Comparison D-Link DIR-815/AC vs D-Link DIR-825/AC/G1

The WAN port characterizes the ability of the device to receive a wired signal. There may be models with both one port and two WAN ports, and in rare cases, more connected providers. Such an expanded number of WAN connectors affects the cost and, accordingly, is found in more part among professional-level routers.

In terms of speed, when choosing a device, the priority is the speed of the output LAN port or Wi-Fi. However, faster WAN ports ( 1 Gbps, 2.5 Gbps, 5 Gbps, 10 Gbps) allow you to divide the load on several outputs at once without reducing speed performance, as may be the case with WAN port 100 Mbps.

In this case, LAN means standard network connectors (known as RJ-45) designed for wired connection of LAN devices — PCs, servers, additional access points, etc. The number of ports corresponds to the number of devices that can be directly connected to wired equipment. way.

In terms of speed, 100 Mbps (Fast Ethernet) and 1 Gbps (Gigabit Ethernet) are the most popular options today. At the same time, thanks to the development of technology, more and more gigabit devices are being produced, although in fact this speed is critical only when transferring large amounts of information. At the same time, some models, in addition to the standard speed of the main LAN ports, may have a 2.5 Gbps, 5 Gbps and even 10 Gbps LAN port with increased bandwidth.

Gain provided by each device antenna; if the design provides for antennas with different characteristics (a typical example is both external and internal antennas), then the information, usually, is indicated by the highest value.

Amplification of the signal in this case is provided by narrowing the radiation pattern — just as in flashlights with adjustable beam width, reducing this width increases the illumination range. The simplest omnidirectional antennas narrow the signal mainly in the vertical plane, "flattening" the coverage area so that it looks like a horizontal disk. In turn, directional antennas (mainly in specialized access points, see "Device type") create a narrow beam that covers a very small area, but provides a very solid gain.

Specifically, the gain describes how powerful the signal is in the main direction of the antenna compared to an perfect antenna that spreads the signal evenly in all directions. Together with the power of the transmitter (see below), this determines the total power of the equipment and, accordingly, the efficiency and range of communication. Actually, to determine the total power, it is enough to add the gain in dBi to the transmitter power in dBm; dBi and dBm in this case can be considered as the same units (decibels).

In general, such data is rarely required by the average user, but it can be useful in some specific situations that specialists have to deal with. Detailed calculation methods for suc...h situations can be found in special sources; here we emphasize that it does not always make sense to pursue a high antenna gain. First, as discussed above, this comes at the cost of narrowing the scope, which can be inconvenient; secondly, too strong a signal is also often undesirable, for more details see "Transmitter power".