Cisco WS-X6624-FXS
Catalyst 6000 24 port FXS Analog Station Interface Module
Product Highlights
Organizations with legacy analog telephony equipment face a critical challenge: how to integrate existing analog phones, fax machines, and conference room speakerphones into a modern IP-based network without costly forklift upgrades. The Cisco WS-X6624-FXS Catalyst 6000 24-Port FXS Analog Station Interface Module solves this problem by providing a seamless bridge between traditional analog endpoints and your VoIP infrastructure.
Designed as a hot-swappable line card for the Cisco Catalyst 6000 and 6500 Series chassis, the WS-X6624-FXS delivers 24 Foreign Exchange Station (FXS) ports through a single RJ-21 connector. Each FXS interface emulates a central office (CO) or private branch exchange (PBX), supplying ring voltage, dial tone, and standard loop-start signaling — so connected analog devices operate exactly as if they were attached to a traditional telephone line. The module supports G.711, G.729, and G.729A voice codecs along with silence suppression, voice activity detection, and comfort noise generation for efficient bandwidth utilization.
By enabling legacy analog devices to communicate over your IP network, the WS-X6624-FXS unlocks toll-bypass capabilities and allows analog endpoints to interact with IP phones, H.323 terminals, and other VoIP devices. This makes it an ideal solution for enterprises transitioning to unified communications while preserving their investment in existing analog equipment. Note: This product has reached End-of-Life status; Cisco recommended the Communication Media Module (CMM) as the migration path.
Features & Benefits
24-Port FXS Analog Connectivity
The WS-X6624-FXS provides 24 FXS ports that connect directly to standard analog telephones, fax machines, and conference room speakerphones. Each port emulates a CO or PBX line, supplying ring voltage and dial tone so that connected devices operate transparently — no end-user retraining or device replacement required.
Advanced Voice Encoding & Bandwidth Optimization
Supporting G.711, G.729, and G.729A codecs, the module lets administrators balance voice quality against available bandwidth. Silence suppression, voice activity detection (VAD), and comfort noise generation further optimize WAN utilization by transmitting data only when speech is detected, reducing unnecessary traffic during call idle periods.
Toll-Bypass & IP Integration
By routing analog voice traffic over your existing IP network infrastructure, the WS-X6624-FXS enables toll-bypass applications that can significantly reduce long-distance telephony costs. Connected analog devices can communicate with IP phones, H.323 endpoints, and other VoIP-enabled devices across the enterprise.
Hot-Swappable Design
The module's hot-swappable form factor allows installation and replacement in any available slot of a Catalyst 6000/6500 chassis without powering down the switch. This minimizes downtime during deployment, upgrades, or maintenance windows — critical for production voice environments.
High-Density RJ-21 Cabling
All 24 FXS ports are accessed through a single RJ-21 connector on the module's front panel, consolidating cabling into one high-density interface. This simplifies cable management in dense wiring closets and reduces the physical footprint compared to individual per-port connectors.
Deployment Scenarios
Legacy Analog Phone Integration
Enterprises migrating to VoIP can use the WS-X6624-FXS to connect existing analog desk phones and lobby phones to the IP network without replacing handsets. This preserves the investment in analog equipment while enabling unified communications features across the organization.
Fax Machine & Modem Connectivity
Many organizations still rely on analog fax machines for legal, healthcare, or compliance workflows. The WS-X6624-FXS provides dedicated FXS ports for fax machines, ensuring reliable fax transmission over the IP infrastructure with appropriate codec and modem transport support.
Conference Room Speakerphones
Analog conference room speakerphones can be connected through the FXS module, allowing meeting rooms to leverage the IP telephony network for internal and external calls without requiring dedicated analog lines from the PSTN.
Branch Office Toll Bypass
Branch offices equipped with Catalyst 6000/6500 switches can use the WS-X6624-FXS to route inter-office analog voice calls over the WAN, bypassing PSTN toll charges and reducing monthly telecommunications expenses.
General
Interfaces & Ports
Voice & DSP Features
FXS Interface Features
Physical
Power
Compliance
Compatibility Notes
Platform Compatibility
- Chassis: Cisco Catalyst 6000 and Catalyst 6500 Series Switches
- Slot Requirement: Any available module slot (Slot 1 reserved for Supervisor Engine; Slot 2 for redundant Supervisor if applicable)
Software Requirements
- CatOS: Versions 5.5(1), 5.5(3), 6.x, 7.x, 8.x
- Recommended CatOS Version: 6.3(7)
- Supervisor Engine 720: Not supported on CatOS 8.1(x); supported on CatOS 8.2(1) and later
Cabling
- Requires an RJ-21 cable (not included with module) to break out to individual analog device connections
End-of-Life Notice
- Last Order Date: May 15, 2005
- End of TAC Support: May 15, 2010
- Cisco-Recommended Replacement: Cisco Communication Media Module (WS-SVC-CMM)
Downloads & Resources
Frequently Asked Questions
| Part Number | Product | Key Difference |
|---|---|---|
| WS-SVC-CMM | Cisco Communication Media Module | Cisco-recommended replacement for WS-X6624-FXS; supports up to 72 FXS ports per slot with modular port adapters |
| WS-SVC-CMM-24FXS | CMM with 24-Port FXS Port Adapter | Direct functional replacement on the CMM platform; same 24-port FXS density with next-generation architecture |
| WS-X6624-FXS= | WS-X6624-FXS (Spare) | Same module sold as a spare/replacement part (= suffix denotes spare SKU) |