Office telephone exchange: how to choose between cloud, IP, and analog exchange?
A telephone exchange is a system that distributes external lines to internal extensions within the office, routes calls, and records them. Today there are three options: cloud exchange where the provider's server is hosted externally, IP exchange installed on-site (IP PBX), and classic analog exchange that works with existing copper lines. The right choice depends on the office size, working method, and existing infrastructure.
Selection guide and FAQ
Comparison of three options
| Cloud Exchange | IP Exchange (on-site) | Analog Exchange | |
|---|---|---|---|
| Installation cost | Low — no hardware | Medium — server/device purchased | Low–Medium |
| Monthly expense | Subscription (per extension) | None (line fee only) | None (line fee only) |
| Remote/branch office operation | Optimal — extension available anywhere on the telephone | Available (with VPN/SIP) | Not available |
| If internet connection fails | Calls stop (GSM forwarding backed up) | Internal calls continue | Unaffected |
| Scalability | Adding extensions instant | License/port added | Card added, limited |
| Call recording, IVR, reporting | Included in package | Installed | Limited or none |
| Suitable for | Small–medium office, field work team, multiple branches | Organization requiring data security/customization | Existing analog line available, simple requirements |
Overlooked points in installation
- Your existing number is preserved: the same fixed number continues with number porting; business cards and signage remain unchanged.
- Your existing analog lines are not discarded — they connect to the IP PBX via FXO gateway, enabling gradual migration.
- IP phones are powered over the network (PoE switch); office cabling and switch capacity must be planned prior to the PBX.
- Audio quality depends on network stability rather than speed; voice traffic priority (QoS) is configured on the network.
- If call recording is to be maintained, the calling party must be informed that recording is taking place and access to recordings must be restricted (KVKK).
- Located in the same system room as your fire/security systems; uninterruptible power supply and grounding are addressed within the same project.
Fixed line, SIP line, and number assignment are services provided by electronic communications operators authorized by BTK. ASPEK is not the operator of this service; it undertakes the design, installation, integration to existing infrastructure, and maintenance of the PBX system, and provides the necessary technical guidance for obtaining the line from an authorized operator.
Frequently asked questions
Will my number change in the cloud PBX?
No. Your existing fixed number can be transferred to the cloud PBX through number portability; your customers can continue to reach you at the same number.
If my internet goes down, will my phones completely shut down?
In the cloud PBX, external calls are affected since they come over the internet; however, a backup rule is configured so that calls are automatically forwarded to GSM numbers, thus the caller does not reach a dead end. Internal calls on the on-premise IP PBX are not affected by the outage.
Can I continue using my old analog PBX?
Yes, if it is working and meets your needs; we maintain it, replace faulty cards and phones. If remote work, call recording, and reporting are required, migration to IP or cloud PBX is recommended.
How many internal extensions can it support?
In a cloud PBX, the number of internal extensions increases with the subscription; there is practically no limit. In the IP PBX, dozens to hundreds of extensions are supported depending on licenses and hardware. In an analog PBX, it is limited by card capacity.
How long does installation take?
A cloud PBX can be put into service the same day if the line is ready. In a IP PBX installed in the office, it typically takes 1–3 days depending on the cabling situation; if existing cabling is suitable, the time is reduced.