Connectivity

Router-based VPN and SBO connectivity for stable VoIP media

An encrypted, stable transport between your gateway and our routing platform, configured on the router rather than on every endpoint. For operators whose call quality problems are not routing problems at all; they are transport problems.

Configured once on the router, not on every device
Encrypted transport for signalling and media
Set up and tested with an engineer on the call

Ask about VPN connectivity See the specification Router-level setup

At a glance Router-level configuration at your edge Encrypted tunnel carrying SIP signalling and RTP media Common business router and gateway platforms Configured and tested with our engineer on the call

Specification

The numbers, up front

Destination-level coverage

Deployment: Router-level configuration at your edge
Transport: Encrypted tunnel carrying SIP signalling and RTP media
Compatibility: Common business router and gateway platforms
Setup: Configured and tested with our engineer on the call
Monitoring: Tunnel state and packet-loss alerting
Best for: Operators with unstable or restricted local transport
Typical volume: Sized against your concurrent channel count

What you get

What a proper tunnel fixes

Jitter, one-way audio and calls that drop at the same time every evening are usually the network between you and the platform, not the termination route.

Encrypted end to end

Signalling and media travel inside the tunnel rather than across the open internet in the clear.

Stable path for RTP

A consistent transport reduces the jitter and packet loss that produce choppy audio and dropped calls.

One configuration, every endpoint

Configured on the router, so phones, gateways and softphones behind it are covered without touching each one.

Tunnel health monitored

Loss and tunnel state are alerted on, so a degrading link is visible before it becomes a call-quality complaint.

Works with what you already have

Common business routers and VoIP gateways, configured with an engineer rather than a PDF.

Support that will look at your PCAP

When quality is disputed we will read the capture with you instead of pointing at your ISP.

Most “route quality” complaints are transport complaints

The diagnostic is simple. If audio quality varies by destination, suspect the route. If it varies by time of day, by site, or by which office the agent is sitting in, suspect the transport between you and the platform.

Transport problems have a recognisable signature:

Jitter. Packets arriving unevenly, producing choppy or robotic audio.
Packet loss. Gaps and clipping, worse under load.
One-way audio. Almost always NAT or firewall behaviour rather than the far end.
Evening degradation. Local contention on a shared link, not the terminating carrier.

What the tunnel does

It gives signalling and media a single, encrypted, monitored path between your edge router and our platform. Because it is configured on the router, every device behind it is covered, and stays covered when handsets are replaced.

We will tell you if you do not need it

If your problem is the route, a tunnel will not fix it, and selling you one would only delay the diagnosis. Send us a capture and we will read it with you before quoting anything.

Use cases

When operators ask for this

Call centres on unreliable local links

Where audio quality tracks the time of day rather than the destination.

Operators with restricted transit

Markets where direct VoIP transport is inconsistent or filtered.

Distributed teams behind one gateway

Branch offices and remote agents covered by a single router-level configuration.

Businesses with a policy against clear-text media

Encryption as a requirement rather than a nice-to-have.

Sites with frequent one-way audio

NAT and firewall interactions that a tunnel resolves cleanly.

Anyone tired of blaming the route

Isolating the transport is the fastest way to find out whether the route was ever the problem.

How it works

Getting a tunnel up

Describe your edge

Router model, connection type, concurrent channels and where the audio problems appear.
We scope the tunnel

Sizing, addressing and the configuration your specific router needs.
Configure together

An engineer on the call while it is applied, then a live test with real calls.
Monitor and review

Tunnel state and loss alerting, with a review once you have a week of real traffic through it.

Connect

How to connect VPN & SBO

Every method reaches the same routes, the same balance and the same reporting. Pick the one that suits how your platform is built.

Compare all connection methods

SMPP v3.4 bind

SMPP v3.4

An SMPP v3.4 bind is the standard way to move A2P SMS at volume. Transmitter, receiver or transceiver, with real…

Set up SMPP v3.4 bind

HTTP REST API

HTTPS / JSON

A straightforward HTTP REST API in JSON, for teams that would rather not run a persistent SMPP session. Same routes,…

Set up HTTP REST API

SIP interconnect

SIP / RTP

A SIP interconnect for voice termination, Voice OTP and TTS, with an engineer on the call for interop.

Set up SIP interconnect

IP authentication

IP allow-list

IP authentication instead of credentials: authenticate by source address, for platforms with fixed egress IPs.

Set up IP authentication

Coverage

Destination availability

Search for the destinations you care about. Anything not listed is usually available on request, capacity is added weekly.

Route availability by destination
Destination	Dial / MCC	A2P SMS	Voice OTP	TTS voice	Termination
Bangladesh	+880 · 470	Live	Live	Live	Live
India	+91 · 404 / 405	Live	Live	On request	On request
Pakistan	+92 · 410	Live	Live	On request	Live
Nepal	+977 · 429	On request	Live	On request	On request
Sri Lanka	+94 · 413	On request	Live	On request	On request
Indonesia	+62 · 510	Live	On request	On request	On request
Philippines	+63 · 515	Live	On request	On request	On request
Vietnam	+84 · 452	On request	On request	No	On request
Malaysia	+60 · 502	Live	On request	On request	On request
United Arab Emirates	+971 · 424	Live	On request	No	On request
Saudi Arabia	+966 · 420	Live	On request	No	On request
Oman	+968 · 422	On request	On request	No	On request
Qatar	+974 · 427	On request	On request	No	On request
Egypt	+20 · 602	On request	On request	On request	On request
Nigeria	+234 · 621	Live	On request	Live	On request
Kenya	+254 · 639	On request	On request	On request	On request
South Africa	+27 · 655	On request	On request	No	On request
Turkey	+90 · 286	On request	On request	No	On request
United Kingdom	+44 · 234	Live	On request	No	On request
United States	+1 · 310	On request	On request	No	On request

See 14 more destinations Show fewer

Why SisBird

Why configure it on the router

Router-level beats endpoint-level

Configuring each phone or softphone individually does not scale and breaks the first time someone replaces a handset.

It isolates the variable

With a stable tunnel in place, a remaining quality problem is genuinely the route, and then we can fix the right thing.

Same team, same account

Connectivity, termination and messaging on one relationship, so nobody gets to blame the other supplier.

Who runs these interconnects

Next step

Rule transport out before you blame the route

If your audio problems move with your location rather than your destination, the transport is the suspect. Tell us your setup and we will scope a tunnel.

1
You send the brief Destinations, monthly volume and the traffic type. Two lines is enough.
2
A routing engineer replies A costed plan with the route type stated per destination, usually within one business day.
3
You test on funded credit Same interconnects production runs on. No minimum term and no setup fee.

Or reach the routing team directly

Request a test route

For VPN & SBO. We reply within one business day.

Reply within one business day Free test credits on approval No spam, no reselling of your data

FAQ

VPN and SBO questions

What is SBO in this context?

SBO refers to a session-border-oriented connectivity arrangement in which the customer edge router establishes a managed, encrypted path to the provider platform, rather than sending SIP and RTP across the open internet. In practice it means one configured tunnel instead of per-endpoint workarounds.

Will this fix my call quality?

It will fix quality problems caused by the transport, jitter, packet loss, NAT-related one-way audio, and time-of-day congestion on your local link. It will not fix a poor termination route, and we will tell you which one you have rather than selling you a tunnel you do not need.

What equipment do I need?

A business-grade router or VoIP gateway you can configure. We will confirm compatibility with your specific model before quoting.

Is the media encrypted?

Signalling and media travel inside the encrypted tunnel between your edge and our platform. Encryption beyond that point depends on the onward interconnect.

How long does setup take?

Usually a single scheduled session with an engineer, once the scoping information is in. Complex multi-site setups take longer.

Do I have to buy routes from you as well?

No, though most customers do. The connectivity and the routing are separate services.

Read every wholesale routing question we are asked

Also available