How to Fix Slow Internet in Your Dubai Office: ISP Problem or Internal Network?

The Most Common Mistake: Blaming the ISP First

In our experience supporting Dubai offices, roughly 60% of slow internet complaints are caused by internal network issues — not the ISP. Testing correctly before calling saves hours.

15-Minute Diagnosis Protocol

Test 1: Direct ISP Connection

Connect a laptop directly to the ISP modem or ONT with an Ethernet cable. Bypass your router completely.

Run a speed test on speedtest.net. If speed matches your contracted plan, the ISP is fine — your internal network is the problem.

Test 2: Isolate to One Device

Is only one user affected, or is it office-wide?

• One user: Check their machine — DNS, browser, proxy, or antivirus scanning downloads
• Multiple users on same VLAN: Check uplink, switch port, or VLAN firewall policy
• All users: Check firewall WAN interface, then ISP line

Test 3: Check Firewall WAN Utilisation

On FortiGate, check WAN interface traffic graph. If bandwidth is saturated, run top-traffic report to find the source.

Common culprits in Dubai offices:

Test 4: DNS Performance

Slow DNS adds latency to every web request even when bandwidth is fine.

Compare DNS resolution time from your firewall versus a public resolver like 8.8.8.8. If your firewall DNS is significantly slower, switch to a faster upstream resolver or enable DNS over HTTPS.

ISP Escalation Checklist

Before calling:

• Screenshot speed test results (3 runs, different times of day)
• Note if problem is time-specific (only during business hours suggests contention)
• Confirm link light status on modem or ONT
• Check ISP status page for outages in your building or zone

*Related: Networking and Security Dubai | IT AMC Dubai*