🛡️ Cisco ASA 5506-X vs ASA 5516-X (legacy)
AI-powered analysis across 26 matched specifications


Performance Overview
Scores based on quantifiable specification values (1-10 scale)
Detailed Specifications
| Specification | Cisco ASA 5506-X / 5508-X Cisco | Cisco ASA 5516-X / 5525-X / 5545-X Cisco |
|---|---|---|
| Key Metrics | ||
| Stateful firewall throughput | 750 Mbps (5506-X) / 1 Gbps (5508-X) | 1.8 Gbps (5516-X) / 2 Gbps (5525-X) / 3 Gbps (5545-X) |
| Form factor | Desktop (5506-X) / 1U (5508-X) | 1U rack-mount |
| Built-in interfaces | 8 × GE RJ45 | 8 × GE RJ45 (5516-X); GE + SFP options on 5525-X/5545-X |
| FirePOWER Services | Yes (software module — IPS, AVC) | Yes (NGIPS, AVC, URL filtering) |
| Lifecycle status | End-of-sale / end-of-support — migration required | End-of-sale / end-of-support — migration required |
| Recommended replacement | Firepower 1010 / 1120 | Firepower 1140 / 2110 / 2130 |
| Throughput & Performance | ||
| Stateful inspection (max) | 1 Gbps (5508-X) | 3 Gbps (5545-X) |
| NGFW / FirePOWER throughput (typical) | ~125–175 Mbps with IPS+AVC | ~450–1,000 Mbps with IPS+AVC depending on model |
| IPsec VPN throughput | ~100–175 Mbps | ~250–400 Mbps depending on model |
| Maximum concurrent sessions | 50,000 (5506-X) / 100,000 (5508-X) | 250,000 (5516-X) / 500,000 (5525-X) / 750,000 (5545-X) |
| New connections per second | ~5,000 (5506-X) / ~10,000 (5508-X) | ~20,000–30,000 depending on model |
| Connectivity | ||
| Copper GE ports | 8 × 10/100/1000 RJ45 | 8 × GE RJ45 (5516-X); fewer on 5525/5545 with SFP slots |
| SFP / fibre uplinks | No | Yes on 5525-X (6 × SFP) / 5545-X (6 × GE + SFP) |
| Management port | Dedicated GE management | Dedicated GE management |
| USB / Console | USB + RJ45 console | USB + RJ45 console + mini-USB |
| Security Services & Management | ||
| IPS / NGIPS | FirePOWER Services module (Snort-based) | FirePOWER Services module (Snort-based, NGIPS) |
| Application Visibility & Control | Yes (via FirePOWER) | Yes (via FirePOWER) |
| URL filtering | Yes (subscription) | Yes (subscription) |
| AnyConnect remote-access VPN | Up to 50 users (5506-X) / 100 (5508-X) | Up to 300 (5516-X) / 750 (5525-X) / 2,500 (5545-X) |
| Management options | ASDM, FMC, CLI | ASDM, FMC, CLI |
| High availability | Active/standby (5508-X); 5506-X limited | Active/active and active/standby |
| Lifecycle & UK Support | ||
| End-of-sale date | 31 August 2022 | 31 August 2022 (5516-X); earlier for 5525/5545 |
| End of software maintenance | 31 August 2023 | 31 August 2023 |
| Last day of support | 31 August 2027 | 31 August 2027 (varies by SKU) |
| Smart Net Total Care | Available within EoL window | Available within EoL window |
| Migration path | Firepower 1010 (desktop) / 1120 (1U) | Firepower 1140 / 2110 / 2130 |
Expert Analysis
Both of these platforms are end-of-sale Cisco ASA appliances, so the honest starting point for any UK buyer is that this is a migration conversation, not a purchasing one. Cisco stopped selling the 5506-X, 5508-X, 5516-X, 5525-X and 5545-X in August 2022, software maintenance ended in 2023, and the last day of support falls in 2027 (with some SKUs earlier). Running these as your primary perimeter past 2025 carries real audit and insurance exposure under NCSC guidance, GDPR Article 32 and any FCA or NHS DSPT obligations you sit under.
If you are comparing the two for a like-for-like spares purchase or a short-term refresh, the 5516-X family is the materially stronger platform. The 5516-X delivers 1.8 Gbps stateful throughput against the 5506-X's 750 Mbps, supports SFP uplinks on the 5525-X and 5545-X, scales to 750,000 concurrent sessions on the 5545-X versus 50,000 on the 5506-X, and supports proper active/active HA. The 5506-X and 5508-X were built for small branches and home-office use; their FirePOWER performance with IPS and AVC enabled drops to roughly 125–175 Mbps, which is below what most UK SME broadband circuits now deliver.
Management is essentially identical — ASDM, FMC and CLI across both ranges — and both run the same FirePOWER Services module, so there is no security-feature differentiator beyond raw performance and session scale. Neither receives new threat-defence features; both are frozen on legacy code trains.
Our recommendation framework: if you are a small branch or retail site currently on a 5506-X or 5508-X, plan a direct hop to a Firepower 1010 or 1120 running FTD — do not buy more 5506-X kit. If you run a 5516-X, 5525-X or 5545-X at a head office or data centre, the Firepower 1140, 2110 or 2130 is the appropriate replacement and will give you 3–10× the NGFW throughput along with a supported software roadmap. Use Smart Net renewals on the existing ASAs only to bridge the migration window, not as a long-term strategy.
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