F5 BIG-IP LTM i5800 vs F5 BIG-IP i4600: High-End vs Mid-Range Application Delivery Controllers

When selecting an application delivery controller (ADC), choosing between the F5 BIG-IP LTM i5800 (high-end model) and the F5 BIG-IP i4600 (mid-range model) depends on performance needs, scalability, and budget. This comparison breaks down their technical specifications, functional differences, and ideal use cases to help network administrators make the right decision.

Technical Specifications Comparison

The i5800 offers double the performance in processing power, memory, and throughput, making it ideal for large-scale enterprise deployments, while the i4600 provides a cost-effective solution for medium-sized businesses.

Functional Capabilities Analysis

1. Core ADC Features

Both models support:

• Layer 4-7 load balancing

• SSL/TLS offloading

• Application health monitoring

• Web application firewall (WAF)

• DNS load balancing

i5800 Advantages:

• Higher connection handling (2M vs 1M)

• Better SSL inspection performance

• Advanced traffic shaping for large-scale environments

i4600 Strengths:

• Sufficient for most mid-sized businesses

• Lower power consumption

• More budget-friendly

2. Security & Traffic Management

• i5800 excels in:

• High-volume DDoS protection

• Advanced rate shaping

• Granular traffic analytics

• i4600 is optimized for:

• Standard security policies

• Moderate traffic loads

• Basic WAF configurations

Design & Physical Comparison

Chassis & Build:

• i5800:

• 2RU form factor

• Redundant power supplies (optional)

• High-density port configuration

• i4600:

• 1RU compact design

• Single power supply

• Space-efficient for smaller data centers

Environmental Specs:

• Operating temperature: 0°C to 40°C (both)

• Weight:

• i5800: 30 lbs

• i4600: 20 lbs

• Noise levels:

• i5800: 65 dB (higher due to cooling needs)

• i4600: 55 dB (quieter operation)

User Experience & Management

Administration:

• Both use F5 TMOS (Traffic Management Operating System)

• Web-based GUI (F5 Configuration Utility)

• CLI access via tmsh (TMOS Shell)

• REST API for automation

Operational Differences:

• i5800 is better for:

• Large enterprises with complex policies

• High-availability setups

• Multi-tenant environments

• i4600 is ideal for:

• Simpler deployments

• Single-site load balancing

• Lower administrative overhead

Pricing & Cost Analysis

Initial Purchase Cost:

• i5800: $65,000–$80,000

• i4600: $35,000–$45,000

5-Year TCO Considerations:

• i5800 justified for:

• High-traffic websites

• Financial services with strict compliance

• Cloud-scale ADC needs

• i4600 more economical for:

• Medium business applications

• Branch office deployments

• Cost-sensitive projects

Power Efficiency & Consumption

Energy Usage:

• i5800: 350W (peak)

• i4600: 220W (peak)

Efficiency Metrics:

• Performance per watt:

• i5800: 114 Mbps/W

• i4600: 90 Mbps/W

• Idle power draw:

• i5800: 180W

• i4600: 120W

Compatibility & Expansion Options

Third-Party Integration:

• Both support:

• VMware, KVM, Hyper-V

• AWS, Azure, GCP

• Ansible, Terraform automation

i5800 Advantages:

• More 25G/40G ports for high-speed networks

• Better scalability for future upgrades

• Supports advanced SDN integrations

i4600 Limitations:

• Fewer high-speed ports

• Limited expansion slots

Software Support & Longevity

Current Software Versions:

• Both run TMOS 16.x+

• Support for iRules, iApps, iControl REST API

Maintenance & Updates:

• i5800 receives:

• Priority firmware updates

• Extended security patches

• i4600 has:

• Standard support lifecycle

• Regular vulnerability fixes

Future-Proofing:

• i5800 will likely get:

• AI-driven traffic optimization

• Enhanced cloud ADC features

• i4600 may see:

• Basic feature updates

• Gradual phase-out in 5+ years

Final Recommendation

Choose the F5 BIG-IP LTM i5800 if:
✔ Handling millions of connections
✔ Need 40G+ throughput
✔ Running mission-critical applications
✔ Budget allows for premium performance

Opt for the F5 BIG-IP i4600 if:
✔ Managing moderate traffic (up to 20Gbps)
✔ Require cost-effective ADC
✔ Deploying in smaller data centers
✔ Don’t need ultra-high scalability

Best Deployment Strategy:

• Use i5800 for core data centers

• Deploy i4600 for branch offices or DR sites

Both models deliver F5’s industry-leading ADC capabilities, but the choice depends on scale, performance needs, and budget.