Good quality cables are the key to reliable data transmission in Ethernet networks

All Keenetic router models have a built-in Ethernet switch with network ports (sockets). The blue '0' port is for connecting the Internet cable from your ISP, and the other ports are for home devices.
A Fast Ethernet switch provides connection speeds of up to 100 Mbit/s for network devices, and a Gigabit Ethernet switch — up to 1000 Mbit/s (1 Gbit/s).


Ethernet cable networks use twisted pair cable as the physical medium for signal transmission. The cables are connected to the network devices using an 8P8C connector (plug).


For a stable and reliable Internet connection, a cable must have the following characteristics:

- A category 5 standard or higher;
- 8-core copper, not copper-coated aluminium based;
- the cable must be properly and firmly crimped (8P8C connectors fitted correctly on both sides of the cable)
- Length must not exceed 100 m;
- no kinks, knots or twists.

These are the standard features that Keenetic routers comply with. The most common cable used today is either 8 core (4-pair) Unshielded Twisted Pair (UTP) or shielded FTP (Foiled Twisted Pair) category 5/5e cable.

If the cable is not up to standard (e.g. due to poor quality cable, connectors or poor crimping), distortion, errors and dropped links can occur in the data path, resulting in poor connection quality and Internet failures.

Depending on the hardware capabilities of the router's built-in switch, cable category and number of wires, the maximum link speed will be 100 Mbps when connected to a router with a Fast Ethernet switch and 1 Gbps when connected to Gigabit Ethernet.

If the link speed is 10 Mbps, this often indicates that there is a problem with the connection. If the computer is not switched off and is not in 'sleep' mode, it most often indicates that there is a problem with the cable. If you connect a Gigabit Ethernet adapter to a Gigabit router, using a Cat. 5 or higher 8-core cable and see a connection speed of 100 Mbps instead of 1 Gbps, it usually indicates a bad network cable as well. You can check the speed in the router's web interface on the 'System dashboard' screen.


Internet cable from an ISP

When you connect your router to the Internet using Ethernet technology, a dedicated Internet cable is used. Usually, the provider himself installs the cable in the room (flat, house) when the customer connects to the Internet. The customer then connects it directly to the PC or to the router (to a special socket that is designed to connect the Internet cable).


If you use a poor-quality cable on the router's WAN port, physical reconnects (link drops) can frequently occur, resulting in Internet failures.

If you notice that the Internet LED globus.png on the router frequently goes off, and there are messages like this in the router's system log:

[I] Jun 18 11:49:36 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link up at port 0 (100FD/AN).
[I] Jun 18 11:54:50 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link down at port 0.
[I] Jun 18 11:55:22 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link up at port 0 (100FD/AN).
[I] Jun 18 11:55:39 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link down at port 0.
[I] Jun 18 11:55:52 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link up at port 0 (100FD/AN).
[I] Jun 18 12:02:12 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link down at port 0.
[I] Jun 18 12:02:14 ndm: Network::Interface::Switch: "FastEthernet0/0": switch link up at port 0 (100FD/AN).

and on a Gigabit router:

[I] Dec 15 09:08:58 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link up.
[I] Dec 15 09:20:46 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link down.
[I] Dec 15 09:20:49 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link up.
[I] Dec 15 09:21:49 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link down.
[I] Dec 15 09:21:51 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link up.
[I] Dec 15 09:49:01 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link down.
[I] Dec 15 09:49:03 ndm: Network::Interface::GigabitEthernet: "GigabitEthernet1": link up.

the first thing to do is to solve the problem with the Internet cable. Most of these errors are related to the quality of the network cable and can be solved by changing the cable or re-crimping it and replacing the connectors. Make sure that the connector of the Internet cable is installed properly. The cable must not hang on the wires in the connector; this leads to poor contact.


If the Internet is not working normally and there is a problem with the link on the router's WAN port, contact your ISP, request a line test with a cable tester and re-crimp the Internet cable. The ISP must provide you with a good quality dedicated cable for your Internet connection. To provide a reliable and stable connection, you must have a cable at least Category 5, be no longer than 100 m in one piece all the way from the ISP's switch to the router and not made up of pieces. The connectors on both ends of the cable must be crimped identically to the standard.

If you see a connection speed of 100 Mbit/s instead of 1 Gbit/s when connecting to a gigabit router after re-crimping the cable, ask your ISP to switch your Internet cable to another port on the switch or to another switch if possible. The problem may be related to a switch port on the ISP side.

If you have a network cable crimping tool, you can crimp and replace the connector on the Internet cable yourself. For more information on this, see 'Crimping a network cable by yourself' below.

Cable (patch cord) for connection of home devices

To connect home network devices to the router, we recommend using factory-made patch cables. These cables are now available almost everywhere in almost any length - UTP/FTP, RJ-45, Cat. 5e (8-core), standard lengths of 3, 5, 7.5, 10, 15, 20, 30, 50, 100 m.


For high quality, reliable connection of devices at 1 Gbit/s, use 8-core factory-manufactured category 5 or higher cables.

If you have a network cable crimping tool, you can make your own patch cable at home, but be very careful to crimp the connectors correctly and properly. For more information on this, see 'Crimping a network cable by yourself' below.

The router must be positioned so that there is no possibility of intermittent physical impact on the cable. If the cable can be pinched, bumped, stepped on or dislodged, it can cause loss of link and data transmission errors.

Sometimes a poor quality RJ45-RJ45 / 8P8C straight-through connector adapter (also called a 'barrel') can be the cause of poor network infrastructure performance. It is usually used to extend the length of a line and allows two shorter patch cords to be used when cable lengths are insufficient.


If your network uses such a connector adapter and you are experiencing problems with the network link, try connecting the cable directly (without an intermediate adapter) to the router or replace the connector adapter.

We recommend replacing the cables that will be used in the flat to connect network devices with factory-made patch cords of the correct length.

Crimping a network cable by yourself

In some cases, if you have minimal knowledge and a network cable crimping tool, you can make a patch cable yourself or re-crimp and replace the 8P8C connector of an Internet cable that is already wired into your flat by your ISP.


If you crimp the network cable yourself, you should follow the existing standard. If you are not skilled and knowledgeable in this matter, please contact your Internet Service Provider with a request.

There are two variants of twisted pair cable crimping: EIA/TIA-568A (T568A) and EIA/TIA-568B (T568B). The T568B direct crimp option is normally used:


No. of cores on one side of the cable core colour No. of the core on the other side of the cable
1 white/orange stripe 1
2 orange solid 2
3  white/green stripe 3
4  blue solid 4
5 white/blue stripe 5
6 green solid 6
7 white/brown stripe 7
8  brown solid 8

NOTE: Important! When crimping the ISP Internet cable yourself, first carefully study the core arrangement in the connector. When replacing the connector, you will need to use the same core layout.

When crimping the cable yourself, all the cores must be inserted all the way into the 8P8C connector, otherwise, it may result in poor or missing contact. The outer sheath of the cable must also fit into the connector and be crimped by it, to ensure that the cores fit securely in the connector. All 8 cores in the cable must be in good condition.

TIP: Note: If you have an unstable link or inadequate connection speed on the router's WAN port, we recommend the following steps:

1. Connect the Internet cable directly to the network adapter on the computer. Check the connection speed. If it also does not match your PC's claimed speed (e.g. the connection speed of an 8-wire ISP cable should be 1 Gbit/s, but you see 100 Mbit/s), you should contact your ISP for a check and diagnosis of your leased line. If you see the correct connection speed when you connect the Internet cable directly to your PC, but when you connect via a router, it is not always possible to determine the cause, either. If the cable is not up to standard, it is possible that one device or device port may still connect and another may not, it is a matter of chance. Cable quality can only be checked with a specialised device, a cable tester, which is usually available to the ISP.

2. Move the ISP cable connection from the router's blue WAN port to any available grey LAN port, such as port 4, as described in step 2 of Changing the operating mode and role of network ports.
Important! Before configuring port mapping, be sure to disconnect the ISP's Internet cable from the router when changing a port role.

3. Disable periodic ISP gateway availability check, as in very rare cases, ISPs will block the connection when such check is detected.
To do this, in the command-line interface (CLI) of the router, sequentially execute the commands:

easyconfig check exclude-gateway
system configuration save

4. Switch on Green Ethernet mode* on the blue WAN port of the router to which the ISP's Internet cable is connected. This will help solve a situation that occurs very rarely when on a cable that is too short; the ISP switch cannot correctly negotiate the link speed at elevated signal levels. In the command-line interface (CLI) of the router, run the following commands in sequence:

interface GigabitEthernet1/0
system configuration save

* Green Ethernet or Energy-Efficient Ethernet mode is a set of enhancements to twisted-pair and backplane Ethernet computer networking standards that reduce power consumption during periods of low data activity. The goal is to reduce power consumption by 50% or more while maintaining full compatibility with existing equipment.

5. On the WAN port, manually set the port mode to '1000Mbps Full Duplex Auto-negotiation' instead of the default Auto-negotiation mode. Go to the 'System settings' page in the 'Management' menu, under 'Network ports', select the mode for the desired port and apply the setting.



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