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Glossary

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  • Glossary
B
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F
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B

Blacklist

Find out what a call blacklist is, how it helps block unwanted calls, and why both businesses and individuals rely on it. We’ll walk through real use cases and answer common questions.

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C

Call Forwarding

Call forwarding is a simple but powerful feature that sends incoming calls from one number to another — automatically. Whether you’re traveling, working from home, or just stepping away from your desk, your callers still reach you.

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Call Recordings

A call recording is exactly what it sounds like — saving a copy of a phone conversation so it can be listened to later.

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Callback

A callback is when a company calls a customer back instead of keeping them on hold. Imagine you’re trying to reach customer support, but the line is busy or you don’t feel like waiting with the phone glued to your ear. You just leave your number, and the company gets back to you once someone is free.

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CPaaS

CPaaS (Communications Platform as a Service) is basically a cloud-based toolbox for communication. Instead of investing in complicated telecom infrastructure, a business can simply “plug in” features like phone calls, SMS, video chats, or even two-factor authentication into its own app or website through easy-to-use APIs.

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D

DID number

When someone wants to call your company, they don’t want to get lost in endless menus or wait forever. They just want to talk to the right person. That’s where a DID number comes in. It’s a simple way to make your communication smoother, faster, and more professional.

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F

Fixed VoIP

These days, most business calls happen online. That’s VoIP in action—using the internet instead of old-school phone lines. But not all VoIP services are the same. Fixed VoIP is a type that’s often overlooked but highly valued by companies that care about reliability, trust, and a professional image.

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H

Hosted PBX

Remember when office phones meant heavy equipment and expensive tech setups? Those days are fading fast. Hosted PBX is basically your phone system, but without the hassle. Instead of keeping hardware in your office, everything runs through the internet, managed by your provider.

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I

IVR

If you’ve ever called a company and heard a friendly voice say, “Press 1 for sales, 2 for support,” you’ve experienced IVR. It stands for Interactive Voice Response, and it’s an automated system that helps callers reach the right person or get the right information quickly. Instead of waiting on hold or being transferred multiple times, customers can navigate through a simple phone menu and get answers faster.

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L

Landline

Before Wi-Fi and smartphones, almost every home and office relied on a landline. This is the traditional phone service that connects calls through wires—usually copper or fiber cables. Even though mobile phones and internet calling (VoIP) are now common, landlines are still around because they are stable, simple, and often work even when other systems fail.

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N

Non-fixed VoIP

Today, most of us live and work online. Businesses are expanding globally, and people are no longer tied to one office or one country. That’s why non-fixed VoIP has become such a popular solution.

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P

PRI

With so many businesses moving to cloud phones and VoIP, you might think older technologies are long gone. But that’s not true—Primary Rate Interface (PRI) is still around, and for good reason. It’s a solid, dependable way for companies to handle a lot of calls at once, with great sound quality and minimal downtime.

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R

RTP (Real time Transport Protocol)

When you make a voice call on WhatsApp, join a Zoom meeting, or use VoIP in your office, RTP is quietly doing the heavy lifting. It’s the technology that makes sure your voice, video, or any real-time data reaches the other side quickly and smoothly. Without RTP, internet calls would be slow, choppy, or completely unusable.

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S

SIP ALG

If you use VoIP for business or personal calls, you might have heard about SIP ALG. It is a feature in many routers that is supposed to “help” with internet phone calls. The problem is that in most cases, it does the opposite, causing dropped calls, poor quality, or connection errors. That is why understanding SIP ALG is important for anyone who wants stable online communication.

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SIP Proxy server

When you make a call over the internet, it feels simple: you dial, someone picks up, and you start talking. But behind the scenes, there’s a system making sure your call finds the right path. One of the key parts of that system is the SIP proxy server. Without it, many VoIP calls would never connect properly.

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SIP trunk

SIP trunking makes business phone calls easier, cheaper, and more flexible. Instead of using old-fashioned phone lines, it uses the internet to connect your company’s phone system. For businesses that make lots of calls or have teams in different countries, SIP trunks are a game-changer.

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SIP port

Every time you make a call over the internet, it feels instant — you press the number, hear the ring, and start talking. Simple for you, but behind the curtain, your call has to find the right path to connect. One of the key pieces that makes this possible is the SIP port. You can think of it as the “doorway” your VoIP calls walk through. If the wrong door is closed, your call might not even get started.

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T

TCP (Transmission Control Protocol)

Every time you open a website, send a message, or make a call online, something works in the background to keep everything running smoothly. That something is TCP. You don’t see it, you don’t control it, but without it the internet would feel messy and unreliable. Let’s take a closer look at what TCP is and why it’s so important for everyday online life.

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Toll Free number

Sometimes people hesitate to call a company because they don’t want to spend money on the call. A toll-free number removes that barrier. It gives your customers an easy, free way to reach you — and at the same time shows that you’re open, approachable, and ready to listen.

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U

UDP (User Datagram Protocol)

When you play an online game or join a live video call, you expect speed above everything else. That’s where UDP comes in. Unlike its careful sibling TCP, UDP doesn’t double-check every little detail. Instead, it just sends data as quickly as possible. The result? Faster performance — but with a small trade-off.

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V

Virtual PBX

Running a business means always staying connected — with clients, partners, and your own team. But let’s face it: traditional phone systems are heavy, outdated, and expensive to maintain. A Virtual PBX changes the game. Think of it as your business phone system, only smarter — living in the cloud. No tangled wires, no pricey equipment, just a flexible setup that works wherever you and your team do.

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Voicemail

We’ve all been there — the phone rings, but you’re in the middle of something important. Instead of losing that call forever, voicemail gives your caller a chance to leave a message. For businesses, it means customers always have a way to reach you. For personal use, it’s simply peace of mind that nothing slips through the cracks.

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VoIP number

A VoIP number looks just like a regular phone number, but it works through the internet. It gives you freedom: call from anywhere, stay connected on any device, and often pay much less than with traditional phone services.

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W

Whitelist

A whitelist is like a personal “VIP list” for your phone system. Only the numbers you trust get through. Unlike a blacklist, which blocks unwanted calls, a whitelist focuses on the opposite — it makes sure important contacts can always reach you.

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