MOR vs. M4 SBC

Not sure what the difference is between Kolmisoft Softswitches MOR, and M4 SBC?

Check this comparison table and choose which Softswitch meets your needs better.


Comparison Table: MOR and M4 SBC

Description MOR M4 SBC

Quick Summary

MOR is a feature-rich platform and is a great choice for those who want to offer various services under one platform and don’t have a huge call volume. It has a more extensive API and more small features that might be useful for you. M4 is more robust, more scalable, and can handle a few times higher call volume. It is a better choice unless you need some specific features that are available only in MOR, e.g. Recordings, Resellers, Spy real-time calls, or PBX features (IVR, Voicemail, Call Queues, or Ring Groups). Scroll down to see what’s supported and what is not.


MOR is based on Asterisk, which is one of the most popular frameworks for building communications applications. Even though Asterisk is flexible and allows many services under one platform, but it cannot handle high call volumes. M4 is based on Kamailio, SEMS and RTPEngine. The architecture of M4 is very robust, powerful and scalable. As a result, you can send huge call volumes with confidence and grow your business easily.


MOR single-server solution – up to 500 concurrent calls, up to 50 CPS (most of the time it’s closer to 20). MOR multi-server solution – up to 2000 concurrent calls, up to 100 CPS. M4 single-server solution – up to 500 concurrent calls, up to 100 CPS. M4 multi-server solution– up to 10 000 concurrent calls, up to 1000 CPS.

A list of the main features

MOR features M4 SBC features



Hardware requirements

Hardware requirements for MOR The same, just pay attention to the recommended NIC if you need over 700 concurrent calls.

Implementations (topologies)

MOR implementations M4 implementations

Documentation (manual)

MOR documentation M4 SBC documentation

Signaling protocols

SIP, H323, IAX2


Work behind NAT

MOR can work behind NAT. If your clients are behind NAT, it’s better to use MOR because it handles such cases better.

M4 can work behind NAT. However, it is not made to work with clients behind NAT. M4 does not handle local IPs placed in SIP headers. If you are planning to work with clients under NAT who use multiple registrations from one IP, use MOR.

Statement Of Account

MOR supports the Statement Of Account.

Auto-Dialer ✔️
Callback ✔️

Calling Cards ✔️

Spy real time calls ✔️
Resellers ✔️
Vouchers ✔️
PBX Functions (IVR, Ring-Groups, Voicemail, Music on Hold, Call Queues) ✔️
Recordings ✔️
Providers with Dynamic IP ✔️
TLS/SRTP support ✔️
Rate notifications ✔️

Wondering where to start?

Here are some useful resources: