Comparison MikroTik CRS328-24P-4S+RM vs MikroTik CRS125-24G-1S-IN

The form factor determines how the switch is installed.

— Desktop. Devices designed to be placed on a flat surface such as a countertop or shelf; some models also allow hanging on the wall. Significantly easier to install than rack or DIN rail equipment (see below), but most desktop switches are entry-level, maximum mid-range. This is because desktop placement is less secure than rack or rail mounting, making it less suitable for professional equipment.

— Rack mounted. Switches designed for installation in a telecommunications rack. To do this, the design provides for an appropriate set of fasteners, and the body is made in a standard size. This size is quite large, which allows for numerous network ports; and the rack mounting itself is reliable. Therefore, this option is used by most professional-level switches, although there are also relatively simple models with this installation method.

— Mounted on a DIN rail. Switches mounted on a standard DIN rail. Such rails are used as mounting fixtures, in particular, on electrical panels and in cabinets for special equipment, however, if desired, they can be fixed to any vertical surface, including a regular wall. Specifically, "switches" with a similar installation, as well as rack-mounted ones, are mainly of a professional level; however, rail-mounted models are much smaller, resulting...in more modest functionality and fewer ports. Also note that they are usually executed in a vertical rather than a horizontal layout.

— Street (on the mast). Switches that can be installed outdoors. A characteristic feature of such equipment is the enhanced protection of the case, which protects the internal components from dust, moisture, high and low temperatures, etc. winter application (if you need a frost-resistant model, you can use the "Operating temperature" list below). However, if the equipment needs to be placed on the street (or in a room where the conditions are not very different from the street ones), then it is definitely worth choosing from this category.

The bandwidth of a switch is the maximum amount of traffic that it can handle. Specified in gigabits per second.

This parameter directly depends on the number of network ports in the device (excluding Uplink). Actually, even if the bandwidth is not given in the specifications, it can still be calculated using the following formula: the number of ports multiplied by the bandwidth of an individual port and multiplied by two (since both incoming and outgoing traffic are taken into account). For example, a model with 8 Gigabit Ethernet connectors and 2 SFP ports will have a bandwidth of (8*1 + 2*1)*2 = 20 Gbps.

The choice for this indicator is quite obvious: you need to evaluate the expected traffic volumes in the serviced network segment and make sure that the switch's bandwidth will cover it with a margin of at least 10-15% (this will give an additional guarantee in case of emergency situations). At the same time, if you plan to often work at high, close to maximum, loads, it will not hurt to clarify such a characteristic as the internal bandwidth of the switch. It is usually given in a detailed technical description, and if this value is less than the total throughput, serious problems may arise under significant loads.

The maximum number of MAC addresses that can be stored in the Switch's memory at the same time. Specified in thousands, for example, 8K — 8K.

Recall that the MAC address is the unique address of each individual network device used in physical routing (at layer 2 of the OSI network model). Switches of all types work with such addresses. And it is worth choosing a switch according to the size of the table, taking into account the maximum number of devices that are supposed to be used with it (including based on the possible expansion of the network). If the table is not enough, the switch will overwrite new addresses over the old ones, which can noticeably slow down the work.

The number of optical network ports of the SFP standard provided in the design of the switch. We emphasize that we are talking about "ordinary" SFPs; SFP+ data is usually listed separately.

Specifically, in switches, the marking “SFP” usually means a connector for fiber with a connection speed of 1 Gbps. Technically, this is not much compared to RJ-45 speeds; however, this connection format has a number of advantages. One of the main ones is a greater effective range: the mentioned gigabit standard used in switches works with a cable length of up to 550 m, and by the standards of fiber, this is still very little. True, the cable itself is sensitive to kinks and requires quite delicate handling; on the other hand, it is completely immune to electromagnetic interference. On the other hand, in general, the SFP format is noticeably less popular in network equipment than RJ-45; therefore, there are few ports of this type even in advanced devices. So, solutions for 2 or 4 SFP connectors are most widely used, although there are more - 6, 8, or even 10 or more. It is also worth considering that the so-called combo connectors can be used in switches, combining SFP and RJ-45; the presence of such ports is specified in the notes, they are taken into account both in the calculation of RJ-45 and in the calculation of SFP.

To clarify, Uplink inputs also often use this type of connector; however,...their number is specified separately (see below).

The number of optical SFP+ ports provided in the design of the switch. Let's clarify right away that we are talking about ordinary network ports; Uplink inputs can also use this interface, however their number is specified separately even in this case (see below).

The general advantages of optical fiber over conventional Ethernet cable are longer communication range and insensitivity to electromagnetic interference. Specifically, SFP+ is a development of the original SFP standard; in switches, such connectors typically operate at a speed of 10 Gbps. As for the number of such ports, for all its advantages, fiber optics in network equipment is still used quite rarely. Therefore, the most common switches are 1 - 2, less often 4 SFP + connectors, although there are more. It is also worth considering that the so-called combo connectors can be used in switches, combining SFP + and RJ-45; the presence of such ports is specified in the notes, they are taken into account both in the calculation of RJ-45 and in the calculation of SFP+.

The number of Uplink connectors provided in the design of the switch.

“Uplink” in this case is not a type, but a connector specialization: this is the name of the network interface through which the switch (and network devices connected to it) communicate with external networks (including the Internet) or network segments. In other words, this is a kind of "gate" through which all traffic from the network segment served by the switch is transmitted further. Uplink, in particular, can be used to connect to a similar "switch" (for horizontal network expansion) or to a higher level device (like a core switch).

Accordingly, the number of Uplink connectors is the maximum number of external connections that the switch can provide without using additional equipment. The specific type of such a connector may be different, but this is usually one of the varieties of LAN or SFP; see "Uplink type" for details.

The type of connector(s) used as the Uplink interface on the switch.

For more information about such an interface, see above; Here we note that the same network ports are usually used as Uplink as for connecting individual devices to the switch. Here are the main options for such connectors:

— Fast Ethernet — LAN network connector (for twisted pair cables) supporting speeds up to 100 Mbit/s. This speed is considered low by modern standards, while the Uplink port places increased demands on throughput - after all, traffic from all devices served by the switch passes through it. Therefore, in this role, Fast Ethernet ports are used mainly in inexpensive and outdated models.

— Gigabit Ethernet — LAN connector supporting speeds up to 1 Gbit/s. This speed is often sufficient even for a fairly extensive network, while the connectors themselves are relatively inexpensive.

— 2.5 Gigabit Ethernet — LAN connector supporting speeds up to 2.5 Gbit/s.

— 10Gigabit Ethernet — LAN connector supporting speeds up to 10 Gbit/s. Such features allow you to work comfortably even with very large volumes of traffic, but they significantly affect the price of the switch. Therefore, this option is rare, mainly in high-end models.

— SFP. A connector for a fiber optic cable that supports speeds of about 1 Gbit/s. At the same time, over Gigabit Ethernet, which has a similar throughput, this connector has one noticeable advantage - a...longer connection range (usually up to 550 m).

- SFP+. Development of the SFP standard described above. Switches usually provide a connection speed of 10 Gbit/s; like the original standard, it noticeably exceeds the effective range of an Ethernet connection. On the other hand, the real need for such speeds does not arise so often, and SFP+ is quite expensive. Therefore, the presence of such Uplink connectors is typical mainly for high-end models with a large number of ports.

- SFP28. Another development of SFP with increased throughput up to 25 Gbit/s.

- QSFP / QSFP+. The fastest SFPs up to 40 Gbit/s.

Note also that the connectors described above (except perhaps Fast Ethernet) are rarely used as the only type of Uplink input. Combinations of electrical and fiber optic ports—SFP/Gigabit Ethernet and SFP+/10Gigabit Ethernet—have become noticeably more widespread. This provides versatility in connection, allowing you to use the most convenient type of cable in a given situation; and if necessary, of course, you can use all Uplink inputs at once. However, it is worth considering that in some models, Ethernet and SFP interfaces can be combined in one physical connector. So before purchasing, it doesn’t hurt to clarify this nuance separately.

There are also switches that use a combination of two types of SFP - SFP/SFP+; however, there are few such models and they are mainly of the professional level.

This feature allows you to supply power over the Ethernet cable to the switch itself. This reduces the number of wires and simplifies power supply, which is especially convenient if the device is installed in a hard-to-reach place where there is no outlet nearby, and it is difficult to pull an additional cable.

The switch supports the Power over Ethernet function.

This feature allows the switch to supply power to network devices over the same Ethernet cable that transmits data. This reduces the number of wires and simplifies power supply, which is especially convenient if the device is installed in a hard-to-reach place where there is no outlet nearby, and it is difficult to pull an additional cable. An example is an IP surveillance camera installed under the ceiling.

The number of PoE outputs may vary. It should also be borne in mind that when several consumers are connected at the same time, specific power restrictions apply; see "Total PoE Power" for details.

Accordingly, such devices are much more expensive than switches without PoE.