How To Use Korean Native IP With CDN And Load Balancing In Enterprise-level Solutions To Improve Experience

1.

Overall architecture overview and design goals

• Goal: Reduce page time to first byte (TTFB) to ≤120ms for Korean users, and page load 95th percentile to ≤300ms.
• Architecture points: Korean native IP serves as edge outbound, combined with load balancing of multi-point CDN nodes and active health detection.
• Involved components: domain name resolution (GSLB/GeoDNS), CDN (PUSH/POP cache), local Edge VPS (native IP), central origin site and DDoS cleaning.
• Network strategy: Use Korean ISP native IP segments (such as /29 or /28 small network segments) to directly connect to local operators to avoid increased packet loss and delay caused by international export NAT.
• Operation and maintenance goal: SLA 99.95%, rapid switching to backup origin sites and cleaning nodes, ensuring smooth rollback of peak concurrency.

2.

Server/VPS and network configuration recommendations

• Origin site configuration example: SG origin VPS: 8 vCPU / 16GB RAM / 1Gbps bandwidth, SSD NVMe 200GB, Linux + Nginx 1.22.
• Korean edge configuration: 4 nodes, each node 4 vCPU / 8GB / 500Mbps, allocated Korean native IPv4 /29 (or allocated by ISP on demand), BGP direct connection.
• Load balancing: HAProxy or LVS + Keepalived, health check 5s/3 failed switchovers, session stickiness enabled on demand.
• CDN strategy: TTL 3600s for static resources, dynamic interfaces through edge acceleration and cache sharding (Cache-Control + Edge-Side Includes).
• Domain name and DNS: Use GeoDNS for preliminary traffic distribution, and combine it with GSLB to distribute traffic to the nearest Edge based on region + health.

3.

Details of collaboration between CDN and load balancing

• Edge preferentially uses Korean native IP for outbound traffic, reducing the number of ISP NAT hops and improving connectivity rate and delay stability.
• CDN serves as the first layer cache, with a cache hit rate target of ≥85%. Cache misses are returned to the origin from the nearest Edge, and then to the central origin site.
• Load balancing strategy: Weighted-round-robin based on response delay and number of connections, automatic expansion and contraction in case of burst traffic.
• Health check content: TCP/HTTP detection + custom business detection (interface return code and response time).
• Logging and monitoring: Collect real-time RTT, packet loss and QPS of Edge and LB, and use Prometheus+Grafana to set alarm thresholds.

4.

DDoS defense and fault drill

• Protection link: Connect to the local scrubbing center or cloud vendor's DDoS protection. Capacity example: scrubbing capacity ≥100Gbps, 10Mpps.
• Edge current limiting: Configure rate limits and connection thresholds on Edge and LB (for example, concurrent connections per source IP ≤ 200, requests per second ≤ 50).
• Switching strategy: After automatically detecting attacks (sudden increase in traffic, abnormal connections), GSLB delivers black holes or diverts traffic to cleaning nodes.
• Regular drills: Conduct traffic switching and DDoS drills every quarter to verify RTO ≤ 5 minutes.
• Compliance and filing: Complete IP/domain name filing and compliance testing in accordance with local Korean regulations and ISP requirements.

5.

Real cases and performance data examples

• Case introduction: Before a multinational e-commerce company used Korean native IP, Korean users accessed the Singapore origin site through international NAT. After the transformation, 4 native IP Edges were deployed in Korea and connected to CDN and HAProxy load balancing.
• Optimization results (observation period 30 days): The local RTT median dropped from 170ms to 28ms, and the page 95th percentile dropped from 1.2s to 260ms.
• DDoS incident: It was attacked by 42Gbps/4.2Mpps, and the traffic was diverted to the local cleaning center. The service degradation time was <6 minutes, and the traffic was restored to normal.
• Operation and maintenance costs: Additional edge VPS and native IP fees account for about 18% of the total cost, but the increase in conversion rate and user retention bring significantly better ROI.
• Recommendation: 2-4 nodes can be used as a pilot in the initial stage, and the capacity can be expanded according to QPS and geographical distribution after monitoring.

6.

Configuration and performance data table (example)

7.

Implementation points and implementation suggestions

• First conduct a small-scale A/B test to verify the performance difference of native IP on major ISPs (KT, SK Broadband, LG U+).
• Communicate with CDN and local ISP to confirm BGP, routing and reverse DNS settings to avoid blacklist misjudgment.
• Monitor the delay and packet loss of each hop of the link from the Edge to the source site, and set automated alarms and rollbacks.
• Cost evaluation: Evaluate ROI based on peak bandwidth and IP segment rental cost, with priority given to ensuring peak bandwidth in Korea.
• Long-term optimization: Adjust caching strategies and load scheduling based on user behavior analysis to continuously reduce costs and improve experience.