IP telephony uses several key Internet protocols that ensure that calls work correctly:
SIP (Session Initiation Protocol)
This is the main standard for VoIP calls . It is responsible for the establishment, management and termination of calls . SIP allows you to: – Route calls between users. – Connect different devices – SIP phones, softphones, IP PBX. –
Provide encryption norway email list 1.6 million contact leads and authentication of calls.
RTP (Real-Time Transport Protocol)
This protocol transmits the audio itself during a call. It works together with SIP, providing low latency and high-quality audio.
H.323
An old standard for VoIP us in large corporate systems and video calls
WebRTC
A protocol that allows you to make calls directly from your browser ,
without installing additional programs.
3. Codecs: how connection quality is ensur Basic IP telephony
Codecs are algorithms that compress chrome user experience report and transmit voice data while minimizing network load.
— G.711 – high quality, but requires more internet. — G.729 – saves traffic,
but compression ruces quality. — Opus – a modern codec, adapts to network spe.
Example: For corporate calls with good internet it is better to use G.711 , and for mobile and international calls – G.729 or Opus to avoid connection interruptions.
Equipment for IP telephony Basic IP telephony
Depending on the tasks, different devices can be us for IP telephony :
— SIP phones are classic VoIP devices that connect via the Internet. — Softphones are programs for PCs and smartphones (Zoiper, Linphone, Bria). — IP PBX are trust review virtual or hardware stations for routing calls. — VoIP gateways allow you to connect analog phones to an IP network.
Example: SIP phones can be install in the office for employees, and remote workers can be given softphones – they will be able to answer calls from a laptop or smartphone.
How are calls rout?
IP telephony uses intelligent routing to route calls to the right operator or point in the network .
Incoming calls can be distribut: – By department (sales, support, accounting). – By geography (clients from Ukraine are answer by an operator in Kiev, and from Europe – in Berlin). – By schule (out of business hours, calls go to an answering machine or are forward).