IP Telephony Server by Asterisk

IP Telephony Server

What is This and Which one is Best?

The Asterisk IP telephony server is today the core of telephone communications and the quality of its work depends on the work of your company’s telephony. Since IP telephony replaces the usual classic analog-digital office telephone stations each coming day, the telephone stations become fully software. There are of course also hybrid IP-PBX, but at its core, it is also a software system.

The main players, for today, in the manufacturing of IP-PBX and call centers are two absolutely free programs – Asterisk and FreeSWITCH. Each system has its advantages and disadvantages when used in a particular infrastructure.

Which points should be considered while choosing the server for the IP-telephony platform?

First of all, it is necessary to determine the number of employees (subscribers), that need connection. After this count the one-time number of calls and the number of external lines (channels).

Server case

Basically, there are two types of shell Tower (outdoor) and Rack-mount (rack).

Asterisk IP Telephony Server

Tower building is perfect for small companies when there is no server room, rack, and telecommunication cabinet. Such cases are initially cheaper when choosing it is worth paying attention to proper ventilation and matching connectors for your components.

IP Telephony Server

Rack-mount rack enclosures are suitable for a company with a developed telecommunications infrastructure. The height (units) and depth of the server are selected based on the installation location and capabilities. When placing a server in a data center or a data center, it’s worth looking at 1U servers.

Operative memory (RAM)

Server memory

In most cases, the amount of memory in 2 GB is enough, but most often for customers, we recommend to put 4GB, leaving a reserve for the future and increasing the load.

Server Processor

For the IP telephony server, the main processors are Intel Core and Intel Xeon, the first are more budgetary and affordable, the latter is more expensive and productive.

On average, one connection consumes 30 MHz of the processor frequency. Therefore, knowing the processor clock speed, you can calculate how many simultaneous connections it can perform. For example, Intel Core i3 with a clock speed of 3 GHz, we get about 100 simultaneous connections (conversations).

Hard Drive (HDD)

Server hard disk

The main criterion for choosing a hard disk for ATC is its capacity, how many records, in a word, it can store in itself. By default, conversations recorded without compression in WAV format. As a result, 1 minute of talk takes as a rule 1 MB of HDD space. In the system itself, configured replication and for example PBX robot deletes the records older than a year or two. For medium-sized companies, a hard drive of 500GB-1TB is enough.

For reliability, some companies use a RAID controller, (in the case of RAID1) use two hard drives (mirroring) and in the event of a failure of one of the disks, all the necessary information remains on the other. But there is one BUT, in modern budget motherboards, the implementation of a software RAID is software, and the controller itself is out of order more often than a hard disk).

Power Supply

Server Power Supply

The power unit is worth choosing famous and proven brands, the power of 550-600 watts is optimal. The simplest (private) verification of the quality of the power supply is its weight. The more weight the more the filter inductances and capacities the unit possess. In heavily loaded servers, they use two power supplies with separate power. This guarantees the higher level of reliability.

Separately, we’d like to mention about virtual machines. As the practice shows and the developers conclude themselves, virtual machines behave not so reliably and predictably as full-fledged hardware servers.