Comparison Asus RT-AC58U vs Asus RT-AC87U

The maximum speed provided by the device when communicating wirelessly in the 2.4 GHz band.

This range is used in most modern Wi-Fi standards (see above) - as one of the available or even the only one. The theoretical maximum for it is 600 Mbit. In reality, Wi-Fi at a frequency of 2.4 GHz is used by a large number of client devices, from which congestion of data transmission channels emerges. Also, the number of antennas affects the speed performance of the equipment. It is possible to achieve the speed declared in the specification only in an ideal situation. In practice, it can be noticeably smaller (often by several times), especially with an abundance of wireless technology simultaneously connected to the equipment. The maximum speed at 2.4 GHz is specified in the characteristics of specific models to understand the real capabilities of Wi-Fi equipment. As for the numbers, according to the capabilities in the 2.4 GHz band, modern equipment is conditionally divided into models with speeds up to 500 Mbit inclusive and over 500 Mbit.

The maximum speed supported by the device when communicating wirelessly in the 5 GHz band.

This range is used in Wi-Fi 4, Wi-Fi 6 and Wi-Fi 6E as one of the available bands, in Wi-Fi 5 as the only one (see "Wi-Fi Standards"). The maximum speed is specified in the specifications in order to indicate the real capabilities of specific equipment - they can be noticeably more modest than the general capabilities of the standard. Also, in fact, it all depends on the generation of Wi-Fi. For example, devices with Wi-Fi 5 support can theoretically deliver up to 6928 Mbit (using eight antennas), with Wi-Fi 6 support up to 9607 Mbit (using the same eight spatial streams). The maximum possible communication speed is achieved under certain conditions, and not every model of Wi-Fi equipment fully satisfies them. Specific figures are conditionally divided into several groups: the value up to 500 Mbit is rather modest, many devices support speeds in the range of 500 - 1000 Mbit, indicators of 1 - 2 Gbps can be attributed to the average, and the most advanced models in class provide a data exchange rate of over 2 Gbps.

The number of USB 2.0 ports provided in the design of the device.

USB in this case plays the role of a universal interface for connecting peripheral devices to the router. The specific USB devices supported and how they are used may vary. Examples include working with a flash drive that plays the role of a drive for working in FTP or file server mode (see "Functions / Capabilities"), connecting to a printer in print server mode(see ibid), connecting a 3G modem (See "Data input (WAN-port)"), etc.

Specifically, USB 2.0 allows you to transfer data at speeds up to 480 Mbps. This is noticeably less than that of more advanced standards (starting with USB 3.2 gen1 described below), and the power supply of such connectors is low. However, even such characteristics are often quite enough, taking into account the specifics of the use of Wi-Fi devices. In addition, peripherals for newer versions can also be connected to the USB 2.0 port — the main thing is that the power supply is enough. Therefore, although this standard is considered obsolete, it is still widely used in modern wireless equipment. There are even models that provide 2 or even more USB 2.0 ports; this allows you to simultaneously use several external devices at once — for example, a 3G modem and a USB flash drive.

The presence of a removable antenna(or several antennas) in the design of the device.

Only external antennas can be made removable (see "Type of antennas"). This design is especially convenient for storage and transportation: it allows you to remove external equipment, making the device less bulky. In addition, many devices with this feature allow replacement of standard antennas with others (for example, more powerful ones or with a more optimal radiation pattern). Some of these models are even initially sold without antennas — in the expectation that the user will choose them himself, at his discretion; such equipment is not needed for domestic use, but it can be very convenient when selecting high-quality professional equipment. On the other hand, the detachable design reduces the reliability of the antenna mounting, increases the possibility of failures at the connection point, and increases the cost of the device. Therefore, most modern Wi-Fi equipment is still equipped with fixed antennas.

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".

The total number of antennas in the router that are responsible for communication in the 2.4 GHz band. For details about the number of antennas, see "Total antennas", about the range — "Frequency range".

The total number of antennas in the router that are responsible for communication in the 5 GHz band. For details about the number of antennas, see "Total antennas", about the range — "Frequency range".

The total number of antennas in the router that can operate on both 5 GHz and 2.4 GHz frequencies. For details about the number of antennas, see "Total antennas", about the range — "Frequency range".

Rated power of the Wi-Fi transmitter used in the device. If multiple bands are supported (see “Ranges of operation”) the power for different frequencies may be different, for such cases the maximum value is indicated here.

The total transmitting power provided by the device directly depends on this parameter. This power can be calculated by adding the transmitter power and the antenna gain (see above): for example, a 20 dBm transmitter coupled with a 5 dBi antenna results in a total power of 25 dBm (in the main antenna coverage area). For simple domestic use (for example, buying a router in a small apartment), such details are not required, but in the professional field it often becomes necessary to use wireless devices of a strictly defined power. Detailed recommendations on this matter for different situations can be found in special sources, but here we note that the total value of 26 dBm or more allows the device to be classified as equipment with a powerful transmitter. At the same time, such capabilities are not always required in fact: excessive power can create a lot of interference both for surrounding devices and for the transmitter itself (especially in urban and other similar conditions), as well as degrade the quality of the connection with low-power electronics. And for effective communication over a long distance, both the equipment itself and external devices must have the appropriate power (which is far from alway...s achievable). So, when choosing, you should not chase the maximum number of decibels, but take into account the recommendations for a particular case; in addition, a Wi-Fi amplifier or MESH system often turns out to be a good alternative to a powerful transmitter.