How to Improve Network performance of websites (Networking point of view)

May 20, 2024 / Balaji Bandi / 0 Comments

To improve the network performance of websites using your Cisco-based environment, you should focus on distinguishing between bandwidth saturation, routing inefficiencies, and hardware-level mismatches.

1. Standard Diagnostic Approach: Network vs. Server

To validate if the bottleneck is network-related rather than server-side, follow these isolation steps:

  • Establish a Performance Baseline: Compare latency and response times during off-peak hours versus peak hours.
  • End-to-End Latency Tests: Use ICMP (Ping) and Traceroute with varying packet sizes from external and internal sources to identify specific hops where delays occur.
  • Simultaneous Resource Checking: If user response times are slow while server CPU and RAM usage are low (check via top or Cisco SWA’s System Status), the bottleneck is likely the network.
  • Check for Interface Errors: On your Cisco routers and switches, use show interfaces to look for CRC errors, input errors, or collisions. These often indicate faulty cables, bad GBICs, or duplex mismatches (e.g., one side is full-duplex while the other is half-duplex). 

2. Cisco-Specific Monitoring Tools

Cisco hardware offers advanced built-in features to pinpoint congestion: 

  • Cisco IP SLA: Configure synthetic transactions to measure jitter and response times for critical services like DNS or web traffic. This provides an independent data source unaffected by user browser behavior.
  • NetFlow: Implement NetFlow to gain granular visibility into who the “top talkers” are, which applications are consuming bandwidth, and if non-essential traffic is crowding out your website’s traffic.
  • SNMP & Syslog: Centralize logs to track interface utilization spikes and hardware-related error logs (e.g., buffer overflows or CPU spikes at 99%). 

3. Networking Best Practices for Content-Heavy Sites

  • Content Delivery Network (CDN): For a content-heavy site, a CDN is essential. It caches static content at edge servers closer to users, significantly reducing the load on your origin server and bypassing internal network congestion.
  • Quality of Service (QoS): Apply QoS policies on your Cisco routers to prioritize web traffic (HTTP/HTTPS) and critical catering application data over background tasks like backups or internal file transfers.
  • Load Balancing: Distribute incoming traffic across multiple servers or paths to prevent any single device from becoming a bottleneck during peak hours.
  • Optimize MTU and Protocols: Ensure that the Maximum Transmission Unit (MTU) sizes match across the network path to avoid packet fragmentation, which significantly slows down data transmission.
  • Network Segmentation: Use VLANs to isolate web server traffic from other corporate traffic, reducing “broadcast storms” and improving overall throughput. 

4. Common Misconfigurations to Verify

  • Mismatched Duplex/Speed: Ensure switch and firewall interfaces are set to auto-negotiate or are manually matched to avoid high error rates.
  • DNS Resolution Delays: Check if your DNS records are outdated or if your DNS server is struggling during peak times, as slow name resolution is a common cause of perceived website slowness.
  • Oversubscribed WAN Links: Verify if your internet circuit bandwidth (WAN) is significantly lower than your internal LAN speed, which creates an unavoidable funnel during high traffic. 

This is not limited; you can create a customised set of KPIs and metrics to perform better.

Happy Labbing !!!!!