Comparison NETGEAR AC815S vs NETGEAR AC791L

Wi-Fi connection speeds, more precisely, Wi-Fi standards supported by a modem with the appropriate capabilities (see "Type", "Connection").

— Wi-Fi 3 (802.11g). A further development of the Wi-Fi 1 (802.11b) standard, developed primarily for increasing connection bandwidth (2.4 GHz) and introduced in 2003. 802.11g hardware is fully backwards compatible with 802.11b, so even the simplest of today's Wi-Fi devices support both of these standards.

— Wi-Fi 4 (802.11n). The Wi-Fi standard, which is a further development of the formats described above — in particular, by supplementing them with support of MIMO technology (distribution of input and output between several antennas). Introduced in 2009. The main operating frequency is 2.4 GHz, but there are devices supplemented with a 5 GHz band.

— Wi-Fi 5 (802.11ac). Built on top of 802.11n, introduced late 2013. The main improvements were the increase in the number of streams at the second frequency (5 GHz) and the introduction of more advanced MIMO and modulation standards, which increased the throughput accordingly.

The greatest distance at which the modem's built-in router is capable of providing communication via the Wi-Fi interface (see "Connection").

It should be taken into account that in fact the range strongly depends on a number of factors that are not related to the main specs of the modem: the presence of interference and obstacles in the signal path, the specs of the Wi-Fi module of the connected device, the battery charge in this device or the modem itself, etc. Therefore, the actual range indicators can be noticeably lower than the claimed ones: for example, when working through a wall, they are noticeably reduced. However, this spec quite clearly describes the overall range of the device, and comparisons of different models on it are quite acceptable.

Also note that it does not always make sense to purchase a device with a maximum range — although a long range provides additional convenience, it requires high transmitter power, which significantly increases the size and price of the modem. Therefore, when choosing, it is worth proceeding primarily from the intended scenarios of use. For example, if you need a 3G connection to access the Internet on the road from your tablet, a range of several metres will be enough. But for installation in a large private house, it makes sense to look for a model with increased effective range.

The 4G (LTE) mobile connection speed supported by the modem.

All modern LTE equipment is assigned one or another category (Cat.3, Cat.4, Cat.6, Cat.7, Cat.9, Cat.12, Cat.13, Cat.16, Cat.18, Cat.19, Cat.20, Cat.22), on which the transmission speed directly depends. This paragraph specifies both this category and specific speed indicators, moreover, in two parameters — for reception and for transmission. The transmission speed is always much lower, but given the specifics of mobile Internet access, this is usually not critical.

Note that equipment with different speed categories will be quite compatible with each other, however, the throughput will be limited by the capabilities of the slower device. It is also worth saying that this paragraph indicates the theoretical maximum; practical amounts can be noticeably lower (depending on the quality of the network coverage and the features of specific electronics). However, a modem with a higher speed category will perform faster in fact.

The maximum operating time of the modem with battery power (see "Power") on a single charge in Internet browsing mode. Such power is typical for Wi-Fi routers, therefore, usually, Internet browsing is supposed to provide access to the World Wide Web for an external Wi-Fi device.

This spec is the main indicator of battery life for any battery-powered modem, because it describes the time of using it for its main purpose without recharging. At the same time, you should know that this indicator is measured under certain "perfect" conditions; the actual operating time depends on a number of factors, including the intensity of browsing, the amount of data transferred, the number of connected devices and the distance to them, the cellular network signal strength, etc. Therefore, in fact, the battery life of the modem may be somewhat lower. Nevertheless, it is quite possible to compare different models with each other according to the operating time stated in the specs.

The maximum time the modem can operate on battery power (see "Power") in standby mode on a single battery charge.

This mode can be described as the standby mode. It assumes that the device is turned on, its operating circuits are powered and ready to respond to an incoming signal or user command at any time, but no data exchange occurs and no features work. This indicator is not as important as the Internet browsing time (see above), but it is also of practical importance and allows you to evaluate the battery life of the device — after all, during breaks between communication sessions, the modem is in standby mode.

Possibility of modem performing in power bank mode. This mode allows you to use the built-in battery to power your smartphone or other external gadget. Thus, the modem can be an additional external battery, which is important in situations where it is not possible to charge a portable device.