Telephony (CTI) with the Fritzbox

Kontext connects the company phone with mail, contacts and calendar (CTI, computer telephony integration): when a customer calls, Kontext shows at once who it is – contact, company, latest mail, next appointment – and you answer in the browser, on the computer or on the phone. Calling someone is one click on the contact. The Fritzbox stays on the line, numbers and desk phones stay as they are; a small phone box in the office registers with the Fritzbox as an IP phone and connects it to Kontext. No phone system from the cloud, no cost per extension.

In testing

Telephony is being tested at the first customer. Feedback is welcome as an issue.

What you do with it

• A call with context: for the people who are meant to be rung, a card appears with the name, company, latest mail, next appointment and “Answer” – also as a notification on the device when Kontext is closed. If a number isn't in the address book, you see the number.
• Answer in the browser or on the desk phone: whoever picks up first has the call. Kontext is a softphone with microphone and speaker (WebRTC); the call stays open while you switch between mail, calendar and chat.
• Call from any contact, from the sidebar next to a mail or on the Phone page; a keypad sends tones for voice menus (DTMF).
• Call list with answered, missed and rejected calls, a note on the call and “Call back”.
• Call back as a task: a missed call creates “Call back: …” on the chosen board, due today; as soon as someone has spoken to the number, the task checks itself off.

Voicemail, opening hours, voice menu

• Voicemail: if nobody picks up, the box plays the greeting and records a message (up to two minutes). It arrives as a mail with the recording in the chosen mailbox and can be played on the call. You record greetings right in the browser or upload them.
• Opening hours with a lunch break, closed days and the public holidays of your own federal state with one click: outside them nothing rings, callers hear the “closed” greeting and can leave a message. The box checks this itself, even when Kontext can't be reached.
• Voice menu: “For customer service, press 1 …” – each key rings its own people (the topic is shown on the call) or leads to voicemail.
• Block list: “Block” in the call list, all withheld numbers if you want; the box rejects them before anything rings.

During a call

• Transfer to a colleague (it rings for her, you leave as soon as she's on), to any number or to a phone on the Fritzbox (**610).
• Hold, consultation, three-way call: hold music for the caller, ask a colleague first, then bring the caller back and talk as three – or leave the two of them alone.
• Record calls, if the company allows it: the box first plays the caller a notice (consent under § 201 StGB); the recording is kept with the call, it isn't mailed.

Who is rung when

• Everyone at once or one after the other (each person for a while, then everyone), plus, if you want, a mobile phone that joins in after a set time.
• Direct numbers: further numbers on the line, each rings its own people, who also call out with it.
• Presence: “on a call” is shown next to the person in the chat; with Do not disturb or Away until … it rings for the others (your own desk phone stays quiet too).

Devices in the office

• Snom desk phones register with the box and fetch their settings themselves (provisioning): they ring together with Kontext, reach each other by speed dial and can be chosen when transferring.
• Door intercom on the Fritzbox: it rings in Kontext with “Open door” and “Talk”.
• Fax as a PDF mail: one number on the line takes faxes; each arrives as a PDF in the chosen mailbox.
• Emergency calls (110, 112) and speed dials go straight through the Fritzbox; if the internet goes down, the phones on the Fritzbox keep working.

Statistics

Calls of the last 30 days: how many, how quickly they were answered, when calls were missed (weekday × hour), outside opening hours, messages and who answered.

What it needs

• a Fritzbox on the line (Telefonie → Telefoniegeräte → IP-Telefon “Kontext”, in English Telephony → Telephony Devices → IP telephone);
• the phone box in the office network: a container with Asterisk and the box agent, on a used thin client, a Raspberry Pi, the company server or a NAS with Docker. It sets up the connection to Kontext from the inside, no port is open at the customer's;
• LiveKit and LiveKit SIP on the server (in compose.yaml with the calls profile).

Setup step by step: Installation → Telephony. How the box, Asterisk, LiveKit SIP and Kontext work together: Architecture → Telephony. What comes next (a SIP trunk directly with the provider, SIP over TLS, a call queue, more desk phones): Roadmap.