# Telecommunications — Genyra > Enterprise phone systems: on-premises or private-hosted PBX, SIP trunking, encrypted calls, mobile policy and the call inside the workflow, operated openly. Canonical page: https://genyra.com/infrastructure/telecommunications PBX systems, SIP trunking, enterprise privacy and mobile solutions for organisations whose calls are part of the record: designed, documented and operated the way the rest of the estate is. ## A PBX that belongs to the organisation. The telephone system runs on-premises or in a private-hosted environment the organisation controls. Extensions, call routing, hunt groups, voicemail and business-hours rules are configured as a record that can be read, reviewed and restored, not as settings someone once clicked through. The PBX is integrated with the directory the organisation already keeps, so an extension follows a person and a role rather than a desk, and with the CRM or case system, so a call is matched to a customer before it is answered. - Extensions, hunt groups and voicemail held as configuration - Routing rules written down before they are applied - The directory as the source of who holds which extension - CRM and case-system integration for caller matching ## SIP trunking and interconnect. Calls reach the public network over SIP trunks. Which codecs are offered, how number ranges are assigned and presented, and how calls fail over between trunks are decided per installation and recorded with the design, so the second trunk is a planned path and not a hope. Call quality is measured, not assumed. Latency, jitter and packet loss are monitored per trunk and per route, so a complaint about a bad line can be traced to a time, a path and a cause. ## Privacy and the record of a call. Signalling and media are encrypted where the trunk, the handset and the softphone support it, and the exceptions are listed rather than left to be discovered. Telephony is segregated from the user network, so a compromised workstation is not a route to the voice system and a telephone is not a route to the file server. Call recording happens only where it is authorised, and retention is a decision the organisation makes and writes down: how long, who may listen, and the record of every time someone did. Whether a recording is subject to legal hold, which conversations may be recorded at all, and what a caller must be told are questions for the organisation and its advisers to decide before the first recording is kept. The system is built to carry those decisions, not to make them. - Encrypted signalling and media where supported, exceptions listed - Telephony segregated from the user network - Recording only where authorised; retention as a written decision - Who may listen, and a record of each time they did ## Mobile solutions as policy, not improvisation. SIM allocation and device management are written as policy: who is issued what, what the device may reach, and what happens when it is lost. Softphones and mobile extensions reach the PBX over a private link rather than the open internet, so a staff member on a mobile is on the same system, with the same routing and the same record, as a colleague at a desk. Mobile device management keeps work and personal use separate on the same handset, and secure messaging for staff is set up on the organisation’s own terms, with the same questions asked about retention and access as for voice. ## The call inside the workflow. A call is not finished when the handset goes down. The agent sees the customer’s record as the call arrives, the call record is written into the case system with its duration, outcome and any authorised recording reference, and a callback is scheduled as a task with an owner rather than a note on a pad. The contact centre and the case system hold one account of what was said and what was agreed. ## Operate it in the open. The PBX, the trunks and the links between them are monitored, and every change is proposed, scheduled into a declared window, applied and recorded. Number porting is treated as a planned change with a rehearsal and a rollback, because a number that stops ringing is an outage whatever the cause. Resilience is designed for the failures that actually happen: a trunk that drops, a site that loses power, a provider that changes a setting. ## How an engagement starts. Bring a description of the sites, the number ranges, the current telephone system and the systems a call must reach, together with any recording, retention or regulatory constraints already known. We review what is there, propose the PBX, trunks, privacy controls and integrations, and agree who operates the result. Equipment, trunks and mobile services are specified for the particular organisation and confirmed in a proposal, not assumed. ## Questions we are asked **Do you supply the PBX?** We design, build and operate a PBX the organisation controls, on-premises or in a private-hosted environment, configured as a record that can be read and reviewed. **Can we keep our telephone numbers?** Number porting is treated as a planned change with a rehearsal and a rollback, scheduled into a declared window rather than attempted on the day. **Are calls encrypted?** Signalling and media are encrypted where the trunk, the handset and the softphone support it. The exceptions are listed in the design rather than left to be discovered. **What is an enterprise phone system?** A PBX the organisation controls, reached over SIP trunks, with extensions, routing, recording and mobile policy configured as a record, segregated from the user network and connected to the systems a call must reach. ## Related work - [Networking](https://genyra.com/infrastructure/networking): Enterprise network design, IP address management, private connectivity between sites and clouds, edge protection and operator access, operated as a record. - [Private environments](https://genyra.com/infrastructure/private-environments): Private cloud architecture and security for applications and data that need deliberate placement: public vs private cloud, isolation, access and administration. - [Secure environments](https://genyra.com/solutions/secure-environments): Secure environment engineering for access, deployment, secrets, isolation, logging and recoverable operations. Contact: contact@genyra.com Genyra LLC and the Dubai business Genyra L.L.C-FZ / Genyra.ai are distinct entities. Project scope and the contracting entity are agreed explicitly.