Comparison Zyxel NBG6615 vs Zyxel NBG6604

Methods for connecting to the Internet (or other external network, such as in bridge mode) supported by the device.

The classic, most common version of such a connection nowadays is LAN (Ethernet), but this is not limited to this. A wired connection can also be made via ADSL or SFP fiber, and wirelessly via mobile networks (using a SIM card, SIM card 5G or an external modem for 3G or 4G), as well as via Wi-Fi. Here is a more detailed description of each option:

— Ethernet (RJ45). Classic wired connection via a network cable via an RJ-45 connector. Also known as "LAN", although this designation is not entirely correct. Nowadays, it is one of the most common methods of wired Internet connection, and is also widely used in local networks. This is due to the fact that the speed of Ethernet is actually limited only by the capabilities of network controllers; at the same time, even the simplest modules support up to 100 Mbps, and in advanced equipment this value can reach 10 Gbps.

— ADSL. A technology primarily used for wired Internet connections over existing landline telephone lines. This is its main advantage — you can use ready-made lines without fiddling w...ith laying numerous additional wires; at the same time, ADSL works independently of telephone calls and does not interfere with them. At the same time, the speed of such a connection is noticeably lower than via Ethernet — even in advanced equipment it does not exceed 24 Mbps. In addition, ADSL traffic is distributed asymmetrically: full speed is achieved only when working for reception, data transmission speed is much lower, which creates problems for video communication and some other tasks. So nowadays, ADSL is gradually being replaced by more advanced standards, although the complete disappearance of this technology is still far away.

— Wi-Fi. Connect to an external data source via Wi-Fi. By definition, this format of operation is used by Wi-Fi adapters (see "Device type"), as well as by most MESH equipment. (However, if the MESH system package includes both nodes and the main control device for them, then the WAN input can be specified for the control device, and often this is not Wi-Fi). Also, this type of data input can be provided in other types of equipment — in particular, routers and access points (for example, to work in bridge or repeater mode).

— 3G modem (USB). Internet connection via 3G mobile network using a separate external modem connected to the USB port. Most often, we are talking about UMTS networks (the development of GSM mobile communications), the most common in Europe and the post-Soviet space; however, it may also be possible to use modems for CDMA networks (EV-DO technology). These nuances, as well as compatibility with specific modem models, need to be clarified separately. However, anyway, 3G may be a good option for situations where a wired Internet connection is difficult or impossible, such as in the private sector. In addition, some Wi-Fi devices with this feature are equipped with autonomous power supplies and can even be used on the go. The data transfer speed of 3G is close to broadband wired connection (from 2 to 70 Mbps with a normal signal, depending on the specific technology); however, it is less than in 4G networks (see below), but 3G coverage is more extensive, and equipment for this standard is cheaper.

— 4G (LTE) modem (USB). Internet connection via 4G mobile network (LTE) using a separate external modem connected to the USB port. The main features are similar to the 3G connection described above, adjusted for the fact that in this case more advanced fourth-generation networks are used. The data transfer rate in such networks reaches about 150 Mbps; they are not as widespread as 3G-connection, but soon we can expect a change in the situation. In addition, it should be noted that in Europe and the post-Soviet space, LTE networks are usually deployed on the basis of 3G UMTS and GSM networks; so in the absence of full-fledged 4G coverage, modems for such networks can work according to the 3G and even GSM standard.

— SIM card. Connecting to the Internet via a mobile network using a mobile operator's SIM card installed directly in the device. The specific type of supported networks depends both on the capabilities of the router and on the conditions of a particular mobile operator; however, all such equipment is compatible with at least 3G networks, and often 4G as well. The features of these networks are described in detail above (you can also read about the advantages of a mobile Internet connection there). This option is convenient because it allows you to do without a separate USB modem — you just need to purchase a SIM card, the cost of which is negligible. In addition, the use of "sim cards" has a positive effect on compactness and ease of carrying. On the other hand, the built-in mobile communication module significantly affects the overall cost — and you will have to pay for it anyway (whereas a model with support for external modems does not have to be bought immediately with a modem, such devices usually allow wired connection). Therefore, you should pay attention to this option if you initially plan to connect to the Internet through mobile networks.

- SIM card (5G). The ability to operate Wi-Fi equipment in high-speed 5G mobile networks with a peak bandwidth of up to 20 Gbps for reception and up to 10 Gbps for data transmission. Implemented via a SIM card with appropriate 5G support. This standard reduces power consumption compared to previous versions, and it also uses a number of complex solutions aimed at improving the reliability and overall quality of communication - in particular, multi-element antenna arrays (Massive MIMO) and beamforming technologies (Beamforming).

— SFP (optics). Connection via fiber optic cable of the SFP standard. Such a connection can be carried out at high speeds (measured in gigabytes per second), and the fiber, unlike the Ethernet cable, is practically insensitive to external interference. On the other hand, the support of this standard is not cheap, and its capabilities are unnecessary for domestic use. Therefore, SFP is found mainly in professional-level Wi-Fi devices.

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.

Device support for MU-MIMO technology - multi-user multi-threaded I / O.

Communication in multiple streams is implemented through the use of multiple antennas on both the transmitting and receiving device. This allows you to increase the bandwidth of the channel, as well as improve the overall quality and stability of the connection. And the term "multi-user" usually means that Wi-Fi equipment is able to simultaneously work with several external devices that support multi-streaming (MIMO). The only exceptions are Wi-Fi adapters (see "Device type") - they are more about the ability to interact with the router / access point as efficiently as possible, which also uses MU-MIMO.

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".

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 al...ways 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.

The main functions and capabilities implemented in the device.

This category mainly includes the most key functions — namely load balancing (Dual WAN), channel reservation, Link Aggregation, Bluetooth(various versions, including Bluetooth v 5), voice assistant, NAT, MESH modes, bridge, repeater, Beamforming function , firewall (Firewall) and CLI (Telnet). Here is a more detailed description of each of these items:

— Dual WAN. Possibility of simultaneous connection to two external networks. Most often used for simultaneous work with two Internet connections (although other options are possible); at the same time, there are two main modes of operation with such connections — redundancy (Failover / Failback) and balancing (Load Balance). So, in backup mode, the device constantly uses the main channel to connect to the Internet, and in case of failures on this channel, it automatically switches to a fallback option. In balancing mode, both channels are used simultaneously, while the load between them is distributed either a...utomatically (depending on the traffic consumption of a particular device) or manually (clearly specified in the settings for specific devices). This allows, for example, to separate the channel for online games from the rest of the connection, minimizing lags and increasing efficiency.

— Link Aggregation. A function that allows you to combine several parallel physical communication channels into one logical one — to increase the speed and reliability of the connection. Simply put, with Link Aggregation, a device can be connected to another device not with one cable, but with two or even more at once. The increase in speed in this case occurs due to the summation of the throughput of all physical channels; however, the total speed may be less than the sum of the speeds — on the other hand, combining several relatively slow connectors is often cheaper than using equipment with a more advanced single interface. And the increase in reliability is carried out, firstly, by distributing the total load over individual physical channels, and secondly, by means of "hot" redundancy: the failure of one port or cable can reduce the speed, but does not lead to a complete disconnection, and when the channel is restored, the channel is switched on automatically.

— Bluetooth. The device supports Bluetooth wireless technology. The meaning of this function will depend on the format of the equipment operation (see "Device type"). For example, adapters with this capability allow you to supplement your PC not only with Wi-Fi, but also with Bluetooth support — thanks to this, you can get by with one adapter instead of two. And in routers and access points, this feature allows external devices to access the Internet (or local area network) over a Bluetooth connection instead of Wi-Fi. This format of work allows you to unload the Wi-Fi channel and reduce the power consumption of connected devices; this is especially important for smart home components and other IoT devices, some routers/access points expressly state that Bluetooth is intended mainly for such electronics. Other ways of using this technology, more specific, may be envisaged; however, this is rare.

— Voice assistant. Device support for a particular voice assistant. The most common options are (individually or together):

• Amazon Alexa
• Google Assistant

The specific functionality of these assistants can be clarified from special sources (especially since it is constantly being optimized and expanded). Here we note that in the case of Wi-Fi equipment, we are usually not talking about an assistant built into the device itself, but about improved compatibility with smartphones and other gadgets that have the corresponding assistant installed. Such functionality can be especially useful given that modern voice assistants are also used to control smart home components. Communication with such control is often carried out just through a home router or other similar equipment, and the support of such equipment for voice assistants greatly simplifies setup and expands the capabilities of the entire system.

— NAT (Network Address Translation). A function that allows Wi-Fi equipment, when working with an external network (for example, the Internet), to replace the IP addresses of all computers and other devices connected to this equipment with one common IP address. In other words, a network with such a router is seen "from the outside" as one device, with one common IP. The most popular use of NAT is to connect several subscribers to the Internet (for example, all computers and gadgets within a home or office) through one provider account. At the same time, the number of such subscribers within the network is limited only by the capabilities of the router and can be freely changed; this will not affect access to the World Wide Web (whereas without using NAT, one would have to organize a separate account for each device). NAT support is a mandatory feature for routers (see "Device type").

— Bridge mode. Possibility of operation of the equipment in the bridge mode. This mode allows you to wirelessly connect individual network segments to each other — for example, to combine two floors if it is difficult to lay a cable between them. However, communication over longer distances is also possible — in some directional access points (see "Device type"), created mainly for just such an application, the range can exceed 20 km. Actually, this mode supports most access points (both directional and conventional), but it is also popular in other types of equipment, in particular, routers.
Note that to work in bridge mode, it is best to use the same type of device — this guarantees high-quality communication in both directions. It is also worth mentioning that in addition to the two-way point-to-point mode, there is also equipment with support for multi-way bridges (“point-to-multipoint”); the availability of such a possibility should be clarified separately.

— Repeater mode. An operating mode in which the equipment only repeats the Wi-Fi signal from another device, playing the role of a repeater. The main function of this function is to expand Wi-Fi networks, providing access where the main device (for example, a router) does not reach. A classic example of repeaters is Wi-Fi amplifiers (see "Device type"), they have this mode by definition; however, it is also found in other types of Wi-Fi equipment. The exception is MESH systems that have similar specifics, but differ in the format of work. See below for more information about this format, but here we note that networks with repeaters are in many ways inferior to MESH in terms of practical capabilities. Firstly, the signals from the main equipment and from the repeater are seen as separate Wi-Fi networks, and when moving between them, subscriber devices must reconnect; this can happen automatically, but disconnections and network changes still cause inconvenience. Secondly, working through a repeater significantly reduces the speed of Wi-Fi. Thirdly, the repeater operates according to a strictly fixed, pre-established routing scheme. On the other hand, access points with a repeater function are much cheaper than MESH nodes, and the mentioned drawbacks are far from always critical.

— MESH mode. Ability to operate the device as a MESH network node. By definition, all MESH systems have this feature, but it can be provided in other types of equipment. A detailed description of networks of this type is given in the paragraph “Device type — MESH system”. Here we will briefly describe their features and the difference between this mode and the repeater mode (see above), which has a largely similar purpose.
MESH technology allows you to create a single wireless network using many separate nodes (access points) connected to each other via Wi-Fi. In this case, the so-called seamless mode of operation is implemented: the entire network is seen as a single whole, switching between access points, if necessary, occurs automatically, in such cases the connection is not broken and the user does not notice the transition to another network node at all. This is one of the key differences from using repeaters. Another difference is dynamic routing: MESH network nodes automatically determine the optimal signal traversal mode. Due to this, as well as due to some other features of this technology, the presence of "intermediaries" on the signal path practically does not affect the communication speed (unlike the same repeaters). The main disadvantage of equipment with this function can be called a relatively high cost.

— Beamforming. A technology that allows you to amplify the Wi-Fi signal in the direction where the receiving device is located (instead of broadcasting this signal in all directions or in a wide sector, as is the case in normal mode). Narrowing the radiation pattern allows you to send more power towards the receiver, thus increasing the range and communication efficiency; while the position of the receiving device is determined automatically, the user does not need to deal with additional settings. And many models of Wi-Fi equipment are capable of amplifying the signal in several directions at once (usually, several antennas are provided for this). At the same time, subscriber devices do not have to support Beamforming — communication improvement is noticeable even with the one-way use of this technology (although not as obvious as with the two-way one).
Also note that the unified Beamforming standards were officially implemented as part of the Wi-Fi 5 specification. However “beamforming” was also used in earlier versions of Wi-Fi, however, different manufacturers used different methods for implementing Beamforming, incompatible with each other. So these days, this feature is almost never found outside of Wi-Fi 5 compatible equipment.

— Firewall. A feature that allows a Wi-Fi device to control traffic passing through it. In fact, the Firewall is a set of software filters: these filters compare data packets with the specified parameters and decide whether or not to pass traffic. In this case, the processing can be carried out according to two rules: “everything that is not expressly prohibited is allowed”, or vice versa, “everything that is not expressly permitted is prohibited”. The main function of a firewall is to protect the network (or individual network segments) from unauthorized access and various attacks. In addition, this function can be used to control user activity — for example, prohibitions on access to certain Internet sites. Note that a firewall can also be implemented at the level of individual devices, but using it on a router allows you to secure the entire network at once.

CLI (Telnet). Ability to control the device via Telnet protocol. This is one of the protocols used today to remotely control network equipment; while Telnet, unlike another popular HTTP standard, does not have a graphical interface and uses only the command line. Such access is used mainly for service purposes — for debugging and changing settings in other text-based protocols (HTTP on web pages, SMTP and POP3 on mail servers, etc.); Telnet requires specialized knowledge.