Cisco CP-6921-K9 Full English Product Description

Listing Title

Cisco CP-6921-K9 Unified Two-Line IP Desk Phone (Dual SCCP/SIP Protocol), Backlit Monochrome 396×81 LCD Display, Dual 10/100 Fast Ethernet Switched Ports with PC Pass-Through, IEEE 802.3af Class 1 PoE Powered, Full-Duplex Echo-Canceling Speakerphone, Dedicated Hold / Transfer / Conference Hard Keys, RJ9 Analog Headset Port, HAC Hearing-Aid Compatible Handset, Energy-Saving Deep Sleep Mode, Recyclable Eco-Friendly ABS Chassis, Charcoal Black Standard Handset Base Model, Desktop Two-Position Adjustable Stand or Wall Mountable, Ideal for General Office Staff, Small Business Workstations, Clinic Desks, Retail Administrative Back Offices and Mid-Traffic Two-Line Business VoIP Deployments

Full Commercial Overview

The Cisco CP-6921-K9 belongs to the Cisco Unified IP Phone 6900 Series, a cost-effective mid-tier business VoIP endpoint designed for everyday office users requiring multi-call handling and visual LCD call status feedbackCisco. It natively supports dual telephony protocols: proprietary SCCP (Skinny Client Control Protocol) for Cisco Unified Communications Manager (CUCM) / UCME, and open SIP v2 for interoperability with third-party SIP PBX and UCaaS platforms.

As the upgraded successor to the LCD-less CP-6911, the CP-6921 adds a backlit monochrome graphical LCD screen for Caller ID, directory browsing, call log viewing and XML application rendering. It supports two independent directory numbers (DNs), with multi-call-per-line functionality allowing multiple concurrent calls on each line.

Multiple variant SKUs are available for flexible deployment customization:

1. CP-6921-K9: Base charcoal black chassis with standard curved handset
2. CP-6921-W-K9: Arctic white chassis variant for bright office interiors
3. CP-6921-CL-K9: Charcoal black chassis with slimline lightweight compact handset

The phone integrates eco-conscious design elements, including reground recyclable polycarbonate ABS plastic construction and a configurable Deep Sleep power-saving mode that cuts idle power consumption by up to 50% during off-hours to reduce energy costs. Global localization support includes multi-language menus and right-to-left text rendering for international enterprise deploymentsCisco.

All configuration, mass remote provisioning and unattended bulk firmware upgrades are managed via TFTP/HTTP/HTTPS secure auto-provisioning servers and an embedded HTTPS web administration portal, with centralized monitoring compatible with CUCM and third-party SIP PBX management platformsCisco.

Hardware & Physical Design Architecture

1. Ergonomic Chassis & Flexible Mounting Options

• Form factor: Low-profile desktop body equipped with a two-position adjustable foldable foot stand for optimized viewing angles. The foot stand is fully removable to enable direct wall mounting without extra wall-mount accessory kits, with standardized pre-drilled mounting holes on the rear panel.
• Chassis material: Reground recyclable polycarbonate ABS plastic; base CP-6921-K9 ships in matte charcoal black finish.
• Handset variants: Standard ergonomic coiled handset included as default; slimline lightweight handset available via separate SKU CP-6921-CL-K9.
• Physical Dimensions (H × W × D, excluding handset): Standard chassis footprint consistent with the 6900 series form factor
• Unit Weight: Standard handset version 1031g (36 oz); slimline handset variant 940g (33 oz)
• Operating Environment (Indoor Only): Operating Temperature: 0°C ~ +40°C (32°F ~ 104°F) Storage Temperature: -10°C ~ +60°C (14°F ~ 140°F) Operating Humidity: 10% – 95% non-condensing

2. Key Layout, LCD Display & Control Hardware

The CP-6921 features a backlit monochrome graphical LCD screen for visual call management, paired with dedicated fixed function hard keys for core call workflows:

1. Backlit monochrome LCD display: 396 × 81 pixel resolution, anti-glare surface, adjustable brightness, multi-language and right-to-left text support; displays Caller ID, call timers, local directory, call logs, XML enterprise applications, line status and voicemail alerts.
2. Two tricolor LED illuminated line keys: Visual state signaling (solid green = idle line; solid red = active/held call; flashing red = incoming ringing call)
3. Three dedicated one-touch fixed function hard keys: Hold, Transfer, Conference for instant call control without menu navigation
4. Standard 12-key tactile numeric dial pad (0–9, *, #)
5. Four context-sensitive softkeys positioned below the LCD screen, dynamically mapped to on-screen menu options
6. Central five-way navigation rocker with select button for scrolling menus, directories and call logs
7. Auxiliary dedicated hard keys: Mute, Headset, Volume Up/Down, Redial, End Call
8. Vertical red Message Waiting Indicator (MWI) LED on the top edge of the chassis to alert users of unheard voicemail messages

3. Premium HD Audio Subsystem & Supported Codecs

• Ergonomic analog handset with noise isolation receiver, certified HAC (Hearing-Aid Compatible) to meet accessibility standards for users with hearing assistive devices.
• Built-in full-duplex echo-canceling hands-free speakerphone for conference calls and hands-free communication (major upgrade over the ringtone-only speaker on CP-6901)
• RJ9 modular analog headset port for connecting third-party wired office headsets
• Supported voice audio encode/decode codecs: G.711a / G.711u, G.729a, G.729ab, iLBC low-bitrate codec
• Voice quality optimisation features: Voice Activity Detection (VAD), Comfort Noise Generation (CNG) to eliminate silent line background noise during idle calls

Network, Power & Hardware Interfaces

1. Dual 10/100BASE-TX Fast Ethernet Switched RJ45 Ports

Two auto-sensing Fast Ethernet ports with integrated mini network switch, eliminating the need for separate wall jacks for desk PCs:

• Primary WAN Network Port: Connects the IP phone to corporate LAN switches, VoIP gateways or SIP PBX appliances for SIP/SCCP control signaling and RTP voice media traffic
• Secondary PC Pass-Through Port: Enables direct connection of desktop PCs, laptops or POS terminals to the corporate network through the phone

Supported networking standards: IPv4 addressing (DHCP dynamic IP assignment or static manual IP configuration), Cisco Discovery Protocol (CDP), LLDP-MED device discovery, 802.1Q voice VLAN tagging, 802.1p Layer 2 QoS traffic prioritization, STUN NAT traversal, SNTP network time synchronization.

2. Dual Power Supply Options (Class 1 PoE Primary Power)

1. Native IEEE 802.3af Class 1 Power over Ethernet support (primary power source): Maximum typical power consumption: Low energy draw optimized for continuous operation; configurable Deep Sleep mode reduces idle power usage by up to 50% during off-hours. Input rating: 48V DC PoE input from compliant PoE network switches
2. Optional external 48V DC universal AC-to-DC power cube (sold separately, part number CP-PWR-CUBE-3=) for non-PoE network environmentsCisco.

3. Rear Panel Physical Interfaces

1. RJ9 modular handset jack for connecting coiled handset cord
2. Dual RJ45 10/100 Fast Ethernet PoE switched ports (Network + PC pass-through)
3. RJ9 analog headset port
4. DC 48V auxiliary power input jack for optional external power adapter
5. Recessed pinhole password-protected factory reset button to restore all device configuration to factory default values

Core Telephony Feature Set

All calling and configuration functions are provisioned via CUCM / third-party SIP PBX auto-provisioning templates; routine operations are triggered via dedicated physical hard keys or LCD softkey navigation:

1. Two-Line Multi-Call Handling Supports two independent directory number (DN) line registrations with multi-call-per-line appearance, enabling multiple concurrent active calls per line. Dedicated Hold key for call park, dedicated Transfer and Conference hard keys for one-touch consultation transfer and three-way ad-hoc audio conference calls. Supports call swap between multiple active calls, automatic last-number redial via dedicated Redial key.
2. Caller ID & Personalization Features Visual Caller ID name/number displayed on the backlit LCD screen; adjustable ringtone volume and multiple selectable ringtone tones, customizable unique ring alert patterns per line. On-device local directory storage with search functionality, plus XML framework support for corporate LDAP directory lookup.
3. Utility Workplace Calling Functions One-touch redial, mute for confidential conversations, headset mode toggle, shared line appearance monitoring support for multi-user shared reception lines, call forward, call park and call pickup functionality, intercom auto-answer calling for internal staff communication.
4. Local Call Log Storage Onboard persistent storage for dialed outgoing calls, received answered calls and missed incoming calls, complete with timestamp, call duration and full Caller ID details; all logs fully viewable directly on the phone’s LCD screen or embedded web management portal.
5. Voicemail MWI Integration Native Message Waiting Indicator (MWI) notification via SIP/SCCP SUBSCRIBE/NOTIFY messaging; steady red chassis LED illumination plus on-screen LCD pop-up alerts to notify users of unheard voicemail messages.
6. Supported Security Call Features Anonymous incoming call rejection, outbound caller ID blocking via server-side configuration, encrypted SIP/SCCP call control signaling (TLS) and encrypted voice media streams (SRTP) for enterprise secure communications deployments.

Security & Remote Device Management Capabilities

1. End-to-End Encrypted Communications TLS transport layer encryption for SCCP/SIP call control signaling; SRTP AES encrypted RTP voice media streams to prevent call audio interception on shared office LAN networks.
2. Multi-Tier Access Permission Controls Separate administrator and end-user access privilege levels protected by unique authentication passwords; password-locked factory reset function to block unauthorized wiping of device configuration and line registration data.
3. Centralized Auto-Provisioning & Firmware Upgrades Unattended remote bulk firmware upgrades via TFTP/HTTP/HTTPS secure auto-provisioning servers, fully compatible with CUCM and third-party SIP PBX platforms. Embedded HTTPS web-based administration interface for local device configuration and real-time status monitoringCisco.
4. System Monitoring & Diagnostics Real-time device status tracking via CUCM / SIP PBX management consoles, including online/offline connectivity status, line registration state, active call session auditing and centralized syslog event logging for network telephony audit trails.

Environmental & Regulatory Compliance Certifications

• Regulatory EMI/EMC: FCC Part 15 Class B electromagnetic interference compliance, CE marking for European Union markets, ICES-003 Class B certification
• Safety certifications: UL / C-UL 60950 electrical safety certification, EN 60950 IEC global electrical safety standard
• Telecom regulatory approvals: FCC Part 68 telecom terminal device certification, TIA 810A HAC hearing aid compatibility standard
• Memory architecture: 8MB flash memory for persistent firmware and configuration storage; 32MB SDRAM runtime memory for SCCP/SIP call processing, LCD rendering and network stack operation
• Lifecycle Status: Discontinued End-of-Sale legacy Cisco Unified IP Phone 6900 Series hardware, limited critical security bug maintenance support only with no new feature firmware development
• Warranty: Standard one-year limited Cisco hardware warranty for commercial business end-user deployments

Key Specification Bullet Points

• Model Number: Cisco CP-6921-K9 (Charcoal Black Standard Handset); CP-6921-W-K9 (White Chassis); CP-6921-CL-K9 (Slimline Lightweight Handset Variant)
• Device Type: Mid-Tier Two-Line Unified IP VoIP Desk Phone (Dual Native SCCP / SIP Dual Protocol), Backlit Monochrome LCD Display, Dual Switched Fast Ethernet Ports with PC Pass-Through
• Supported Telephony Protocols: SCCP (Skinny Client Control Protocol) for Cisco CUCM / UCME; SIP v2 open standard for third-party SIP PBX / UCaaS platforms
• Supported Voice Audio Codecs: G.711a / G.711u, G.729a, G.729ab, iLBC Low Bitrate Codec
• Display: Backlit Monochrome LCD Screen, 396 × 81 Pixel Resolution, Anti-Glare Surface, Multi-Language & Right-to-Left Text Support
• Fixed Hardware Function Keys: Dedicated Hold, Redial, Transfer, Conference, Mute, Headset Hard Keys; Four Dynamic LCD Softkeys, Five-Way Navigation Rocker
• Audio Features: HAC Hearing-Aid Compatible Handset Receiver, Full-Duplex Echo-Canceling Hands-Free Speakerphone, VAD Voice Activity Detection, CNG Comfort Noise Generation, RJ9 Analog Headset Port
• Physical Interfaces: 1 x RJ9 Handset Port, Dual 10/100BASE-TX RJ45 Fast Ethernet Switched PoE Ports (Network + PC Pass-Through), RJ9 Headset Jack, 48V DC Aux Power Input Jack, Password-Protected Factory Reset Pinhole
• Power Specifications: IEEE 802.3af Class 1 PoE Primary Power, Configurable Deep Sleep Energy-Saving Mode; Optional Separate 48V DC Universal AC Power Cube (Sold Separately)
• Mounting Method: Two-position adjustable removable foldable desktop foot stand as standard; Wall mountable without additional wall mount kit via rear pre-drilled holes
• Supported QoS & Networking Features: IPv4 DHCP/Static IP Assignment, CDP/LLDP-MED Device Discovery, 802.1Q Voice VLAN Tagging, 802.1p Layer 2 QoS Prioritization, STUN NAT Traversal, SNTP Network Time Synchronization
• Security Features: TLS Encrypted SCCP/SIP Call Signaling, SRTP AES Encrypted Voice Media Streams, Dual-Level Admin/User Password Access Control, Password-Locked Factory Reset, Embedded HTTPS Web Administration Interface
• Core Telephony Call Features: Two Independent SIP/SCCP Line Registrations, Multi-Call-Per-Line Appearance, Supports Multiple Concurrent Calls + Call Waiting, Dedicated Hold / Redial / Transfer / Conference Hard Keys, Full-Duplex Hands-Free Speakerphone, Visual LCD Caller ID Display, MWI Voicemail Message Waiting LED Alert, Anonymous Call Rejection, Outbound Caller ID Blocking, Shared Line Appearance Support, Call Forward, Call Park & Call Pickup, Local Call Log Storage, XML LDAP Corporate Directory Lookup
• Management Tools: TFTP/HTTP/HTTPS Secure Remote Auto-Provisioning, Unattended Bulk Remote Firmware Upgrades, Embedded Web-Based Local Admin Portal, CUCM / Third-Party SIP PBX Centralized Device Monitoring, Syslog Event Logging & Built-In Network Diagnostics
• Target Deployment Scenarios: General small and medium business administrative staff desks, retail back-office workstations, clinic and dental practice reception counters, mid-traffic two-line office voice deployments, hotel auxiliary staff phones, all routine business VoIP environments requiring visual LCD call management, dedicated transfer/conference keys and PC daisy-chaining capability
• Lifecycle Status: Discontinued End-of-Sale legacy Cisco Unified IP Phone 6900 Series hardware
• Warranty: One-year limited Cisco hardware warranty

Model Quick Reference

• CP-6921-K9 is the base charcoal black two-line mid-tier IP phone of Cisco Unified IP Phone 6900 Series, supporting dual SCCP/CUCM and open SIP third-party PBX protocols, designed for daily office users requiring visual LCD call status feedback.
• Core positioning: Cost-effective two-line business VoIP endpoint with backlit graphical LCD display, differentiated from the LCD-less CP-6911 model by visual Caller ID, directory and call log viewing capabilities, while retaining dual Fast Ethernet PC pass-through switch and dedicated physical Transfer/Conference hard keys.
• Key internal series differentiation vs other 6900 series models:
  1. CP-6901: Single line, no LCD display, no dedicated Transfer/Conference keys (operated via handset hookswitch), ringtone-only speaker (no full-duplex speakerphone)
  2. CP-6911: Single line, no LCD display, dual Fast Ethernet PC pass-through switch, dedicated Transfer/Conference hard keys, full-duplex speakerphone
  3. CP-6921: Two independent multi-call lines, backlit monochrome graphical LCD display, dual Fast Ethernet PC pass-through switch, dedicated Transfer/Conference hard keys, full-duplex speakerphone, multi-language XML application support
• Primary deployment advantage: Balanced cost and functionality for everyday office staff, combining visual LCD call management, two-line multi-call handling, dual Fast Ethernet switch eliminating extra wall jacks for office PCs, dedicated call control hard keys simplifying routine transfer/conference workflows, energy-efficient PoE operation with Deep Sleep power saving mode and flexible desktop/wall mounting for widespread small-business deployments.