Kannel SMS Gateway Alternative: Switch to Ozeki Without Changing Your Applications

Why Users Look for a Kannel Alternative

Kannel is mature and battle tested, but its architecture reflects the era in which it was built. The following limitations are the most common reasons our customers cite when they decide to evaluate an alternative:

• Configuration happens in text files. Every SMSC connection, route, and user account is defined in kannel.conf. A single syntax error can prevent the gateway from starting, and every change requires a restart.
• There is no real administrative interface. The HTTP admin server on port 13000 exposes a status page and a few commands, but you cannot configure connections, manage users, or browse messages from a browser.
• Deployment is Linux centric. Official builds target Linux and Unix systems. On Windows you must rely on Cygwin, which is unsupported and fragile in production environments.
• SMPP support is one sided. Kannel can connect to an SMSC as an SMPP client, but it cannot operate as an SMPP server for your own customers, partners, or internal business units.
• Database messaging requires an extra component. Sending and receiving messages through SQL tables calls for sqlbox, a separate daemon with its own configuration and failure modes.
• Support is community based. There is no vendor behind your deployment, no service level agreement, and no guaranteed fix for the version you run.

Keep Your Applications: The Kannel Compatible API

This is the detail that makes the switch practical. Ozeki SMS Gateway implements the Kannel sendsms HTTP interface. Your applications, scripts, and integrations send messages using the same request format, the same parameters, and the same response behaviour they use today.

A typical Kannel request looks like this:

http://127.0.0.1:13013/cgi-bin/sendsms?username=myuser&password=secret&to=%2B36201234567&
from=MyApp&text=Hello+world&dlrmask=3&dlrurl=http%3A%2F%2Fmyapp.example.com%2Fdlr%3Fid%3D123%26status%3D%25d

To send the same request through Ozeki, you only change the host and port in the base URL to point to your Ozeki server. The request parameters are accepted as they are:

• username and password for authentication
• to and from for the recipient and sender addresses
• text for the message body
• udh for user data headers used in concatenated and binary messages
• coding and charset for GSM 7 bit and UTF 8 text
• dlrmask and dlrurl for delivery report callbacks
• pid, mclass, and other optional message flags

Delivery reports are forwarded to your get-url callback in the same name value pair format Kannel uses, and the familiar success response is returned as well. In practice, migration on the application side comes down to a single change: the base URL of the SMS gateway. Authentication, message submission, and report handling all stay exactly as they are. The full parameter reference is available on our Kannel compatible API page.

What You Get When You Switch

Beyond compatibility, Ozeki adds the capabilities Kannel users ask for most often:

Web Based Configuration GUI

Install, configure, and operate the entire gateway from a browser. SMSC connections, routing rules, users, and permissions are managed through forms instead of config files. Live logs, message archives, and delivery statistics are visible in the same interface.

SMPP Client and SMPP Server

Connect to carrier SMSCs as an SMPP client with transmitter, receiver, or transceiver binds, and run your own SMPP server to serve customers and partners. TLS encryption is supported on both sides.

Built In Database Integration

Send SMS by inserting a row into a database table and receive SMS by polling another table. MySQL, Microsoft SQL Server, PostgreSQL, and Oracle are supported directly, with no additional component to install or maintain.

Reliable Delivery Reporting

Every message status is stored and searchable. Reports can be forwarded to your application over HTTP, written to SQL databases, or inspected in the GUI, so lost delivery reports stop being a daily concern.

Windows and Linux

Ozeki runs as a native Windows service and on Linux. GSM modem connectivity works out of the box through COM ports on Windows and serial devices on Linux, with a driver wizard to simplify setup. Alongside the Kannel compatible API, SMPP, UCP/EMI, CIMD2, HTTP SMSC, and GSM modem AT command connections are all supported.

Kannel vs Ozeki SMS Gateway: Comparison Snapshot

The table below summarizes the differences that matter most in day to day operation:

A more detailed analysis is available on our Kannel vs Ozeki comparison page.

Who Should Switch, and Who Should Stay

An honest evaluation helps you decide. Ozeki SMS Gateway is a strong fit if you:

An honest evaluation helps you decide. Ozeki SMS Gateway is a strong fit if you need to run or administer the gateway on Windows, want a graphical interface instead of config file editing, must operate as an SMPP server rather than only an SMPP client, store messages or delivery reports in SQL databases and want this built in, require commercial support with defined response times, or prefer a vendor-maintained product with regular releases.

Kannel remains a reasonable choice if you run a Linux-only environment, your team is comfortable with config files and command-line tools, your traffic patterns are stable, and community support is acceptable for your organization. If any of the points above describe your situation, switching removes daily friction without touching your core setup.

Migration Is a Predictable, Low Risk Process

Because the API is compatible, you can move in controlled steps instead of a risky big bang cutover:

1. Install Ozeki SMS Gateway on Windows or Linux.
2. Recreate your SMSC connections (SMPP, HTTP, GSM modem) and routing rules.
3. Create user accounts that mirror your Kannel sendsms users.
4. Send a test message with the same URL your applications use today and confirm the delivery report arrives.
5. Run both gateways in parallel, then switch traffic over to Ozeki.

The complete procedure, including a kannel.conf to Ozeki settings mapping and a rollback plan, is described in our Kannel to Ozeki migration guide.

Try Ozeki SMS Gateway with Your Existing Kannel Applications

You can evaluate every feature described on this page using the free trial of Ozeki SMS Gateway. Download it, install it on Windows or Linux, and connect your first application with its existing Kannel request format. If you have questions during evaluation, our support team is happy to help, and the API compatibility documentation covers every parameter in detail.

• Download the free trial
• View the Kannel compatible API documentation
• Read the step by step migration guide