SIP Trunking & Number Porting
Keep your PBX, swap the carrier. SIP trunks with managed number porting that preserves published numbers across the move — zero downtime, zero missed calls. Includes QoS marking, codec negotiation (G.711, G.729, Opus), configurable call admission control and SBC hand-off. Better economics on the pipe without replacing the system you already own.
Overview
Your PBX is not the problem; the carrier delivering the calls is. SIP Trunking replaces legacy PRI and ISDN circuits with session-based voice transport that scales from a single channel to thousands, with no hardware change at your premises. We deliver both India-based SIP trunks (through domestic carriers for local number presence and lowest per-minute rates) and Global SIP trunks (through international carrier interconnects covering 90+ countries) — so a single trunk group can carry local Mumbai calls and London calls with equal quality.
Clevertek scopes every engagement to your environment — capacity, sites, compliance and support model — so you get a tailored plan rather than a fixed SKU. Pricing is quote-only, and our solutions architects will work through your requirements before any proposal.
Our approach
We provision and manage SIP trunks that connect your PBX or cloud voice platform to the public telephone network — both domestic (India) and international (global) termination. Our India SIP trunks route through direct interconnects with Indian telcos for local number presence, CLIP compliance, and lowest domestic call rates. Our Global SIP trunks interconnect with carrier partners across 90+ countries, providing local termination in each market without requiring local numbers or local carrier relationships in every country. We handle SBC configuration, codec negotiation (G.711, G.729, Opus), QoS marking, call admission control, and number porting.
Why work with us
India SIP trunks with local presence
SIP trunks connected directly to Indian carrier exchanges — local, STD, and mobile calls terminate with optimal routing, CLIP compliance, and domestic per-minute rates.
Global SIP trunks — 90+ countries
International SIP termination to fixed and mobile networks across 90+ countries — UK, US, Canada, UAE, Singapore, Australia, Germany, France, Japan, and more — through direct carrier interconnects.
One trunk group, domestic and global
Domestic and international calls share the same trunk group — no separate circuits, no separate carriers, one set of QoS policies, one bill.
Number porting for Indian and international DDI
Port existing Indian DDI numbers to our SIP platform. International DDI numbers available from 90+ countries for local presence in target markets.
SBC management and codec negotiation
Session Border Controller configured and managed — codec negotiation (G.711, G.729, Opus, SILK), DTMF relay (RFC 2833/SIP INFO), and T.38 fax support included.
Scalable from 1 to 10,000 channels
No minimum channel commitment. Start with a handful of channels for a small office and scale to thousands for a contact centre — capacity added in minutes.
Key benefits
What this solution delivers for your business.
Replace PRI without replacing your PBX
Your existing PBX connects to SIP trunks the same way it connects to PRI — no hardware upgrade, no user retraining. The difference is in the cost and flexibility.
Local presence in 90+ markets globally
Global SIP termination means your business can establish voice presence in any major market without negotiating carrier agreements in each country.
Lower call costs than PRI or ISDN
SIP per-minute rates are typically 30-50% lower than PRI/ISDN equivalent. International termination through global SIP interconnects is significantly cheaper than ISD calls.
Capacity on demand
PRI gives you 30 channels per E1 — add or remove capacity in 30-channel blocks. SIP gives you per-channel granularity — add 5 channels for a campaign, release them when it ends.
Geographic number flexibility
Get DDI numbers from Indian cities (020, 022, 080, 044, 033, 011) and international cities (London 020, New York 212, Dubai 04, Singapore 65) on the same trunk.
Business continuity built in
SIP trunks can be rerouted to an alternate site or cloud PBX within minutes. No physical circuit to repair — a site outage does not mean lost calls.
What's included
Part of this managed service.
India SIP termination
Direct interconnects with Indian telcos for local, STD, and mobile termination — CLIP compliant, number porting supported.
- Direct Indian carrier interconnects
- Local, STD, mobile termination
- CLI presentation (CLIP)
- Domestic DDI porting
Global SIP termination
International termination to 90+ countries through direct carrier interconnects — local termination rates, no transit markup.
- 90+ countries covered
- Local termination per country
- UK, US, UAE, SG, AU, EU, APAC
- International number provisioning
SBC and codec management
Session Border Controller configuration and management — codec negotiation, DTMF relay, fax support, QoS marking.
- SBC management included
- G.711, G.729, Opus, SILK
- RFC 2833 DTMF relay
- T.38 fax support
Call admission control
Configurable CAC policies — max concurrent channels, emergency call capacity reservation, per-tenant limits.
- Per-trunk channel limits
- Emergency call capacity
- Per-customer limits (multi-tenant)
- QoS marking (DSCP EF/AF)
Number porting and provisioning
Port existing Indian DDI numbers. Provision international DDI numbers from 90+ countries.
- Indian DDI porting
- International DDI provisioning
- Number ranges per country
- Porting coordination handled
Where it helps
Real-world scenarios where this solution delivers measurable outcomes.
Multi-national contact centre
A contact centre serving customers in India, UK, and UAE — local and international calls on one SIP trunk group, Indian agents handle local calls, international agents handle global calls through the same platform.
Export business with global voice needs
An Indian export business with customers in 15 countries — one SIP trunk group carries calls to all markets, local DDI numbers in each country answer directly at the Pune HQ.
PRI to SIP migration
Migrate 10 offices from PRI to SIP — no PBX replacement, number porting coordinated per location, domestic and international calls on the same platform.
Questions buyers actually ask
What is the difference between India SIP and Global SIP?
India SIP trunks terminate calls within India through direct interconnects with Indian carriers — best for domestic calling with local number presence. Global SIP trunks terminate calls internationally through carrier partners in 90+ countries. Both can be combined on the same trunk group.
Do I need a Session Border Controller?
Yes for enterprise deployments — SBC provides security (topology hiding, DoS protection), interoperability (codec negotiation, protocol interworking), and QoS marking. We supply and manage the SBC as part of the service.
Can I keep my existing PBX?
Yes. SIP trunks are PBX-agnostic — Avaya, Cisco, Mitel, Panasonic, 3CX, Asterisk, Teams Direct Routing, and most cloud PBX platforms support SIP trunk registration.
How quickly can international numbers be provisioned?
Indian DDI numbers porting: 2-3 weeks. International DDI numbers in Tier 1 countries (UK, US, UAE, Singapore): 3-5 business days. Other countries: 1-2 weeks depending on local regulatory requirements.
Do you support emergency call routing?
Yes. Emergency calls are routed to the relevant emergency services based on the registered location of the number — India (112), UK (999/112), US (911), UAE (999). Location registration is configured during provisioning.
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