Cisco AIM-VPN/SSL-2
DES/3DES/AES/SSL VPN Encryption/Compression
Product Highlights
What's Included
As VPN traffic grows across branch offices and remote workforces, software-based encryption can quickly become a bottleneck on your router's CPU. The Cisco AIM-VPN/SSL-2 solves this by offloading DES, 3DES, AES, and SSL VPN encryption — plus Layer 3 IPPCP compression — into dedicated hardware on your Cisco 2800 Series Integrated Services Router.
This Advanced Integration Module (AIM) is a cryptographic accelerator that installs into any open AIM slot on the Cisco 2801, 2811, 2821, or 2851. It delivers up to 40 percent better IPsec VPN performance and up to twice the SSL Web VPN throughput compared to the router's built-in software encryption. With support for up to 1,500 simultaneous VPN tunnels on the Cisco 2800 Series, the AIM-VPN/SSL-2 is built for demanding multi-site and remote-access deployments.
By consolidating IPsec and SSL VPN acceleration into a single plug-in module, the AIM-VPN/SSL-2 reduces the need for standalone encryption appliances — lowering total cost of ownership while simplifying network management. It is ideal for SMBs, enterprise branch offices, and service providers seeking scalable, hardware-accelerated VPN services on the Cisco ISR platform.
Features & Benefits
Hardware Cryptographic Acceleration
The AIM-VPN/SSL-2 offloads computationally intensive encryption and decryption tasks from the router's main CPU to a dedicated hardware engine. This frees up processor resources for routing, firewall, and other services — ensuring consistent performance even under heavy VPN workloads.
Multi-Algorithm Encryption
Supports DES, 3DES, and AES (128-bit, 192-bit, and 256-bit key lengths) for IPsec VPN, plus SSL encryption for Web VPN sessions. This breadth of algorithm support ensures compliance with a wide range of security policies and regulatory requirements.
SSL VPN Acceleration
Provides hardware-based SSL VPN encryption, delivering up to twice the performance of software-only SSL processing. SSL VPN throughput scales with the host platform — from 5 Mbps on the Cisco 2801 up to 14 Mbps on the Cisco 2851 — supporting between 50 and 150 concurrent SSL VPN users depending on the router model.
Layer 3 IPPCP Compression
Hardware-accelerated IP Payload Compression Protocol (IPPCP) reduces the size of encrypted payloads before transmission. This conserves WAN bandwidth and improves effective throughput, particularly valuable for bandwidth-constrained branch office links.
Scalable Tunnel Support
The module supports up to 1,500 VPN tunnels on the Cisco 2800 Series, enabling large-scale site-to-site DMVPN deployments and extensive remote-access VPN environments. This scalability makes it suitable for growing enterprise networks and managed service provider offerings.
Simple AIM Slot Installation
The plug-in module form factor fits into any open AIM slot on compatible Cisco ISRs. Installation requires no additional rack space or external cabling — simply insert the module and configure via Cisco IOS CLI to begin accelerating VPN traffic.
Deployment Scenarios
Enterprise Branch Office VPN
Deploy the AIM-VPN/SSL-2 in Cisco 2800 Series routers at branch offices to accelerate site-to-site IPsec VPN tunnels back to headquarters. Hardware encryption offload ensures that routing and security services continue to perform well even as VPN traffic scales.
Remote Access SSL VPN
Enable hardware-accelerated SSL VPN for remote and mobile workers connecting to the corporate network through a Cisco 2800 Series router. The module supports up to 150 concurrent SSL VPN users (on the Cisco 2851), providing secure clientless browser-based access without degrading router performance.
Managed Security Service Provider (MSSP)
Service providers can leverage the AIM-VPN/SSL-2 to deliver scalable, hardware-accelerated managed VPN services to multiple customers from Cisco 2800 Series CPE routers. Zero-touch deployment capabilities and support for up to 1,500 tunnels simplify large-scale service delivery.
Dynamic Multipoint VPN (DMVPN)
Accelerate DMVPN hub or spoke deployments on Cisco 2800 Series routers. The hardware encryption engine handles the high volume of dynamic tunnel establishment and teardown inherent in DMVPN topologies, maintaining low latency and high throughput.
General
Performance
Security & Encryption
Physical
Environmental
Software Requirements
Compatibility Notes
Compatible Platforms
- Cisco 2801 — SSL VPN: 5 Mbps, max 50 users
- Cisco 2811 — SSL VPN: 5 Mbps, max 75 users
- Cisco 2821 — SSL VPN: 10 Mbps, max 100 users
- Cisco 2851 — SSL VPN: 14 Mbps, max 150 users
Requirements
- One available AIM slot in a compatible Cisco Integrated Services Router
- Cisco IOS Software Version 12.4(9)T or higher with an Advanced Security, Advanced IP, or equivalent feature set
- One encryption module per router (only one AIM-VPN/SSL module supported per chassis)
Notes
- The AIM-VPN/SSL-2 is specifically designed for the Cisco 2800 Series. For the Cisco 1841, use the AIM-VPN/SSL-1. For the Cisco 3800 Series, use the AIM-VPN/SSL-3.
- This product has been retired by Cisco. It remains fully functional in supported platforms but is no longer available for new purchase from Cisco.
Downloads & Resources
Frequently Asked Questions
| Part Number | Product | Key Difference |
|---|---|---|
| AIM-VPN/SSL-1 | Cisco AIM-VPN/SSL-1 VPN Encryption Module | Designed for the Cisco 1841 router; same encryption capabilities but optimized for the 1800 Series platform. |
| AIM-VPN/SSL-3 | Cisco AIM-VPN/SSL-3 VPN Encryption Module | Designed for the Cisco 3800 Series; higher SSL VPN throughput (up to 26 Mbps) and support for up to 2,000 tunnels. |
| AIM-VPN/EPII-PLUS | Cisco AIM-VPN/EPII-PLUS Encryption Module | Earlier-generation AIM VPN module for Cisco 2600XM/2691 routers; supports DES/3DES/AES but lacks SSL VPN acceleration. |
