DP-9851-K9 – 3.7-in Color Display – 6 Line Keys with 46-Line Cap – PoE Class 3 Desk Phone
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DP-9851-K9 Description
The DP-9851-K9 is a Cisco Desk Phone 9851, the mid-range model of the Desk Phone 9800 Series, for knowledge-worker desks that need a color screen and more line keys. The phone has a 3.7-inch backlit color LCD at 480 x 240, 6 physical line keys with a capacity of 46 lines and programmable keys, a 2-port 10/100/1000BASE-T switch, one USB-A and one USB-C port, and IEEE 802.3af/at PoE Class 3 power. The phone has no Wi-Fi or Bluetooth radio and supports one 9800 Key Expansion Module.
Quick Specs
|
Parameter |
Specification |
|---|---|
|
Product ID |
DP-9851-K9 |
|
Display |
3.7-inch backlit color LCD, 480 x 240 |
|
Line keys |
6 physical line keys, up to 46 lines and programmable keys |
|
Ethernet |
Internal 2-port 10/100/1000BASE-T switch with RJ-45 PC pass-through |
|
Wireless |
No Wi-Fi or Bluetooth radio, wired endpoint |
|
USB port |
1x USB-A and 1x USB-C |
|
Key expansion |
Supports 1 Cisco Desk Phone 9800 Key Expansion Module (DP-9800-KEM=) |
|
Power |
PoE Class 3 (IEEE 802.3af/at); optional Cisco Power Adapter 3 |
|
Call platforms |
Cisco Unified CM, Webex Calling, Webex Dedicated Instance, Cisco BroadWorks, third-party SIP |
Application Scenarios
At unassigned desks in hybrid offices, staff sign in through Webex hot desking and pick up their own line, directory and calendar on the phone’s color display.
At desks with one LAN drop, the desktop PC plugs into the phone’s gigabit pass-through port while 802.1Q keeps voice and data on separate VLANs.
Across sites split between on-premises Unified Communications Manager clusters and Webex Calling or BroadWorks tenants, the phone registers to either, so one hardware model covers both.
Product Comparison
|
Parameter |
DP-9851-K9 | ||
|---|---|---|---|
|
Display |
3.7-inch backlit color LCD, 480 x 240 |
3.5-inch backlit grayscale LCD, 384 x 160 |
5-inch backlit color LCD, 800 x 480 |
|
Physical line keys |
6 |
4 |
10 |
|
Line and programmable key capacity |
46 |
4 |
130 |
|
Ethernet |
2-port 10/100/1000BASE-T |
2-port 10/100/1000BASE-T |
2-port 10/100/1000BASE-T |
|
Wi-Fi |
No Wi-Fi radio |
No Wi-Fi radio |
802.11a/b/g/n/ac, dual band |
|
Bluetooth |
No Bluetooth radio |
No Bluetooth radio |
5.2 |
|
USB port |
1x USB-A, 1x USB-C |
1x USB-A |
1x USB-A, 1x USB-C |
|
Key expansion |
1 Key Expansion Module |
Not supported |
1 on PoE Class 3; up to 3 on Cisco Power Adapter 3 |
|
Power over Ethernet |
IEEE 802.3af/at, Class 3 |
IEEE 802.3af/at, Class 2 |
IEEE 802.3af/at, Class 3 |
DP-9851-K9 is the 6-line color model: against DP-9841-K9 it adds a 3.7-inch color display, a USB-C port, 46-line capacity and support for one Key Expansion Module, at PoE Class 3 instead of Class 2. Desks that stay at 4 lines with no module can keep DP-9841-K9 on the lower PoE class. Desks that need Wi-Fi, Bluetooth, more than one module or up to 130 lines move to DP-9861-K9, which has 10 line keys and takes up to 3 modules on Cisco Power Adapter 3, while DP-9851-K9 stops at one module on either power source.
Ordering Checklist
- Power source: Add Cisco Power Adapter 3 in the regional PID, such as CP-PWR-ADPT-3-NA= or CP-PWR-ADPT-3-EU=, for desks without PoE Class 3. The phone does not ship with a power adapter.
- TAA or Customized build: Order DP-9851-K9++= or DP-9851NR-K9++= for TAA; DP-9851-K9–= or DP-9851NR-K9–= for Customized. These builds are separate PIDs from DP-9851-K9=.
- Key expansion module: Add DP-9800-KEM=, maximum 1 per phone, as a separate line item.
- Wall mount: Add DP-9800-WMK= for wall-mounted installs; the kit is a separate accessory.
Specifications
| Parameter | Specification | Parameter | Specification |
|---|---|---|---|
| Product ID | DP-9851-K9 | Cisco ordering ID | DP-9851-K9= |
| Phone software | Cisco PhoneOS | Color options | Carbon Black (DP-9851-K9); First Light (DP-9851-L-K9=) |
| Ordering variants | TAA-compliant DP-9851-K9++= / DP-9851NR-K9++=; Customized DP-9851-K9–= / DP-9851NR-K9–= | Call control platforms | Cisco Unified Communications Manager, Webex Calling, Webex Dedicated Instance, Cisco BroadWorks, third-party cloud calling platforms |
| Interoperability | Microsoft SIP Gateway compatible; Asterisk interoperability certified | Minimum Unified CM release | 12.5, with a device package required on some releases |
| Display | 3.7-inch backlit color LCD | Display resolution | 480 x 240 |
| Physical line keys | 6 | Programmable key capacity | 46 |
| SIP line capacity by platform | Capped at the phone’s 46-line capacity on Unified CM and Webex Dedicated Instance (platform maximum 130); up to 16 lines on Webex Calling and open SIP platforms | Line key pagination | Supported |
| Fixed keys | Calendar key; configurable Action button with up to 3 scenarios | Display customization | Custom wallpaper and logo |
| Handset | RJ-9 handset, hearing-aid compatible per FCC Part 68 and ADA | Speakerphone | Full-duplex hands-free speakerphone |
| Audio codecs | OPUS, G.722, G.722.2, iSAC, G.711 a-law/u-law, G.729a/b, iLBC | Calling features | Call waiting, hold/resume, music on hold, call forward, transfer, conference, speed dial, busy lamp field, call pickup, call park, hunt groups, shared lines, voicemail, E.911, intercom, call recording, Extension Mobility (varies by platform) |
| Webex integration | Unified call history and directory, hybrid calendar, one-button-to-join, Webex Companion, hot desking | Ethernet | Internal 2-port 10/100/1000BASE-T switch with RJ-45 PC pass-through |
| VLAN support | 802.1Q with separate voice and PC VLANs | Network features | SIP signaling, IPv4/IPv6, DHCP and static addressing, LLDP-MED, CDP, HTTPS, RTP/RTCP |
| Port authentication | 802.1X with EAP-FAST and EAP-TLS | USB ports | 1x USB-A (2.5W on PoE, 5W on local power); 1x USB-C (2.5W) |
| Key expansion | Supports 1 Cisco Desk Phone 9800 Key Expansion Module (DP-9800-KEM=) over USB-A | Power over Ethernet | IEEE 802.3af/at, Class 3 |
| Input rating | 0.42A 48V DC | Local power option | Cisco Power Adapter 3, ordered by region (CP-PWR-ADPT-3-NA=, -EU=, -UK=, -AU=, -CN=, -IN=, -KR=, -BZ=, -AR=) |
| Power saving | Deep sleep 0.27W on local power / 0.69W on PoE; display off 2.82W on local power / 2.69W on PoE | Energy efficiency | EnergyStar certified; EU Lot 6 and Lot 26 compliant |
| Security | Secure Boot, image authentication, SUDI, TLS 1.3 signaling encryption, SRTP media encryption, Security-Enhanced Linux, configurable minimum TLS version | Hardware security module | TPM 2.0 |
| Security compliance | FIPS 140-2 and 140-3; UCR 2013 | Language support | About 40 languages including English, Simplified and Traditional Chinese, French, German, Spanish, Japanese, Korean |
| Accessibility | Voice Feedback in English, French, Italian, German, Spanish; adjustable font size; ADA-compliant dial pad | Operating temperature | 0 to 40°C |
| Operating humidity | 10 to 90% noncondensing | Dimensions | 226.0 x 214.0 x 49.4 mm |
| Weight | 968 g | Wall-mount kit | DP-9800-WMK= |
| Spare handset | DP-9800-HS= | Handset cord | DP-9800-CORD= |
| Sustainability | More than 74% post-consumer recycled plastics; 100% recyclable packaging |
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Customer Reviews
Questions & Answers
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What role does DP-9851-K9 play?
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How many lines and physical keys does DP-9851-K9 support?
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Can DP-9851-K9 use a Cisco Desk Phone 9800 Key Expansion Module?
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Which wireless radios are built into DP-9851-K9?
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How does DP-9851-K9 differ from DP-9841-K9?
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Which platform limit can reduce DP-9851-K9 below 46 lines?
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What USB interfaces does DP-9851-K9 provide?
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When is DP-9861-K9 a better fit than DP-9851-K9?
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