Trunking in Telecom: Types, Benefits, and Examples

What is a Trunk?

A trunk is the communication channel that connects different switches or devices in a network. They can carry voice, data, or both. Trunks can be classified into different types based on the technology, protocol, or standard they use.

Some common types of Trunks are:

CO Trunk

A CO trunk is a traditional phone line trunk that provides connectivity by connecting a private branch exchange (PBX) to the central office (CO) of a telecom service provider. It is also called a direct trunk or a PSTN trunk. It can be analog or digital, carrying one voice channel per line.

PRI Trunk

A PRI trunk is a digital trunk that uses the Primary Rate Interface (PRI) protocol to provide multiple voice channels over a single line. Depending on the region, it is based on the T1 or E1 standard. A T1 trunk can carry 24 voice channels, while an E1 trunk can carry 30 voice channels. A PRI trunk also provides caller ID and other signaling information.

GSM Trunk

A GSM trunk is a trunk that connects a PBX to a GSM network using a GSM gateway device. It allows users to make and receive calls using mobile phone numbers and SIM cards. It can reduce the cost of mobile calls and provide backup in case of landline failure.

SIP Trunk

An SIP trunk is a trunk that uses the Session Initiation Protocol (SIP) to provide voice and data services over an IP network using VoIP technology. It can connect a PBX to an Internet Telephony Service Provider (ITSP) or Simply SIP trunking Service Provider or another SIP-enabled device. With SIP Trunking you can use voice calls, real-time video calls, and messaging multimedia together on a single line. As SIP Trunking works over the internet it doesn’t require any extra setup like a traditional phone line to set for new lines, so it is a highly scalable solution and thus provides the benefit of cost savings.

When you call from your telephone, your telephone system sends a digital signal to the service provider through the internet that connects your call further to the user on the other end.

So, Trunks are essential for providing network access, scalability, and efficiency in a telecommunication system. They enable the transmission of multiple signals over a single line, reducing the cost and complexity of wiring and equipment. Trunks also allow for interoperability and compatibility between different devices and networks, enhancing the quality and reliability of communication.

All Trunks Types can work on a single Hybrid Epabx System like Matrix Genx. Or if you want to use the latest technology like SIP Trunk only then you can use IP PBX Server like CoreIP 410 IP PBX System.