SS7 · DIAMETER · GMLC · LCS

Signaling protocols don’t fail where the spec says they will.

Protocol libraries and hands-on integration help for teams shipping SMS and location services over real SS7 and Diameter interconnects. Built from years spent debugging what carriers actually do, not just what the standard says they should.

See what we’ve learned
Protocol stack: live
MAP application
TCAP transaction
SCCP routing
M3UA adaptation
SCTP transport
The Problem

The spec is the easy part.

GSM MAP, TCAP, and SCCP are fully documented. What isn’t documented: which subsystem numbers a given carrier actually expects live, whether a response needs to route by point-code-and-subsystem or by Global Title, or that a decode step buried inside your protocol library silently returns nothing instead of throwing an error.

Every one of these looks fine in a lab. Every one of them breaks in production, quietly, with nothing pointing at the actual cause.

// four real failure modes, no error message in sight
> local subsystem registered at startup
silently overwritten by a reused internal ID
> SCCP response: NO_TRANSLATION_FOR_ADDRESS
the actual fix was skipping translation entirely, not adding a routing table
> message object decodes successfully
content stays empty until you explicitly ask for it
> GMLC location request parses and routes cleanly
the rejection came from carrier policy, not the protocol layer
Why Us

Real interconnects, not textbook protocol code.

We’ve already hit these failures

MO-SMS reception, routing-address mismatches, silent registration conflicts. Real production incidents we’ve debugged and fixed, not textbook scenarios.

We know where carriers deviate from spec

Undocumented subsystem numbers, routing quirks, and authorization gates that never show up until you’re live.

Transparent, industry-standard pricing

Our licensing mirrors the model the market already expects. No inflated premium just for working with us.

Flexible engagement, not lock-in

A protocol library license, project-based consulting, or a single paid session. Whatever actually matches your stack and timeline.

What We Offer

Three ways to work with us.

Protocol Library

SS7 (SCTP, M3UA, SCCP, TCAP, MAP) and Diameter building blocks, plus GMLC/LCS location-service support, hardened against real carrier behavior rather than just spec compliance.

Integration & Debugging

Stuck on a carrier interconnect that won’t complete? We diagnose against patterns we’ve already seen, not from scratch.

Book a Session

A paid, bookable slot with someone who’s actually done the debugging. Bring a specific problem, a config to review, or questions before you commit to a bigger engagement.

Available as licensed software, project-based consulting, or a paid session. We’ll figure out what fits once we know your stack.

Field Notes

A few things that don’t show up in any spec.

Sanitized, generalized lessons. No carrier names, no configs, no client details.

01

MO-SMS reception isn’t one operation.

Receiving a text for a service number usually means implementing two separate roles: answering the carrier’s own routing query, then separately accepting the actual delivery. Miss either half and the carrier’s system looks like it’s ignoring you, when it’s really just waiting on a question you never addressed.

02

The reply address matters more than the reply.

A perfectly valid response can go nowhere if it’s routed by Global Title when the carrier expects point-code-and-subsystem, or the other way round. No error, no warning. The message just never arrives.

03

One reused ID can silently break half your setup.

A subsystem registration reused the same internal reference across multiple entries. The first one worked. Every one after it silently failed. No exception, no log line, nothing pointing at the actual cause.

04

Decode before you trust the result.

Some protocol libraries hand back an object successfully but leave its actual content unpopulated until you explicitly ask for it. Skip that step and you get a message that looks received but reads as empty, right up until it crashes something downstream.

05

Authorization isn’t a technical layer.

A location request can reach the network, parse correctly, and come back with a clean, valid-looking rejection, because the carrier’s own authorization policy, not the protocol implementation, is what’s actually saying no. That’s a contract conversation, not a debugging session, and most teams spend weeks treating it as the latter.

06

SS7 and Diameter don’t share vocabulary, but they share failure modes.

The interface names change. An Application-ID instead of an Application Context, a Diameter peer instead of an SS7 point code. But the pattern underneath doesn’t: a routing decision that looks correct in isolation still has to match exactly what the node on the other end expects, or nothing about it visibly fails. It just goes nowhere.

How It Works

How engagement works.

01

Tell us your stack

Which carriers, which protocols, and where things are actually breaking, or where you’re starting from scratch.

02

We diagnose against real patterns

Most SS7 problems aren’t new. They’re a variation on something we’ve already seen and solved.

03

You get a working integration

Plus the documentation to keep it working after we’re gone.

Pricing

Priced to match the market you already know.

Our protocol-library licensing mirrors the standard per-node commercial model used across the industry, so you’re not paying a premium to work with us.

Protocol Library

SS7 & Diameter, licensed per node/VM. No TPS, CPU, or core limits.

$6,000 / node / year

Annual, support included

$15,000 / node

Perpetual, support included year one, then $2,250/node/year

Integration & Debugging

Diagnosing and fixing a stuck carrier interconnect: SS7, Diameter, or GMLC/LCS.

Custom

Scoped per engagement, once we know your stack

Book a Session

A single paid slot. Bring a config to review, a specific failure, or questions before committing to more. Pick a time, no commitment.

See full pricing & FAQ

Let’s talk about your SS7 stack.

We’re onboarding a small number of early partners.

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