Sheet 07
Hop-by-Hop Network Latency Budget
End-to-end request latency decomposition, tail latency amplification (P95/P99), and SLA validation.
SLA CompliancePASS (92.2ms / 150ms)
Uncached P50
85.5 ms
Origin miss + DBCached P50
50.5 ms
Fast path (CDN + Redis)Blended P50
51.2 ms
98% cached / 2% missP95 Tail Latency
92.2 ms
1.8x amplificationP99 Worst 1%
153.6 ms
3.0x amplificationCumulative Hop Latency Waterfall (ms)
Hop-by-Hop Breakdown Matrix
| Network Hop | Hop Latency (ms) | Cumulative (ms) | % of Total | Architectural Context |
|---|---|---|---|---|
| Client -> DNS | 5 ms | 5 ms | 5.8% | Cached in browser/OS after 1st hit |
| DNS -> CDN Edge | 10 ms | 15 ms | 11.7% | Anycast routing to nearest PoP |
| CDN -> Origin (Miss) | 30 ms | 45 ms | 35.1% | Only 2% of traffic on cache miss |
| Origin -> LB | 2 ms | 47 ms | 2.3% | NLB TCP handoff |
| LB -> Gateway | 2 ms | 49 ms | 2.3% | mTLS proxying in private VPC |
| API Gateway | 3.5 ms | 52.5 ms | 4.1% | JWT verify + token bucket + route |
| Gateway -> Service | 1 ms | 53.5 ms | 1.2% | Service mesh sidecar hop (Envoy) |
| Service Processing | 20 ms | 73.5 ms | 23.4% | Core business logic execution |
| Service -> Redis | 1 ms | 74.5 ms | 1.2% | In-memory cache read |
| Service -> Postgres | 5 ms | 79.5 ms | 5.8% | Indexed primary key / foreign key lookup |
| JSON Serialization | 1 ms | 80.5 ms | 1.2% | DTO serialization |
| Reverse Egress Path | 5 ms | 85.5 ms | 5.8% | TLS encapsulation back to client |