ELASTIC SIP TRUNKING

Elastic SIP trunking: scale on demand with no busy signals.

Connect any PBX, contact center or carrier to MCM with SIP trunks that scale with demand. Resell them under your logo, with MCM AI catching overflow.

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  • Channels that grow and shrink with traffic
  • 190+ countries at 99.99% uptime
Trunk trafficchannels: auto Live
Calls Provisioned channels
MorningMiddayEvening
Morning
Steady
Midday
Peak
Overflow to MCM AI
Standby
Uptime
99.99%
01Why teams build here

Why choose elastic SIP trunking

Capacity that follows demand, a trunk that works with any phone system, and an AI that catches every overflow call.

01

Scale without limits

Channels grow and shrink with real traffic automatically, so a big launch never hits a busy signal.

scale.rules
trunk: northwind-retail
channels: auto
scale_up: on traffic spike
scale_down: when it calms
billing: pay as you go
no busy signals
02

Connect any PBX

Point any SIP-compatible phone system at MCM and bring it online in minutes.

pbx.conf
sip_host: pbx.example.com
allowed_ips: 203.0.113.10
auth: credentials
numbers: your existing DIDs
setup: by API
trunk registered
03

AI on overflow

MCM AI catches busy and after-hours calls instantly, so no caller slips away.

overflow.rule
when: all lines busy
or: after hours
or: unanswered
route: MCM AI
summary: pushed back
no caller lost
02Elastic capacity

Scalable SIP trunking that follows your traffic

Trunks scale with each traffic spike and shrink when it calms down. Your customers pay for what they use and never hit a busy signal during a big launch or a holiday rush.

Traffic is steady, so only a few channels are provisioned.

Live load
17active calls
0 busy signals
Provisioned channels
24channels, growing and shrinking
Active calls Provisioned

Capacity stays ahead of demand, so callers never hear a busy signal.

Pay as you go
Idle capacity
Not provisioned, not billed

Illustrative demand. Your customers pay for what they use.

  • Auto scaling channels
  • Pay as you go
  • No busy signals
03Works with any system

SIP trunk for any PBX, contact center or carrier

Point any SIP-compatible PBX, contact center or carrier switch at MCM. Configure trunks, IPs and credentials by API, and reach 190+ countries with 99.99% uptime.

Your system
Any SIP PBX
On-site or hosted phone system
Set up by API
nameallowed_ipsauthchannels: auto
POST /2026-01/trunks
Connecting
  1. Allowed IPs checked
  2. 2Credentials verified
  3. 3Trunk registered
MCM SIP trunk
Waiting
Calling worldwide
Ready the moment it registers
190+ countries
USUKDEBRINAUZAJPMXSG+
99.99% uptime
  • Any SIP PBX
  • API trunk setup
  • Calling to 190+ countries
04MCM AI on the trunk

Overflow, after-hours and unanswered calls go to MCM AI

Send overflow, after-hours or unanswered calls to MCM AI right from the trunk. It answers, captures details and pushes a summary back, so no caller slips away.

When
MCM AI answers
Overflow · all lines busy
CALLERIs the blue jacket in stock?
tool_callcheck_stock() in stock
MCM AIYes, one left in your size. Shall I place the order?
Live on the trunk · no caller left waiting
Then
  • Details captured
    Name, reason and stock check
  • Summary pushed back
    Written after every call
  • Supervisor reviews
    Sees the AI summary and order
  • Overflow to AI
  • After hours answering
  • Call summaries
05Step by step

How an overflow call is handled, step by step

Follow one call to a busy retailer, from a full line to a reviewed order.

  1. Line full
    01 · Caller

    Calls a retailer during a busy sale when every line is full.

  2. Overflow rule fires
    02 · Network

    Detects the trunk is busy and triggers the overflow rule.

  3. Answered by MCM AI
    03 · MCM AI

    Answers the call, checks stock through a tool and helps the caller.

  4. Summary reviewed
    04 · Supervisor

    Reviews the AI summary and sees the order was placed.

06Who it is for

Who uses elastic SIP trunking

Built for carriers and partners who resell trunks, and for teams who run their own phone systems.

Aggregators

Connect straight to the trunks and manage them by API.

Resellers

Brand SIP trunks as your own and sell them under your logo and pricing.

Contact centers

Add capacity for peaks and send overflow to MCM AI.

Businesses with a PBX

Bring an existing phone system online with SIP in minutes.

Testimonials

What clients say after 90 days.

Real teams, real numbers — from sales floors, CX desks, and support queues.

“We tried three cloud phone tools before this one. The reason we stayed is boring — it just kept working across four time zones. Our sales team stopped thinking about the phone.”

Arjun Mehta

Head of Growth · Chennai

“The mid-shift dashboard is where I actually spend my day. Queue depth, agent load, and sentiment on one screen — I can coach someone before it turns into a bad review.”

Rachel Monroe

CX Manager · Denver

“AI covers overflow calls in Hindi and English, so we stopped losing weekend leads. It's not perfect — it hands off to us on anything ambiguous — but for hours and bookings, it beats voicemail every time.”

Priya Nair

Support Lead · Bengaluru

“HubSpot sync is quiet infrastructure. Every call, note, and recording just shows up on the contact — nobody has to remember to log it. That's why our forecast is finally accurate.”

Daniel Carter

Head of Sales · Chicago

“I set the whole thing up on my phone during a delayed flight. Six people, three countries, one number that rings all of us. My old provider needed a two-week onboarding for the same thing.”

Neha Iyer

Founder · Mumbai

“Porting 40 numbers across three countries was the part I dreaded most in the migration. It was done in a week, free, and I only had to sign one form. That set the tone for the rest of the rollout.”

Sophie Laurent

COO · Paris

+24%

First Contact Resolution

11 hrs

Per week returned to sales

−38%

Average Handle Time

FAQ

The questions teams ask on the first call.

Will SIP trunking work with my existing PBX?expand_more

Yes. Any SIP-compatible PBX, contact center or carrier switch connects to MCM in minutes.

How does elastic SIP trunk scaling work?expand_more

Channels grow with live traffic and shrink when it drops, so your customers only pay for what they use and never hit a busy signal.

Can aggregators connect directly to the SIP trunks?expand_more

Yes. Aggregators connect straight to the trunks and manage them by API.

Can I set up SIP trunks by API?expand_more

Yes. Configure trunks, IPs and credentials by API, and reach 190+ countries with 99.99% uptime.

Can MCM AI take overflow calls from the trunk?expand_more

Yes. Route busy, after-hours or unanswered calls to MCM AI. It answers right away, captures details and pushes a summary back.

Can I resell SIP trunks under my own brand?expand_more

Yes. Resellers brand the trunks as their own and sell them under their logo.

Ready to launch elastic SIP trunks?

Talk to our partner team and go live with scalable SIP trunking under your own brand.

Book a DemoTalk to Sales
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