Cisco SPA504G Full English Product Description

Listing Title

Cisco SPA504G Small Business 4-Line PoE IP Desk Phone, Backlit 128×64 Monochrome LCD Graphical Display, Dual 10/100 Fast Ethernet Switched Ports with PC Pass-Through, Full-Duplex HD Wideband Speakerphone, 2.5mm TRS Headset Jack, Dual SIP / SPCP Telephony Protocol Support, SRTP/TLS Encrypted Secure Voice Communications, Automated TFTP/HTTP/HTTPS Remote Provisioning, Compatible with up to Two SPA500S Attendant Expansion Consoles, End-of-Sale Legacy SMB VoIP Endpoint, Ideal for Office Managers, Administrative Staff, Retail Supervisors and Multi-Line Small Business Voice Deployments

Full Commercial Overview

The Cisco SPA504G is a mid-tier four-line LCD VoIP desk phone within Cisco’s Small Business SPA500 Series product lineup, designed for office administrators, managers and retail supervisors who need multiple concurrent call lines and an intuitive graphical LCD interface for daily business telephony.

It supports dual standard telephony protocols: industry-standard RFC 3261-compliant SIP v2 for full interoperability with third-party hosted PBX, Asterisk, Broadsoft VoIP platforms, plus Cisco proprietary SPCP (Smart Phone Control Protocol) for seamless integration with Cisco UC500 Series unified communication gateways and SPA9000 voice systems. The entire SPA500 series reached End-of-Sale (EoS) on June 1, 2020, with End-of-Support (EoS) ending May 31, 2025; it is classified as legacy discontinued VoIP hardware, succeeded by Cisco 7800/8800 enterprise IP phone series and modern Webex Calling endpointsCisco.

All device configuration management, dial plan editing, unattended bulk firmware upgrades and remote diagnostics are supported via secure auto-provisioning over TFTP, HTTP and HTTPS. An embedded web administration server provides full granular device configuration access, with separate administrator and standard user password permission tiers to prevent unauthorized system modification. Users can also configure basic settings directly via on-device LCD menu navigation without a PC web portalCisco.

A scalable expansion feature of the SPA504G is compatibility with up to two Cisco SPA500S expansion modules, adding up to 64 programmable speed dial and line monitoring keys for receptionists or staff requiring extensive extension visibility and quick dial accessCisco.

Hardware, Display & Audio Architecture

1. Four Independent Dedicated Call Lines

Supports up to four separate SIP registrations, with full per-line call state handling including call waiting, hold, line status visual indicators and shared line appearance capabilities across distributed locations.

2. Graphical LCD Display & Physical Control Layout

• Display Panel: 128 × 64 pixel backlit monochrome graphical LCD screen, supporting caller ID name/number display, real-time call duration timestamps, local call history logs, system menu navigation, network time/date and customizable startup station identity text displayCisco.
• Hard Keys & Navigation Controls: Standard 12-key tactile numeric dial pad; dedicated illuminated function hard keys for Mute, Headset, Speakerphone, Hold, Voicemail retrieval and Settings menu access; four-way directional navigation rocker with central select button for LCD menu browsing; universal volume control rocker to independently adjust handset, headset, speakerphone and ringtone audio levels.
• LED Status Indicators: Illuminated status LEDs on all dedicated audio function keys; standalone red Message Waiting Indicator (VMWI) LED to alert users of unread voicemail messages; built-in LED diagnostic test function for on-site hardware troubleshootingCisco.

3. Complete HD Wideband Audio Subsystem

• Ergonomic analog wired handset with native G.722 HD wideband audio support for natural, clear voice transmission and reception.
• Built-in full-duplex hands-free speakerphone with acoustic echo cancellation, supporting simultaneous talk/listen conference calling without audio cut-off.
• Standard 2.5mm TRS headset audio jack for compatibility with mainstream office wired headsets.
• Supported Voice Codecs: G.711 A/µ law, G.726, G.729AB, G.722 HD wideband voiceCisco.
• Audio Optimization Technologies: Adaptive dynamic jitter buffer, voice frame loss concealment, Voice Activity Detection (VAD) silence suppression, Comfort Noise Generation (CNG); DTMF transmission supported via in-band audio or RFC 2833 out-of-band SIP INFO signalingCisco.

4. Chassis & Mounting Specifications

Compact matte silver/black ABS plastic desktop chassis with integrated foldable rear support stand for stable desk/countertop placement. Wall-mount bracket accessories are sold separately and not included in standard SPA504G factory packaging.

• Physical Dimensions (W × H × D): 214 × 212 × 44 mm
• Unit Weight: 0.9 kg (2.0 lbs)

Network, Power & Hardware Interfaces

1. Dual Switched 10/100BASE-TX Ethernet Ports

Two auto-sensing RJ45 LAN ports with integrated mini Ethernet switch, a core feature for standard office workstation deployments:

• Primary WAN Port: Connects the IP phone to corporate LAN switches or VoIP gateways for SIP signaling and RTP voice media traffic.
• Secondary PC Pass-Through Port: Enables direct connection of desktop PCs, laptops or retail POS terminals to the office network through the phone, eliminating the need for extra wall Ethernet jacks and reducing cabling infrastructure costsCisco.

Supported networking standards: Full IPv4 RFC compliance suite, DHCP client, DNS A/SRV resource records, ARP, ICMP, TCP/UDP, RTP/RTCP voice quality reporting, DiffServ QoS traffic marking, IEEE 802.1p / 802.1Q Layer 2 VLAN traffic prioritization, STUN NAT traversal for remote/home office NAT network environments, SNTP network time synchronization, CDP and LLDP network device discovery protocolsCisco.

2. Power Supply Specifications

• Primary Power: Native IEEE 802.3af Class 3 PoE support; draws electrical power directly from PoE-enabled network switches via Ethernet cable, eliminating separate AC power adapters for standard deployments.
• Optional Auxiliary Power: Separate universal 100–240V AC switching power adapter (Cisco PA100 series, sold separately) with +5 VDC / 2.0A maximum output for non-PoE network environments.

3. Additional Physical Interfaces

• RJ-9 modular wired handset connector
• 2.5mm TRS headset audio jack
• Recessed pinhole password-protected factory reset button to block unauthorized full configuration erasure

Core Business Telephony Feature Set

All calling functions can be configured via the embedded web GUI, on-device LCD menu or triggered through standard SIP star feature codes:

1. Four-Line Call Handling: Per-line call waiting, call hold, music-on-hold, attended & blind call transfer, local three-way audio conferencing, call swap between active lines, automatic last number redial, on-hook dialing, global do-not-disturb (DND) silence mode, call park and unpark functionality, shared line appearance support.
2. Caller ID & Personalization: Caller ID name/number display on LCD screen, outbound caller ID blocking, anonymous call rejection, distinctive selective ringtones configurable per line, support for 8 programmable speed dial entries and a local personal phone book stored persistently on the device; up to 10 user-downloadable custom ring tonesCisco.
3. Group & Utility Calling: One-touch intercom internal calling, selective and group call pickup, call back on busy, system group paging support.
4. Local Call Log Storage: On-device storage for 60 entries each of dialed, received and missed call records with timestamps and call duration data, viewable directly on the LCD screen or embedded web management portal.
5. Voicemail Integration: Native VMWI voicemail notification via SIP SUBSCRIBE/NOTIFY messaging, dedicated one-touch voicemail retrieval hard key.

Security & Remote Management Capabilities

1. Encrypted Voice Communications: SRTP (Secure Real-time Transport Protocol) up to 256-bit AES encryption for VoIP audio media streams, TLS encrypted SIP signaling traffic to block network eavesdropping and malicious signaling interception.
2. Multi-Tier Device Access Security: Dual-level password protection separating administrator full configuration rights and limited standard user access; HTTPS encrypted web management with factory pre-installed digital client certificates; MD5 HTTP Digest authentication for remote provisioning servers; password-locked factory reset function to prevent unauthorized full configuration wipe.
3. Automated Provisioning & System Monitoring: Secure unattended remote firmware upgrades without interrupting active voice calls, centralized syslog event logging, real-time call performance metric reporting, built-in network diagnostic tools for service providers and on-site IT administrators; configurable per-line event logging and RTCP-XR voice quality statistics reporting.

Environmental & Regulatory Specifications

• Regulatory Compliance Certifications: FCC Part 15 Class B electromagnetic compatibility, UL electrical safety certification, CE marking for European Union market compliance, A-Tick Australian telecommunications equipment compliance standard, HAC hearing aid compatibility certificationCisco.
• Operating Environment: Indoor use only Operating Temperature: 0°C ~ +40°C (32°F ~ 113°F) Storage Temperature: -20°C ~ +70°C (-13°F ~ 185°F) Operating Humidity: 5% – 95% non-condensing Storage Humidity: 5% – 95% non-condensing
• Memory Architecture: Onboard flash memory for persistent firmware and configuration storage, dedicated SDRAM runtime memory for real-time multi-line call processing and embedded web server operation.
• Lifecycle Status: Discontinued End-of-Sale legacy small business VoIP hardware, fully replaced by modern enterprise IP telephony endpoints.
• Warranty: Standard Cisco limited hardware warranty for small business end users.

Key Specification Bullet Points

• Model Number: Cisco SPA504G
• Device Type: Small Business 4-Line LCD SIP/SPCP VoIP Desk IP Phone with 802.3af PoE
• Supported Telephony Protocols: SIP v2 (Full RFC 3261 Standard Suite), SPCP (Cisco Smart Phone Control Protocol for UC500 Series Gateways)
• Supported Voice Codecs: G.711 A/µ, G.726, G.729AB, G.722 HD Wideband Voice
• Display: 128 × 64 Backlit Monochrome Graphical LCD Screen with caller ID and call log display
• Physical Buttons & Indicators: 12-key numeric dial pad, dedicated illuminated hard keys for Mute, Headset, Speakerphone, Hold, Voicemail, Settings; four-way navigation rocker; volume control rocker; standalone red VMWI voicemail waiting LED
• Physical Audio Interfaces: RJ-9 handset port, 2.5mm headset jack, built-in full-duplex echo-canceling HD speakerphone
• Ethernet Interfaces: Dual auto-sensing 10/100BASE-TX RJ45 switched LAN ports (WAN uplink + PC pass-through secondary port)
• Power: Native IEEE 802.3af PoE support; optional separate 5V DC PA100 series power adapter sold separately
• Expansion Compatibility: Supports up to two SPA500S attendant console modules for additional programmable line monitoring and speed dial keys
• Mounting Method: Desktop foldable stand as standard; wall-mount hardware sold separately
• Supported QoS & Networking: DiffServ marking, 802.1p/802.1Q VLAN tagging, STUN NAT traversal, SNTP time sync, CDP/LLDP network discovery
• Security Features: TLS encrypted SIP signaling, SRTP up to 256-bit AES encrypted voice media, dual-level admin/user password lock, HTTPS web management, password-protected factory reset
• Core Call Features: 4-line concurrent call support, call waiting, hold, attended/blind transfer, three-way conference, caller ID blocking, anonymous call rejection, intercom, group call pickup, speed dial, local LCD-accessible call logs, DND silent mode, voicemail VMWI notification, call park/unpark, shared line appearance
• Management Tools: Embedded web admin interface, on-device LCD menu configuration, TFTP/HTTP/HTTPS auto remote provisioning, syslog logging, remote unattended in-service firmware upgrades, RTCP-XR voice quality reporting
• Deployment Scenarios: Office manager workstations, small business front reception desks, retail supervisor workstations, multi-line administrative staff desks, medium-volume small business voice deployments
• Lifecycle Status: Discontinued End-of-Sale legacy VoIP phone
• Warranty: Cisco standard limited hardware warranty

Model Quick Reference

• The SPA504G is the mid-tier four-line LCD model of the SPA500 series, positioned between the single-line SPA502G and eight-line SPA508G. It is distinguished by four independent SIP registration lines, graphical backlit LCD display and native PoE supportCisco.
• Primary deployment advantage: Native IEEE 802.3af PoE power support and dual Ethernet pass-through ports eliminate redundant wall network jacks for combined PC + phone workstation setups, reducing cabling infrastructure costs for mass small business rollouts.
• Unique scalability: Compatible with up to two SPA500S expansion modules for receptionists requiring multi-line monitoring and bulk speed dial functionality.
• Compatible with all standard SIP hosted PBX platforms and Cisco UC500 unified communications gateways via dual SIP/SPCP protocol support.