Traceroute: Diagnosing Your Internet Path

Direct Answer

Traceroute is a diagnostic tool that shows the path a packet takes from your device to a destination server, listing every router (hop) along the way.

Overview

When you experience lag or slow speeds, traceroute helps you identify if the problem is inside your home, at your ISP, or in the international undersea cables.

Technical Deep-Dive

Traceroute works by sending packets with increasing Time-to-Live (TTL) values.

1. The first packet has a TTL of 1, so it “dies” at the first router.
2. The router sends back an ICMP “Time Exceeded” message.
3. Traceroute records the router’s IP and the time taken.
4. This repeats until the destination is reached.

Bangladesh Context

In Bangladesh, analyzing a traceroute requires understanding the local hierarchy:

• Hops 1-2: Usually your home router and the ISP’s local gateway. High latency here means a local issue.
• Hops 3-5: Typically the NTTN or IIG (International Internet Gateway) like Fiber@Home or Summit.
• The Jump to Singapore: For most Bangladeshi users, the path goes through the SMW-4 or SMW-5 submarine cables to Singapore (SGX). You will typically see a sudden jump in latency from ~5ms to ~40-60ms here.
• BDIX Hops: If you are tracerouting a local service (like a BDIX FTP or TV server), the hops should stay within Bangladesh, and latency should remain under 10ms.

Troubleshooting

• Asterisks ()*: This doesn’t always mean a failure; many routers (especially in Bangladesh) are configured to ignore ICMP requests for security.
• High Latency at the First Hop: This indicates an issue with your Wi-Fi or router, not the ISP.

FAQ

What is a good traceroute time?

To a local BDIX server: <10ms. To Singapore: 35-60ms. To Europe/USA: 140-250ms.

References

• RFC 1393: Traceroute using an IP Option
• Bangladesh Submarine Cable Company Limited (BSCCL) Path Maps