ULAP Networks

The Role of SBC in Telecom: A Guide

·

The Role of SBCs in Telecom

SBC in Telecom” refers to session border controllers in telecommunications.


As voice and video calls become part of everyday life, people expect them to be reliable, private, and secure. When we pick up the phone or join a video call, we don’t stop to think about how the connection works or what could go wrong. We simply expect it to work.

While most users only think about things like speed, pricing plans, or network coverage, the hidden systems inside a telecom network matter just as much.

Customers don’t want to wonder why a call dropped, why the quality was poor, or how a scammer gained access. Those concerns should already be taken care of behind the scenes.

That is exactly the role of the Session Border Controller (SBC).

Why Telecoms Use SBCs

An SBC is an unseen safeguard that keeps calls and data sessions secure and dependable. If a telecom network is like a highway, the SBC is the checkpoint that ensures traffic flows safely, only trusted vehicles pass through, and rules are followed to avoid accidents. In technical terms, it protects against attacks, translates between different systems, and maintains the quality of voice and video.

In short, a strong SBC is what makes reliable communication possible.

How SBC in Telecom works

session border controller diagram

Every call or data session begins and ends on a device, and the telecom network must protect both those endpoints and the path between them. A Session Border Controller does this by managing five key functions:

  1. Admission: Decides which sessions can enter the network.
  2. Authentication: Confirms the identity of users and devices.
  3. Security: Shields calls from fraud, spam, and attacks.
  4. Optimization: Balances bandwidth and ensures clear call quality.
  5. Routing: Directs traffic to the right destination.

SBC in Telecom: Provider Use to User Benefit

These functions benefit both providers and users. For operators, SBCs ensure compliance, prevent fraud, reduce costs, and support flexible services. For users, they mean reliable connections, clear conversations, safe sessions, and smooth communication across different networks.

8 3

SBC in Telecom Setup

When telecom providers set up a Session Border Controller (SBC), they have two main choices: hardware or software. Deciding between them is one of the most important steps in designing a reliable telecom system.

Hardware For SBC in Telecom

Early SBCs were built as dedicated hardware appliances, installed in data centers and connected directly to telecom lines. They delivered strong performance and reliability, making them a trusted choice for critical communication systems.

However, they are costly to purchase and maintain, and scaling often means buying more boxes that consume space, energy, and staff resources.

Hardware SBCs are still used today for high-performance or security-sensitive environments, but they lack the flexibility modern operators demand.

You can read more about SBC hardware here: SBC Hardware: Function, Costs, and Alternatives

Software For SBC in Telecom

Most telecom providers now prefer software-based or virtual SBCs.

These run on standard servers or in the cloud, where sessions are handled virtually instead of through physical ports. This makes it simple to scale up or down without heavy hardware investments.

Software SBCs are also more agile: new features, updates, or extra capacity can be deployed quickly, making them ideal for fast-changing telecom networks. With lower costs and greater flexibility, software SBCs are becoming the industry standard — especially when offered as SBCaaS (SBC as a Service).


Session Border Controllers may be invisible to end users, but they are critical for secure, reliable communication in modern telecom. Whether deployed as hardware or software, SBCs ensure calls, video, and data sessions flow smoothly across networks.

Looking ahead: In a future article, we’ll explore how different SBC providers deliver these functions — and what to consider when choosing the right solution for your network.

ulap R 3

ABOUT ULAP NETWORKS

ULAP is a global leader in intelligent cloud solutions, bridging advanced and emerging markets across 113 countries. Through its Smart Cloud Network, ULAP delivers agile, secure, and efficient solutions like SD-WAN and SBC-as-a-Service to global clients, including companies in the Fortune 500.

Guided by its core values, ULAP is committed to forward-thinking innovation, ethical business practices and fair competition.

ulap R 3

Ready to learn more about intelligent global network solutions?

We provide you a cost-effective intelligent solution that enables you to fulfil your business initiatives. Our dedicated team of professionals will strive to ensure that your overall experience with ULAP is frictionless.

"*" indicates required fields

This field is for validation purposes and should be left unchanged.
ULAP Networks

ULAP Networks © 2025