Class 5¶
Document Metadata
Category: Infrastructure & Connectivity / PBX
Audience: Network Engineers, Administrators, Support Team
Difficulty: Beginner to Intermediate
Time Required: Approximately 20–30 minutes
Prerequisites: Active ConnexCS account with the Class 5 module enabled; familiarity with core Class 4 softswitch concepts (routing, SIP devices).
Related Topics: Class 4 Softswitch, Class5, Groups, IVR, Call Center, Conference, Voicemail
Next Steps: After reviewing the concepts below, configure your first Hunt Group or IVR, set up Call Queues for a call center use case, and test an end-to-end call flow through Class 4 into Class 5.
To fully appreciate the features of Class 5 services, it's essential to first understand Class 4 services and the key differences between them.
Class 4 vs. Class 5 Softswitch¶
What is a Class 4 Softswitch?¶
A Class 4 softswitch is primarily responsible for routing traffic from one carrier to another.
ConnexCS operates as a Class 4 softswitch.
The call never connects to ConnexCS itself; it simply passes through from Point A to Point B.
It can perform advanced routing functions, but does not handle call termination, media processing, or IVR.
What is a Class 5 Softswitch?¶
A Class 5 softswitch is responsible for call termination and media handling.
It can perform actions like:
- Answering calls
- Playing messages
- Providing voicemail and IVR services
- Unlike Class 4, a Class 5 switch manages end-user call features.
Key Difference Between Class 4 and Class 5 Softswitches
| Feature | Class 4 Softswitch (ConnexCS) | Class 5 Softswitch |
|---|---|---|
| Call Routing | ✅ | ✅ |
| Call Termination | ❌ | ✅ |
| IVR & Media Services | ❌ | ✅ |
| End-User Features | ❌ | ✅ |
What is Class 5 Cloud PBX?¶
A PBX (Private Branch Exchange) is a system that manages an organization's outgoing and incoming calls and enables internal communication within a business.
ConnexCS's Class 5 offering is a multi-tenant, cloud-hosted PBX that runs on the same globally redundant infrastructure as the Class 4 switch. The two are designed to work together: Class 4 handles routing and interconnect between carriers, while Class 5 handles the terminating applications — IVR, queues, voicemail, and conferencing — at the point a call reaches an end user.
Core Components¶
Hunt Groups (Ring Groups)¶
A Hunt Group rings a defined set of member numbers/extensions simultaneously when a call arrives for the associated group.
- Members are grouped by department or function.
- No load-balancing logic is applied — all group members ring concurrently.
- Suited to lower call-volume scenarios where simple distribution is sufficient, as opposed to Call Queues, which apply active balancing.
- Available as a standard feature across all plans.
See: Groups
Call Queues (ACD)¶
Call Queues (Automatic Call Distribution) extend beyond Hunt Group behavior by adding call-balancing, overflow, and escalation logic.
Supported configuration options:
- Team-based and skill-based agent grouping.
- Overflow designation — agents/teams that absorb excess call volume during high-traffic periods.
- Multi-skill queue membership, allowing an agent to belong to more than one queue.
- Smart routing — calls are only routed to currently available agents.
- Configurable wrap-up time between calls per agent.
- Trainee/new-agent designation to throttle call volume routed to a given agent.
- Real-time queue metrics and live call tracking, exposed to administrators.
All configuration changes are applied remotely without on-site intervention, consistent with the platform's hosted delivery model.
See: Call Center, Contact Center Setup
IVR (Interactive Voice Response)¶
An IVR presents callers with digit-based menu options. Keypad input is sent as a DTMF tone to the host system, which maps the received digit to a configured action (e.g., transfer to a queue, play a message, route to voicemail).
- Designed to handle high call volumes without requiring a live agent for routing or basic information delivery.
- Typical use cases: automated account/banking lookups, scheduling information lines, automated voting/polling lines.
See: IVR
Conference Bridges¶
Multi-party audio conferencing hosted on the Class 5 platform.
See: Conference
Voicemail¶
Per-extension voicemail, integrated with the other Class 5 call-handling components (Hunt Groups, Queues, IVR).
See: Voicemail
Architecture: Class 4 + Class 5 Together¶
Class 5 does not operate as a standalone termination point — it is deployed in combination with the Class 4 switch:
- Inbound traffic reaches the platform via the Class 4 layer (routing, carrier interconnect, ingress via AnyEdge where configured).
- Calls destined for a Class 5-hosted extension, queue, or IVR are handed off from Class 4 to Class 5 for termination.
- Class 5 answers the call and executes the configured application logic (IVR menu, queue distribution, hunt group ring, voicemail, or conference join).
This separation keeps routing/interconnect (Class 4) and call termination/application logic (Class 5) as distinct layers, while running on shared underlying infrastructure.