What does a red LOS light mean on my Byfly modem?

The blinking red 'LOS' (Loss of Signal) light on your Huawei or ZTE modem means the fiber optic cable is damaged or receiving no signal. Check if the yellow optical cable is firmly plugged in. If it persists, call 123.

How do I fix Error 691 when connecting to Byfly?

Error 691 indicates 'Access Denied' due to an incorrect username/password or unpaid bill. Verify your login credentials in the modem settings (192.168.1.1) and check your balance in the My Beltelecom app.

How do I log into my Byfly modem?

Open a browser and type http://192.168.1.1. Common logins are Username: 'admin', Password: 'admin' (or field left blank). For some Huawei models, the superuser login is 'telecomadmin' / 'admintelecom'.

Why is my Yasna internet slow?

If your speed is well below your plan (e.g., getting 30 Mbps on a 100 Mbps 'Yasna 100' plan), you may be on the 2.4 GHz WiFi band. Switch to the 5 GHz band or use an Ethernet cable for full speed.

Byfly Speed Test

This tool validates Internet speeds for Byfly (Beltelecom) subscribers. Whether you are on a high-speed Fiber Optic Yasna plan or a legacy Domosed (DSL) connection, testing helps confirm you are getting the bandwidth you pay for.

Byfly is the largest state-owned ISP in Belarus. While fiber coverage is extensive, common issues like "Error 691" or slow WiFi on older ZTE/Huawei modems can impact performance.

Interpreting Yasna & Record Results

Download Speed:
- Yasna 100: Should reach ~90-95 Mbps wired.
- Yasna 200/500: Requires a Gigabit router and 5 GHz WiFi to reach full speeds.
- Record Plans: Speeds vary from 10 Mbps to 100 Mbps.
If your result is capped at 95 Mbps, you may be using an old Cat5 cable or a 100M-only router port.

Upload Speed: Typically 50% of your download speed on new Yasna plans (e.g., 50 Mbps upload on a 100 Mbps plan).

Ping (Latency): <5ms to Beltelecom servers (Minsk). 30-50ms to Europe.

Byfly Modem Login (192.168.1.1)

To change your WiFi password or troubleshoot connection errors, access your modem's web interface. Most Byfly modems are ZTE or Huawei.

Modem Brand	Default Login Details
Common (ZTE/Huawei)	http://192.168.1.1 User: admin / Pass: admin
Advanced (Huawei)	User: telecomadmin / Pass: admintelecom (Use only if you know what you are doing)

Troubleshooting Common Errors

Red "LOS" Light: This means Loss of Signal. First, check if the yellow fiber cable is plugged in tightly. If the light stays red or blinks, the fiber line is likely broken. Call 123.

Error 691: "Access Denied". This happens if your username/password is wrong in the PPPoE settings, or if your account has a negative balance. Check "My Beltelecom".

Error 678/651: "Remote Computer Not Responding". Usually a line fault or ISP-side issue. Restart modem; if it fails, call support.

When to Contact Support (123)

Contact Beltelecom support if:

The LOS light is blinking red.

You have verified your balance is positive but still get Error 691.

Your speed is consistently below 50% of your plan rate on a wired connection.

Byfly Speed Test FAQs

Why is my internet slow in the evening? During peak hours (19:00 - 23:00), residential networks can get congested. However, on fiber (GPON), this should be minimal. If significant, check your own WiFi interference.

Can I replace the Byfly modem with my own? You cannot easily replace the optical (ONT) modem because it must authenticate with Beltelecom. However, you can buy a powerful router, connect it to the Byfly modem, and ask support to switch your modem to "Bridge Mode".

How do I check my balance? Use the "My Beltelecom" app or visit the user cabinet (issa.beltelecom.by) to see your balance and payment history.