Grandstream GXP2135
Specifications
Calling
- SIP accounts / lines
- 4
- Programmable keys
- 32
- Local conference participants
- 4
Display
- Display size
- 2.8 in
- Display resolution
- 320 x 240
- Colour display
- Yes
Connectivity
- Ethernet
- Gigabit
- Power over Ethernet
- Yes
- Bluetooth
- Built in
Accessories
- Headset interfaces
- EHS, RJ9
Physical
- Wall mountable
- Yes
Audio
- HD voice
- Yes
- Full-duplex speakerphone
- Yes
Security
- TLS signalling
- Yes
- SRTP media encryption
- Yes
Compatible phone systems
The indicator shows whether a compatible configuration path is documented, or whether the result still needs verification. A not-listed result does not mean technically incompatible. It does not replace checking the provider firmware branch, tenant, network and feature requirements.
3CX V20Needs verification
Listed firmware applies to 3CX V20. Cloud or remote phones need a router phone or SBC. Recheck the current provider release before deployment.
Needs verification Not on reviewed list
Evidence reviewed: 2026-09-11
Sources and scope
Grandstream GXP2135. Current provider lists only. Not listed does not establish technical incompatibility. Historical 3CX V18 firmware and configuration material is not treated as current V20 support. Regional availability, hardware revisions and accessories remain unverified. No tenant or device was tested.
- 3CX V20 phone firmware
V20 scope statement and complete Phone Firmware table; no Grandstream or GXP row
Zoom PhoneNeeds verification
Yealink phones require Zoom-specific firmware. A certification entry does not confirm every feature or regional deployment.
Needs verification Not on reviewed list
Evidence reviewed: 2026-09-11
Sources and scope
Grandstream GXP2135. Current provider lists only. Not listed does not establish technical incompatibility. Historical 3CX V18 firmware and configuration material is not treated as current V20 support. Regional availability, hardware revisions and accessories remain unverified. No tenant or device was tested.
- Zoom Phone certified hardware
Desk phones > Grandstream exact-model table; the GXP model is absent; the page directs owners of unlisted models to Grandstream if assisted provisioning fails
Microsoft Teams SIP GatewayNeeds verification
This is SIP Gateway compatibility, not native Teams-phone certification. Use the gateway provisioning path and approved firmware; confirm tenant licensing, policies and network requirements.
Needs verification Not on reviewed list
Evidence reviewed: 2026-09-11
Sources and scope
Grandstream GXP2135. Current provider lists only. Not listed does not establish technical incompatibility. Historical 3CX V18 firmware and configuration material is not treated as current V20 support. Regional availability, hardware revisions and accessories remain unverified. No tenant or device was tested.
- Microsoft Teams SIP Gateway plan
Compatible devices table; no Grandstream vendor or GXP model row