Gigabit Passive Ethernet Network Concept - MikroTik GPEN and netPowerLite 7R

Latvian company SIA Mikrotīkls, more widely known as MikroTik, has launched a number of well-received networking and wireless devices. These specialists in broadband devices also proposed solutions in the field of GPEN, or Gigabit Passive Ethernet Network, aimed at the introduction of cheap and efficient Ethernet networks that are a simple extension of the network - GPON installations. The range of devices we tested included:

Below you will find detailed information about these network devices, how they work, and possible applications. You will also learn the results of testing various PoE power supplies that could work as power sources MikroTik netPower Lite 7R in your target GPEN network implementation.

MikroTik's GPEN, or Gigabit Passive Ethernet Network series of devices is intended to replace or complement GPON installations with cheaper and simpler Ethernet-based devices. Minimizing costs, but not the speed - this is the basic assumption of GPEN. Among these devices one can find:

It is also possible to include GigabitEthernet client devices into the network infrastructure.

MikroTik netPower Lite 7R - CSS610-1Gi-7R-2S OUT

MikroTik netPower Lite 7R switch with the product code CSS610-1Gi-7R-2S OUT is closed in a rugged, IP54 class, sealed housing. It allows for external mounting on the wall, creating simple and aesthetic box with relatively small dimensions 304 mm x 212 mm x 71 mm. The device has CE, EAC, ROHS certification. The physical interfaces available on the netPower Lite 7R are:

All ports are located under a solid flap that can be opened, where there is enough space for laying cables. For the switch no power supply is included. You have to buy it separately. However, the set includes mounting accessories - a set of screws and two metal rims. netPower Lite 7R provides three alternative ways of power supply, among which worth mentioning are up to 7 GE ports with PoE-in. The option of taking power from the clients connected to the switch allows for simpler installation of the device, without the need to provide classic mains power. It is also possible to build backup power supply system from many points.

NetPower Lite 7R has a non-blocking bandwidth of 28 Gbps. Its theoretical packet switching capacity can be as high as 56 Gbps, while the transfer rate is 41.7 Mpps. Such capabilities are due to the installed SwitchOS system in combination with passively cooled high-performance components, which are not specified by the manufacturer. The management of the device is possible at the layer-2 level of the network.

GPEN11 and GPEN21 PoE injectors - power proposals for NetPowerLite 7R

GPEN11 GigabitEthernet PoE injector is a simple module that allows you to power compatible devices, including the NetPower Lite 7R, via Ethernet. The minimalist, sealed 92mm x 104mm x 24mm enclosure with an option to mount it on a wall has two Gigabit LAN ports and a power input.

GPEN21 terminal is, according to the manufacturer's description, an intelligent PoE injector with advanced software-controlled repeater functions. It can supply power to the devices via PoE, but also ensures management thanks to dedicated software. The device itself can also be powered via PoE-IN in IEEE 802.3af/at standard. Thus, the small casing hides 2 Gigabit Ethernet 10/100/1000 Mbps ports as well as SFP slot and a DC power input. Software-wise the GPEN21 allows:

Like the netPower Lite 7R kit GPEN21 does not include a power supply but only the elements for mounting it on a wall or in a telecommunication cabinet. The supported supply voltage range is 12 - 57 V.

Before using MikroTik managed devices, it is recommended to perform a software update when available. Factory preinstalled software may not provide full functionality and the manufacturer is constantly working on developing management systems. The latest versions are available at the official MikroTik website, and the information can also be found on company forums.

The manufacturer suggests powering the netPower Lite 7R switches via client points for easier installation site selection and a simpler network infrastructure. The GPEN11 and GPEN21 modules can work here, although they require the purchase of additional power supplies, which increases costs. A separate power supply operating within the range of 12-57 V, and the best recommended 48 V, together with a PoE injector, will cost about 70-100 PLN per one point. It should be noted that power supplies below 28-30W are not recommended for installations that use PoE OUT port to power another device.

An additional issue is that the typical most popular 48 V power supply has a current of 0.3-0.5 A, which may not be sufficient to power the entire MikroTik netPowerLite 7R GPEN installation, especially supporting another device via the PoE-out port. The switch itself, with three LAN ports and two SFP inserts used, requires 0.31 A at 25 V, as can be observed on the measuring device. Using all ports, a current of just under 0.4 A would be required.

A week-long experiment showed that the MikroTik netPower Lite 7R switch can be powered without concern by other power sources than the MikroTik GPEN11 or GPEN21. In our lab tests, we tested several popular power supplies that, due to their design, also allow for elegant wall mounting, just like the GPEN11 or GPEN21, and may cost significantly less. You will find a summary of the tests in the table below:

PoE Injector Ubiquiti U-POE-AF
Compatibility - OK
Remarks: reports a problem with cable pairs

2nd PoE power supply Ubiquiti POE-24-24W-G
Compatibility - OK
Notes: -

3. the Ubiquiti POE-24-30W PoE power supply
Compatibility - NO
Notes: -

4. the Ubiquiti POE-50-60W PoE Power Supply
Compatibility - NO
Notes: -

5. MikroTik GPOE 48V power supply
Compatibility - OK
Remarks: reports a problem with cable pairs

It is worth noting that despite the similarity of the equipment, different models of power supplies work with MikroTik netPower 15FR and others with netPower Lite 7R. In the tests the switch worked properly when powered with different compatible power supplies, even of different voltages. No abnormalities were observed when the current power supply failed and automatically switched to the next one. There is no packet loss and transmission speeds remain unchanged at maximum saturation of the Ethernet port. Therefore, it can be said that the equipment allows to provide multiple sources of emergency power, which guarantees high resistance to power problems. At any given moment, the MikroTik netPower 7R switch uses the power supply with the highest voltage, while the others show low current consumption, remaining in standby mode.

Network implementations using GPEN solutions can be varied, depending on the conditions at the device deployment site. Examples are shown in the following diagrams

MikroTik GPEN concept and a number of devices created directly for its implementation seems to be a simple, relatively cheap and efficient solution for ISPs. A truncated version of the netPower device, i.e. MikroTik netPower Lite 7R switch, has a low price, but only features 8 Gigabit Ethernet ports, which may not be sufficient in many places. The limitation may also be the type of the device, and consequently - the SwitchOS software, not RouterOS, although probably thanks to that it can be purchased at a more affordable price.

The list of advantages of MikroTik's netPower Lite 7R includes a number of details that make it convenient to use. These include robust housing resistant to external factors, possibility of mounting it on a wall or mast with the included accessories, and a template for making holes for cables which can be routed in a way chosen to suit the place of installation. Another plus is the option of using power supplies other than the dedicated modules, which does not limit the system or network to MikroTik devices only. High-performance equipment works in many topologies and has the potential to change the approach to building infrastructure for local ISP services.