F5 BIG-IP LTM 3400 vs i4600: Entry-Level vs Mid-Range ADC Performance Analysis

When evaluating F5 Networks' application delivery controllers, the BIG-IP LTM 3400 (entry-level model) and BIG-IP i4600 (mid-range solution) cater to different segments of the market. This detailed comparison examines their technical specifications, operational capabilities, and ideal deployment scenarios to help network administrators select the right solution for their infrastructure needs.

Technical Specifications Comparison

The i4600 delivers 2-2.5x greater performance across all key metrics compared to the entry-level LTM 3400.

Functional Capabilities Analysis

1. Core ADC Features

Both models provide:

• Layer 4-7 load balancing

• SSL/TLS offloading

• Application health monitoring

• Basic web application firewall

• DNS load balancing

i4600 Advantages:

• 2x greater connection capacity

• Better SSL inspection throughput

• More advanced traffic shaping

• Enhanced DDoS protection

LTM 3400 Strengths:

• More power-efficient

• Lower acquisition cost

• Suitable for small deployments

2. Security & Traffic Management

• i4600 excels in:

• Higher volume traffic inspection

• Advanced rate shaping

• Detailed performance analytics

• LTM 3400 optimized for:

• Basic security policies

• Light to moderate traffic

• Simple WAF configurations

Physical Design Comparison

Chassis Architecture:

• LTM 3400:

• 1RU compact form factor

• Single power supply

• Front-accessible ports

• Office-friendly design

• i4600:

• 1RU enterprise design

• More robust cooling

• Higher port density

• Data center optimized

Environmental Specifications:

• Operating temperature:

• Both: 0°C to 40°C

• Physical dimensions:

• Both: 1RU, 17.5" deep

• Weight:

• LTM 3400: 16 lbs

• i4600: 20 lbs

User Experience Evaluation

Administration & Management:
Both utilize:

• F5 TMOS operating system

• Web-based GUI

• tmsh CLI

• Basic REST API support

Operational Differences:

• i4600 better for:

• More complex configurations

• Higher availability requirements

• Multi-site deployments

• LTM 3400 ideal for:

• Simple administration

• Small office deployments

• Minimal operational overhead

Pricing & Cost Analysis

Acquisition Costs:

• LTM 3400: 18,000−25,000

• i4600: 35,000−45,000

Operational Expenditures:

• Power consumption difference: ~$100/year

• Support contracts:

• Similar licensing models

Five-Year TCO Considerations:

• i4600 justified for:

• Growing businesses

• Performance-sensitive apps

• Future expansion

• LTM 3400 economical for:

• Small business needs

• Light workloads

• Tight budgets

Power Efficiency Metrics

Energy Usage:

• LTM 3400: 120W (peak)

• i4600: 220W (peak)

Efficiency Comparison:

• Performance per watt:

• LTM 3400: 66 Mbps/W

• i4600: 90 Mbps/W

• Idle power draw:

• LTM 3400: 80W

• i4600: 120W

Compatibility & Expansion

Third-Party Integration:
Both support:

• Basic virtualization platforms

• Cloud connectivity

• Limited API automation

i4600 Advantages:

• More interface options

• Better scalability

• Advanced SDN support

Software Support & Roadmap

Current Software Features:

• Both run TMOS 16.x+

• Support basic iRules

Future Development:

• i4600 prioritized for:

• Core feature updates

• Security enhancements

• LTM 3400 receives:

• Maintenance updates

• Basic security patches

Final Recommendation

Choose LTM 3400 When:
✔ Small business needs
✔ Budget under $25,000
✔ Light application traffic
✔ Simple deployments

Select i4600 When:
✔ Medium business requirements
✔ Need 20G throughput
✔ Planning growth
✔ Require better performance

Implementation Strategy:
For organizations anticipating growth, the i4600 provides better long-term value, while the LTM 3400 serves well for fixed, small-scale deployments. Consider future needs when selecting between these models.

Key Differentiators:

1. Performance: i4600 handles 2x more traffic

2. Scalability: Better growth potential

3. Features: More advanced capabilities

4. Cost: LTM 3400 more affordable upfront

Both deliver F5's reliable ADC technology at different performance and price points, with the i4600 offering better value for growing organizations and the LTM 3400 serving basic needs at a lower cost.