Your PBX. Your building.
Our brains.
A Grandstream appliance that lives on site, for the businesses that want the phone system in their own building — with TCSS handling the trunking, provisioning, and support behind it.
You own the hardware · TCSS-managed option · No monthly per-seat fee
Grandstream UCM6202 / UCM6204 — Grandstream Certified Reseller.
Who it's for
When the box belongs on site
On-Prem fits a specific need well — here's when it's the right call.
Data-sovereignty needs
Call data and voicemail stay on hardware inside your own building, not a third-party cloud — the box is yours.
Existing infrastructure
Already invested in on-site networking, or an office that expects a phone closet? Slot the appliance right in.
No monthly per-seat math
Own the hardware once instead of renting a seat forever. Predictable capital cost instead of a growing per-user line item.
What TCSS adds
More than a box you bought online
Buying a Grandstream appliance is easy. Getting it provisioned, trunked, and supported is the part TCSS does.
The hardware, owned outright
A Grandstream UCM appliance, configured for your extensions and trunks — yours, not leased.
TCSS-managed option
Don't want to touch the box after install? We provision, patch, and monitor it remotely so it stays your system without becoming your job.
Carrier trunking, handled
We set up and support the SIP trunks so the appliance actually places and receives calls on day one.
Monitoring & support
We watch the box's health and back it with the same 24/7 US-based support behind every TCSS product.
The same web portal
Voicemail, call history, and usage in the same dashboard as Hosted PBX customers — no separate tool to learn.
Spec highlights
Grandstream UCM6202 / UCM6204
Published manufacturer specs, model-dependent.
| Model | Grandstream UCM6202 / UCM6204 |
| Max extensions | Up to 500 (model-dependent) |
| Max concurrent calls | Up to 60 (model-dependent) |
| Trunk support | SIP trunks, analog (FXO) ports on select models |
| Networking | Dual Gigabit LAN, integrated NAT router |
Source: Grandstream UCM6200 series published datasheet. Exact capacity varies by model and licensing — ask sales for the configuration that fits your seat count.
Not sure On-Prem is the fit?
Most businesses actually fit Hosted PBX better — no hardware to own at all. Want the control of on-site hardware with cloud reach and failover? That's Hybrid.
FAQ
Questions about On-Prem
No. Most customers choose the TCSS-managed option, where we provision and monitor the appliance remotely. You still own the box, but you're not the one patching it.
Want the phone system in your own building?
Talk to sales about a Grandstream appliance, sized and supported by TCSS.