Severe Network Degradation and Local Issues | Generated by AI

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Question: Explain this MTR result to 185.199.108.153 and compare it with the previous trace to 104.21.78.239.

Answer:

This trace is worse than your previous one and shows two real problems:

Severe local network instability
Heavy packet loss on international route (China → Japan → GitHub CDN)

Let’s analyze carefully.

1. Final destination (this determines real quality)

13. cdn-185-199-108-153.github.com
Loss 52.3%
Avg 148.9 ms

This is very bad:

❌ 52% packet loss
⚠️ unstable latency
❌ half of packets dropped

This will cause:

git clone hanging
npm/pip slow
GitHub downloads fail
API timeout
CI/CD failures

So this route is severely degraded.

2. The biggest red flag — your local network

1. 192.168.1.1
Loss 27.1%
Avg 28.8 ms
Worst 245 ms

This is extremely abnormal.

Local router should be:

0% loss
< 3 ms latency

Your result:

❌ 27% packet loss
❌ huge jitter
❌ 245 ms spikes

This means your WiFi / LAN is already broken before reaching ISP.

So everything after this is affected.

3. Route path

Your route:

home router
  ↓
China Telecom (Guangdong)
  ↓
China Telecom backbone
  ↓
203.86.97.18  ← leaving China
  ↓
NTT Japan backbone
tokyjp05
tokyjp10
  ↓
Fastly CDN
  ↓
GitHub CDN

So this path is:

China Telecom → NTT Japan → Fastly → GitHub

This is normal GitHub route from China.

4. Where loss becomes real

Loss persists all the way to destination:

hop 1  27%
hop 2  17%
...
hop 9  54%
hop 12 51%
hop 13 52%

Because final hop still has 52%, this is real packet loss.

5. Compare with your previous test (Cloudflare)

Previous (Cloudflare):

loss: 6%
latency: 270 ms

This one (GitHub CDN):

loss: 52%
latency: 148 ms

Comparison:

Test	Destination	Loss	Latency	Quality
first	Cloudflare	0%	260ms	good
second	Cloudflare	6%	270ms	medium
third	GitHub CDN	52%	148ms	terrible

So:

Cloudflare route = mostly OK
GitHub route = very unstable

This is very common in China.

6. Why GitHub worse than Cloudflare

Because:

Cloudflare:

China Telecom → Cloudflare direct peering

GitHub CDN:

China Telecom → NTT → Fastly → GitHub

More hops + congested transit.

GitHub CDN often unstable in China.

7. But the real root cause

Your local network already broken:

hop 1 loss 27%

Even if upstream perfect, you’d still have issues.

So you must fix:

WiFi interference
router CPU overload
bufferbloat
2.4GHz congestion
bad cable
QoS misconfig

8. What this means practically

You currently have:

❌ unstable WiFi
❌ ISP congestion
❌ GitHub route congestion

Triple problem.

That’s why GitHub feels very slow.

9. Quick tests

Run this:

ping 192.168.1.1

If loss > 0% → WiFi problem.

Then try:

wired ethernet

You will likely see:

loss drop to 0%
latency stable

Final conclusion

This trace shows:

❌ 52% real packet loss to GitHub CDN
❌ local router already unstable (27% loss)
⚠️ China Telecom → Japan congestion
⚠️ GitHub CDN route worse than Cloudflare

Main problem order:

your WiFi / LAN (biggest)
ISP international congestion
GitHub route weaker than Cloudflare

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