Abbreviations A–Z

Every abbreviation and term used in the Silux Call dashboard and help guides, explained in plain English. 89 terms.

0

01 / 02 — Geographic numbers
UK landline numbers tied to a town or city by their area code, such as 0161 for Manchester or 020 for London.
Example: 0113 (Leeds) and 020 (London) are geographic numbers.
Used in: Phone Numbers, Buy a Number, Number Porting
03 / 08 — Non-geographic numbers
UK numbers not tied to a place. 03 costs callers the same as a landline call; 08 numbers can carry extra charges.
Example: 0800 and 03 numbers are non-geographic; they are not tied to a place.
Used in: Buy a Number, Number Porting

2

2FA — Two-Factor Authentication
Signing in with your password plus a one-time code sent to your phone, so a stolen password is not enough.
Example: After your password you type a 6-digit code from your phone: that is 2FA.
Used in: Users, Settings

9

999 / 112 — UK emergency numbers
Both reach the emergency services in the UK. Over VoIP the operator is given the address you register, not your live location.
Example: Dial 999 or 112 from your Silux Call line and it reaches the emergency services; register your address so they know where to come.
Used in: Number Porting, Emergency 999

A

ACD — Automatic Call Distribution
The logic that hands waiting callers in a queue to the next free person. Call Queues use it.
Example: In a call queue, ACD hands the next caller to the agent who has been free longest.
Used in: Call Queues, Live Calls
AMD — Answering Machine Detection
Spotting when an answerphone, not a person, picks up an outbound call.
Example: On an outbound call, AMD can tell that a voicemail greeting picked up rather than a person.
API — Application Programming Interface
A way for other software to talk to your account automatically.
Example: Your developer uses the API to pull call history into your own reports.
Used in: Settings
API key
A secret password that lets one piece of software use another. Treat it like a password.
Example: Treat an API key like a password: anyone with it can use your account's API.
Used in: CRM Integration
Auto-attendant — Automated attendant
Another name for an IVR / greeting menu — a recording that answers and directs callers without a receptionist.
Example: "Thank you for calling. Press 1 for sales, 2 for support" is an auto-attendant.
Used in: Greeting Menu

B

BACS — Bankers' Automated Clearing Services
The UK system behind Direct Debit payments from a bank account.
Example: Direct Debit payments are collected through BACS, usually in about three working days.
Used in: Billing
Barge — Barge-in
A supervisor joins a live call so both the caller and the colleague can hear them.
Example: A supervisor barges in to help with an angry caller, and both the agent and caller can hear them.
Used in: Call Monitoring
BLF — Busy Lamp Field
A live light (or icon) showing whether a colleague's extension is free, ringing or on a call — so you know before you transfer.
Example: A green light next to extension 202 means Tom is free; red means he is on a call.
Used in: Line Status (BLF)
BST — British Summer Time
UK clock time from late March to late October, one hour ahead of UTC.
Example: From late March to late October UK time is BST, one hour ahead of UTC.
Used in: Business Hours

C

Call park
Putting a call in a numbered "parking slot" so anyone can pick it up from any phone by dialling that slot.
Example: Park a call in slot 701 and pick it up from the warehouse phone by dialling 701.
Used in: Call Park
CDR — Call Detail Record
One line in your call history: who called whom, when, for how long, whether it was answered, and what it cost.
Example: Each line in Call History (time, from, to, duration, status) is one CDR.
Used in: Overview, Call Recording, Analytics & CDR
CLI — Calling Line Identity
Caller ID — the number shown to the person you call, and the number you see when someone calls you.
Example: When you call a customer they see your business number, 01632 960123, as the CLI.
Used in: Scam Shield
CNAME — Canonical Name record
A DNS setting that points your own web address (such as phones.yourcompany.co.uk) at our platform.
Example: Point phones.yourbrand.co.uk at the portal with a CNAME record at your domain provider.
Used in: Portal Branding
Codec — Coder-decoder
The method used to squeeze voice into data and back again. You do not need to set it — the system chooses the best one.
Example: G.711 and Opus are codecs; your phone and our servers agree which one to use on each call.
Concurrent calls — Concurrent calls / lines / channels
How many calls your account can have going at the same moment. On Silux Call it is one per user you pay for.
Example: Three people on the phone at the same time = three concurrent calls.
Used in: Call Waiting, Settings
CP — Communications Provider
Any phone or broadband company. "Losing CP" is the provider you are leaving; "gaining CP" is us.
Example: Your old phone company is the losing CP; Silux Call is the gaining CP.
Used in: Number Porting
CRM — Customer Relationship Management
Software that holds your customer records, such as HubSpot, Salesforce, Zoho or Pipedrive.
Example: HubSpot, Salesforce and Zoho are CRMs.
Used in: CRM Integration
CSS — Cascading Style Sheets
Code that controls colours and layout on a web page. Only needed for advanced branding.
Example: CSS controls the colours and fonts on your branded portal.
Used in: Portal Branding
CSV — Comma-Separated Values
A simple spreadsheet file that opens in Excel, Google Sheets or Numbers.
Example: Export your call history as CSV and open it in Excel or Google Sheets.
Used in: Analytics & CDR, Activity Log

D

DD — Direct Debit
Paying automatically from your bank account each month.
Example: Pay by Direct Debit and your monthly bill is collected from your bank account automatically.
Used in: Billing
DDI — Direct Dial In
The UK name for a DID — a number that reaches someone directly without going through a switchboard.
Example: Give your accounts team their own DDI so customers can call them without going through the main menu.
Used in: Phone Numbers, Company Directory
Dialplan
The phone system's instructions for what happens to each call. Your dashboard writes it for you — you never edit it by hand.
Example: The dialplan decides that a call to your number plays the greeting menu first.
Used in: Call Routing, Business Hours
DID — Direct Inward Dialling
A phone number that rings straight through to a person, team or menu on your system. Each number on your Phone Numbers page is a DID.
Example: Your 0161 number is a DID; it can ring Jane directly without going through reception.
Used in: Phone Numbers, Buy a Number, Call Routing
DND — Do Not Disturb
Stops your phone ringing. Callers go to voicemail instead. Outgoing calls still work.
Example: Turn DND on during a meeting and calls go to voicemail until you turn it off.
Used in: Do Not Disturb, Softphone
DNO — Do Not Originate
A list of numbers that organisations such as banks and HMRC only ever receive calls on and never call out from. A call that shows one as its caller ID is fake by definition.
Example: Some HMRC and bank numbers are only ever used to receive calls, so a call from one is blocked by Scam Shield.
Used in: Scam Shield
DNS — Domain Name System
The internet's address book, managed wherever you bought your domain name.
Example: DNS is the internet's address book that turns a web address into a server.
Used in: Portal Branding
DTMF — Dual-Tone Multi-Frequency
The tones your phone makes when you press keypad buttons. Menus and card payments read these tones.
Example: Pressing 1 in a phone menu sends a DTMF tone that tells the system which option you picked.
Used in: Greeting Menu, Softphone, Recording Settings, Payments
Duplex — Full duplex
Two-way audio — both sides can speak at the same time. In paging, duplex turns a one-way announcement into an intercom.
Example: In duplex paging the person you page can talk straight back, like an intercom.
Used in: Paging / Intercom

E

E.164 — International number format
A phone number written with + and the country code and no leading zero, such as +44 161 496 0000. Some fields accept this format.
Example: 01632 960123 written in E.164 format is +441632960123.
Used in: Phone Numbers, Business SMS
Ext. — Extension
A short internal number (usually 3 or 4 digits) for each person or phone. Calls between extensions are free and never leave your system.
Example: Dial 204 to reach the warehouse.
Used in: Greeting Menu, Hunt Groups, Company Directory, Voicemail Settings

F

Find me / follow me
One incoming call tries several of your phones in turn — desk, then mobile, then home — until you answer.
Example: Ring the desk for 15 seconds, then the mobile, then voicemail.
Used in: Find Me / Follow Me

H

HD voice — High-definition (wideband) voice
Clearer, fuller call audio than a traditional phone line when both ends support it.
Example: Two softphone users talking on HD Voice sound noticeably clearer than an old landline.
Used in: Softphone
Hunt group — Hunt group / ring group
Several phones that ring for one call — all at once, one after another, or taking turns — so someone always answers.
Example: A "Sales" hunt group rings Jane, Tom and Priya until one of them answers.
Used in: Call Routing, Hunt Groups

I

ISDN — Integrated Services Digital Network
Older digital business phone lines, also being switched off with the PSTN.
Example: Many offices still have ISDN lines that stop working when the PSTN is switched off; porting the numbers to VoIP keeps them.
IVR — Interactive Voice Response
The recorded menu that answers a call and asks the caller to press a key — "press 1 for sales, press 2 for accounts". Each key sends the call somewhere: a person, a team, voicemail or another menu. It lets a small business sound like a large one and gets callers to the right person first time. In your dashboard it is called a Greeting Menu.
Example: "Thank you for calling Smile Dental. Press 1 to book, press 2 if you are in pain today, press 3 for billing." Press 2 and the call rings the emergency nurse, not reception.
Used in: Call Routing, Greeting Menu, Greetings, Payments

J

Jitter — Jitter (ms)
How unevenly the pieces of your call arrive. Under 30 ms is good; high jitter sounds choppy or robotic.
Example: Jitter of 3 ms is fine; 40 ms makes speech choppy.
Used in: Network Quality

L

Latency — Latency (ms)
How long your voice takes to reach the other end, in milliseconds. Under 150 ms feels natural.
Example: 30 ms latency is fine; over 150 ms you start talking over each other.
Used in: Network Quality
Listen-in — Silent monitoring
A supervisor hears a live call without either person hearing them.
Example: A manager listens in on a new starter's call without either person hearing them.
Used in: Call Monitoring
LOA — Letter of Authority
A signed letter from the account holder agreeing to move their numbers to us. Your current provider will not release numbers without it.
Example: You sign the LOA online when you ask to bring your number over from BT.
Used in: Number Porting

M

MOH — Music On Hold
What callers hear while they wait on hold or in a queue — music, a message, or both.
Example: The music a caller hears while you check stock is MOH.
Used in: Call Queues, Hold Music, Call Hold
MOH class — Music-on-hold class
The named set of hold music the phone system plays. You set it by choosing a default track on the Hold Music page.
Example: Choose a default track on Hold Music and that becomes the MOH class callers hear on hold.
Used in: Hold Music
MOS — Mean Opinion Score
A call-quality score from 1 (unusable) to 5 (perfect). 4.0 or more is excellent; under 3.5 people will notice problems.
Example: A MOS of 4.2 is good call quality; below 3.5 people start to notice.
Used in: Network Quality
MP3 / WAV — Audio file formats
The two most common sound file types. WAV is full quality and larger; MP3 is smaller.
Example: Download a recording as MP3 to email it; keep the WAV if you need the original quality.
Used in: Greeting Menu, Voicemail, Voicemail to Email, Greetings
MRR — Monthly Recurring Revenue
What all of a reseller's customers pay each month, added together.
Example: 20 customers paying £10 a month = £200 MRR.
Used in: Reseller Portal
ms — Milliseconds
Thousandths of a second.
Example: 150 ms is 0.15 of a second.
Used in: Network Quality

N

NAT — Network Address Translation
What your router does to share one internet address between all your devices. It is the usual cause of one-way audio.
Example: Your router uses NAT so every device in the office shares one internet address.
Used in: Network Quality

O

Ofcom — Office of Communications
The UK telecoms regulator. Its rules cover 999 access, number porting and caller ID.
Example: Ofcom sets the UK rules on number porting and emergency calls.
Used in: Number Porting, Emergency 999
OTP — One-Time Passcode
A short code that works once, sent by text for signing in or confirming something.
Example: The 6-digit code texted to you when you sign in is an OTP; it works once and expires.
Used in: Business SMS, Settings, Ordering SMS & WhatsApp
Overage — Overage / out-of-bundle
Usage beyond what your plan includes, such as minutes past your allowance, charged at your standard rate.
Example: If your plan includes 500 minutes and you use 520, the extra 20 are overage.
Used in: Subscription & usage, Calling Bundles
Overflow — Overflow routing
Where a call goes when a queue is full or has waited too long — voicemail, another number, or hang up.
Example: If nobody in Sales answers within 2 minutes, the call overflows to the Office group.
Used in: Call Queues

P

Packet loss — Packet loss (%)
The share of call audio that never arrives. Under 1% is good; above 3% causes gaps.
Example: 1% packet loss is barely noticeable; 5% makes words drop out.
Used in: Network Quality
Paging — Paging / intercom
A one-way announcement that comes out of many handsets at once, like a tannoy. Duplex (intercom) mode lets people reply.
Example: Dial the paging group and say "Delivery at the back door" to every phone in the group.
Used in: Paging / Intercom
PBX — Private Branch Exchange
A business phone system — the "switchboard" that decides which phone rings, holds callers, transfers them and plays menus. Ours is hosted (in the cloud), so there is no box in your office.
Example: Your Silux Call account is a hosted PBX: extensions, menus and transfers all run on our servers, so there is no box in your office.
PCI DSS — Payment Card Industry Data Security Standard
The card schemes' security rules for anyone who takes card payments. Taking card numbers by keypad (so staff never hear them) and pausing recordings during payment keeps card data out of your business.
Example: Taking card numbers by keypad, with recording paused, keeps card data out of your recordings, as PCI DSS requires.
Used in: Recording Settings, Payments
PDF — Portable Document Format
A document file for invoices and statements.
Example: Invoices download as PDF files you can print or send to your accountant.
Used in: Billing
PIN — Personal Identification Number
A short number code — used for voicemail access and conference rooms.
Example: Your voicemail PIN, e.g. 4826, stops anyone else listening to your messages.
Used in: Voicemail Settings, Conference Bridges
Porting — Number porting
Moving an existing phone number from one provider to another so you keep the same number.
Example: Moving your 0113 number from your old provider to Silux Call, keeping the same number.
Used in: Number Porting
PSTN — Public Switched Telephone Network
The old copper phone network. BT Openreach is switching it off by January 2027, after which landlines run over the internet — which is what Silux Call already does.
Example: The old copper phone network that BT is switching off by 31 January 2027.

R

Range holder
The network operator that owns the block your number comes from — often not the company that bills you. You never need to know it; we can look it up.
Example: Your bill may come from one company while the number block belongs to another network; that network is the range holder.
Used in: Number Porting
Ring strategy
The rule for which phone rings next: Ring All (everyone at once), Sequential (in order), Round Robin (take turns), Least Recent (whoever has waited longest since their last call) or Fewest Calls.
Example: Ring all, one by one, or taking turns: each is a ring strategy.
Used in: Hunt Groups, Call Queues
RIPA — Regulation of Investigatory Powers Act
UK law covering interception of communications — the reason staff must be told that calls may be monitored or recorded.
Example: Put a line in staff contracts and your greeting saying calls may be monitored or recorded.
Used in: Call Monitoring

S

Screen pop
The caller's customer record opening on your screen automatically as the phone rings.
Example: The caller's customer record opens on your screen as the phone rings.
Used in: CRM Integration
SIP — Session Initiation Protocol
The standard language internet phones use to make and receive calls. Desk phones and apps "register" to your account with SIP.
Example: A desk phone or app signs in to your account using SIP, with a username, password and server address.
Used in: Softphone, Extensions
SIP 603 — SIP response 603 "Decline"
The signal Scam Shield sends back when it blocks a call: the call is refused before your phone rings.
Example: Scam Shield blocks a spoofed call with SIP 603, so the scammer hears the call refused and your phone never rings.
Used in: Scam Shield
SLA — Service Level Agreement
The service availability we commit to for your plan, published on our legal pages.
Example: An SLA sets out the uptime and response times a service commits to.
SMS — Short Message Service
An ordinary text message.
Example: A missed-call alert that arrives on your mobile as a text is an SMS.
Used in: Buy a Number, Missed Calls, Call Alerts (SMS & WhatsApp), Business SMS
Softphone — Software phone
A phone that is an app or a browser tab rather than a handset on a desk.
Example: Taking calls on your laptop with a headset uses a softphone instead of a desk phone.
Used in: Softphone, Extensions
Spoofing — Caller ID spoofing
When a scammer fakes the number shown on your screen — for example making a call look as if it comes from HMRC. Scam Shield catches the most common forms.
Example: A call that shows your bank's number but asks for your PIN is almost certainly spoofed.
Used in: Scam Shield
STUN — Session Traversal Utilities for NAT
A helper server that tells your phone its public internet address so calls can connect through your router.
Example: STUN lets your softphone find its public internet address so calls connect through your router.
Used in: Network Quality

T

Tenant — Tenant / organisation
Your company's account on the platform. The Tenant ID is its reference number — support may ask for it.
Example: Your business is one tenant on the platform; nobody else can see your calls or settings.
Used in: Overview, Users, Settings, My Customers
Transcription — Speech to text
Turning recorded speech into written text you can read and search.
Example: A voicemail transcription lets you read "Hi, it's Sarah about the quote" instead of listening.
Used in: Voicemail, Voicemail Settings, Voicemail to Email, Call Recording
TTS — Text to speech
Typing words and having them spoken in a natural voice. The Greetings studio and Greeting Menus use it.
Example: Type "We are closed for lunch" and TTS turns it into speech in the voice you choose.
Used in: Greeting Menu, Greetings, Call Whisper, Smart Voice
TURN — Traversal Using Relays around NAT
A relay server that carries call audio when a strict router or firewall would otherwise block it.
Example: If your office firewall blocks direct audio, a TURN server relays it so the call still works.
Used in: Network Quality

U

UK GDPR — UK General Data Protection Regulation
The UK's data protection law. For recordings it means: tell people, have a reason, and keep them no longer than you need.
Example: Keeping recordings only as long as you need them (for example 90 days) is part of meeting UK GDPR.
Used in: Call Monitoring, Call Recording, Recording Settings, Transcription
URL — Uniform Resource Locator
A web address, such as https://example.com/hook.
Example: https://www.siluxcall.co.uk/help is a URL.
Used in: Smart Configuration, CRM Integration, Settings
UTC — Coordinated Universal Time
World standard time. The UK is on UTC in winter and UTC+1 (BST) in summer — choose Europe/London and the change happens for you.
Example: In July, 14:00 UTC is 15:00 UK time; pick Europe/London as your time zone and you never need to work it out.
Used in: Business Hours

V

VAT — Value Added Tax
UK sales tax, charged at 20% on top of prices shown excluding VAT.
Example: Prices are shown excluding VAT; 20% VAT is added on your invoice.
Used in: Features & Add-ons, Billing, Customer Billing, Portal Billing
VoIP — Voice over Internet Protocol
Phone calls carried over an internet connection instead of a copper phone line. Every Silux Call line is VoIP, which is why it works anywhere you have internet.
Example: Your 0161 number rings on your laptop in a hotel in Spain.
Used in: Emergency 999

W

Webhook
An automatic message our system sends to a web address you choose whenever something happens, such as a call ending. Used to connect other software.
Example: When a call ends, a webhook sends its details to your own system automatically.
Used in: Smart Configuration, CRM Integration, Settings
WebRTC — Web Real-Time Communication
The technology that lets your web browser make and take phone calls without installing anything. The Softphone page uses it.
Example: The dashboard softphone uses WebRTC, which is why it works in Chrome with nothing to install.
Used in: Softphone
what3words — what3words address
Three words that pinpoint a 3-metre square anywhere in the world — useful for large sites and rural premises.
Example: A what3words address such as ///filled.count.soap pinpoints a 3 metre square, useful for rural premises.
Used in: Emergency 999
WhatsApp
The messaging app. Call alerts and the WhatsApp Business inbox send and receive messages through it.
Example: A missed-call alert can arrive as a WhatsApp message instead of a text.
Used in: Missed Calls, Call Alerts (SMS & WhatsApp), WhatsApp Bot, Ordering SMS & WhatsApp
Whisper — Whisper / whisper coaching
Speaking to your colleague during a live call without the caller hearing. Call Whisper (the menu item) is different: a short message played to whoever answers before the caller is connected.
Example: A supervisor whispers "offer the discount" and only the agent hears it.
Used in: Call Whisper, Call Monitoring
White label
Our platform sold by a partner under the partner's own name, logo and colours.
Example: A reseller sells our phone system under their own brand: that is white-label.
Used in: Reseller Portal, My Customers, Portal Branding, Customer Billing
Wrap-up — Wrap-up time
A pause after a queue call ends before that person is given another, so they can finish notes.
Example: A 30-second wrap-up time lets an agent finish their notes before the queue sends the next call.
Used in: Call Queues

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