries that may cause incorrect packet filtering/forwarding decisions.

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Switch Management Concepts

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D-Link DES-3225G manual MIBs, Packet Forwarding, Aging Time
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DES-3225G specifications

The D-Link DES-3225GF and DES-3225G are both robust Ethernet switches designed to meet the networking needs of small to medium-sized enterprises and organizations. These devices are part of D-Link's comprehensive range of unmanaged layer 2 switches, known for their reliability and ease of use.

The DES-3225GF features a total of 25 Ethernet ports, including 24 10/100Base-TX ports and 1 Gigabit SFP slot, while the DES-3225G also comes with 25 ports but includes 24 10/100/1000 Mbps copper ports. Both models support Auto-MDI/MDI-X for seamless connection setup without the need for crossover cables, simplifying the deployment process.

One of the standout features of these switches is their wire-speed performance that enables high-speed data transfers and efficient traffic management. Each port is designed to provide non-blocking switching, which ensures that the bandwidth is fully utilized without any packet loss. The switches support IEEE 802.3x flow control, which helps to manage data flow and prevent overflow during heavy traffic periods.

The DES-3225GF and DES-3225G offer users a simple yet efficient way to expand their network. With a plug-and-play design, they require minimal configuration, allowing for quick integration into existing network infrastructures. These switches are equipped with a durable chassis, ensuring they can withstand the rigors of a busy IT environment.

Both models boast energy-efficient technologies that comply with IEEE 802.3az, which helps in reducing power consumption during periods of inactivity. By detecting link status and adjusting power accordingly, these switches contribute to a more sustainable networking solution.

In terms of form factor, the DES-3225GF and DES-3225G are rack-mounted, making them suitable for integration into standard network cabinets. This design ensures that the devices can be efficiently managed alongside other network equipment.

For management and security, the switches support features such as VLAN tagging and port security, allowing network administrators to segment traffic and protect the network from unauthorized access. With their sturdy build, innovative features, and straightforward implementation, the D-Link DES-3225GF and DES-3225G are ideal choices for organizations looking to enhance their network performance while keeping costs manageable.
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