What Is a Trunk Group? Understanding Elastic SIP Trunking

Trunking is a term used in telephony that refers to grouping multiple telephone lines into a single logical channel. This allows all the lines in the group to be connected to the same PBX extension or phone system.

It is the process of providing multiple logical trunk lines between two physical trunk lines. A trunk line is a single communication path between two points. A trunk can be either a physical circuit or a virtual circuit. A trunk may also refer to an optical fiber cable that connects two pieces of equipment.

Trunking is typically used to increase the capacity of a network by sharing trunk resources, such as a group of phone lines, for many more multiple users or services. For example, trunking provides multiple voice circuits over a single physical trunk in a voice network. One of the advantages of trunking is that it reduces the number of physical copper wires or fiber optic cables required to connect a PBX system to the public switched telephone network (PSTN).

In a data network, trunking provides multiple virtual circuits, also called logical links or tunnels, over a single physical trunk. Trunking improves network efficiency and utilization in both voice and data networks. It also provides redundancy in case of link or trunk failure.

What is Elastic SIP Trunking?

Session Initiation Protocol, or SIP, is a signaling protocol used in VoIP applications for initiating, maintaining, and terminating multimedia system communications sessions. SIP protocols are the standard for VoIP communications. An elastic SIP trunk carries several VoIP streams at once.

We can define elastic SIP trunking as a technology that enables a business to connect to the VoIP service provider over a traditional phone line and service. Elastic SIP trunking happens when an internet service provider (ISP) connects to a VoIP provider using a SIP trunk.

SIP trunking has become more common with the rise of VoIP services. The technology allows companies to move their traditional landline telephones over to their VoIP provider. Companies don't need to purchase new phones or hardware; they simply need to use the existing hardware and plug it into the ISP/VoIP company's network for them to communicate via VoIP. This is why many businesses make this switch, whether for cost-cutting purposes or for the convenience of having everything done in one place.

Trunk Groups and Trunks

A trunk group is a collection of trunks that connect a PBX system to the PSTN. A trunk is a single physical connection between devices, such as a PBX and a PSTN gateway. They are comprised of any combination of trunk types, including ISDN, SIP, SIP gateway, ENUM, and SwyxLink.

Trunk Types

Several types of trunks are used to connect a PBX system to the PSTN.

ISDN Trunk

ISDN trunks are used to connect a PBX system to an ISDN-compatible PSTN gateway. ISDN trunking offers many advantages, including support for multiple callers on a single line and improved voice quality.

SIP Trunk

SIP trunks are used to connect a PBX system to an IP-based PSTN gateway. SIP trunking offers many advantages, including support for multiple callers on a single line and improved voice quality.

SIP Gateway Trunk

SIP gateway trunks are used to connect a PBX system to an IP-based PSTN gateway. SIP gateway trunking offers many advantages, including support for multiple callers on a single line and improved voice quality.

ENUM Trunk

ENUM trunks are used to connect a PBX system to an IP-based PSTN gateway. ENUM trunking offers many advantages, including support for multiple callers on a single line and improved voice quality.

Trunk Group Routing Types

There are two primary types: failover and round-robin.

Failover

In failover trunk group routing, if one of the trunks in the group fails, the call is automatically routed to another working trunk in the group. This type of routing is typically used for critical calls, such as emergency calls.

Round-Robin

In round-robin trunk group routing, calls are evenly distributed among all of the working trunks in the group. This type of routing is typically used for non-critical calls.

Elastic SIP Trunking Advantages

Elastic SIP trunking has several benefits over traditional landline services.

One major advantage is lower operating costs and maintenance fees, as there are no longer any landline bills. Businesses also benefit from higher reliability due to the fact that ISPs have more backup options than traditional landlines.

The technology provides the ability to choose your own SIP trunking provider and switch providers if you're not satisfied with your current setup. You also gain the ability to easily port your existing number or get a new one if necessary.

Enhanced security is another key benefit, as you are no longer reliant on local phone wiring for protection from malicious attacks. Your data is transmitted via the Internet instead of through local phone lines, making it more secure against unauthorized access.

Users gain the ability to access a number of features, including voicemail, call forwarding, and caller ID. Easy setup and management means the SIP trunking provider handles all of the technical details for you.

A more reliable connection results from data being sent over multiple networks. If one network experiences congestion or goes down, your data can still be transmitted via another network.

Increased flexibility in terms of how you use the system and how many phones you need to connect to it gives businesses more options. For example, you can add or remove phones from your system without worrying about updating your landline phone service with your local phone company. This is especially useful for businesses with employees who frequently move around or work from home.

The ability to use multiple landline phones with the same phone number is especially useful for businesses that want multiple lines for different departments but don't want to pay for various phone numbers. For example, a company could have an 800 number for its sales department, a local number for its customer service department, and another for its marketing department. All three lines would be routed through your SIP trunking provider in this scenario, but each department would have its own extension. Sales could be extension 1001, customer service could be extension 1002, and marketing could be extension 1003.

Setting Up Trunks and Trunk Groups

To set up a trunk group, you will need to configure several components.

First, determine the type of routing, either failover or round-robin. To set up a failover trunk group, you configure one or more trunks in the group to be primary trunks. To set up a round-robin trunk group, you configure all of the trunks in the group to be equal priority.

Next, establish the routing order of the trunks in the group. The routing order is the order in which the trunks in the group will be used. For failover trunk groups, the primary trunks should be listed first, followed by the secondary trunks. For round-robin trunk groups, all of the trunks should be listed in any order.

Define the destinations for the trunk group. The destinations for a trunk group are the PBX extensions or phone numbers that the trunk group uses to connect to.

Configure the caller ID for the trunk group. The caller ID for a trunk group is the number or name displayed when calls are made from the trunk group.

Set the IP address or hostname of the PSTN gateway. The IP address or hostname of the PSTN gateway is used to connect the trunk group to the PSTN.

Finally, establish the QoS settings for the trunk group. The QoS settings for a trunk group determine the quality of the calls made from the trunk group.

Signalmash Elastic SIP Trunking Solutions

Signalmash Elastic SIP Trunking is a cost-effective, scalable, and reliable solution for connecting your PBX system to the PSTN. With Signalmash, you can easily add or remove trunks from your trunk group without reconfiguring your PBX system. Signalmash also offers a wide range of features, including call recording, caller ID blocking, and call forwarding.

If you're looking for carrier-grade voice without expensive service contracts, Signalmash is the way to go. You can connect your VoIP infrastructure to us in just minutes, and we have extensive direct connections to the networks you'll be calling. This means lower latency and high voice quality for you. And if security is a concern of yours, don't worry. We offer encryption options for signaling and media, so your communications will always be secure.

Signalmash offers elastic SIP trunking, which allows you to connect to mobile or landline phone numbers while utilizing your current VoIP infrastructure. The process takes only a few minutes to complete. As a result, you have limitless traffic capacity and can expand your services as necessary.

Signalmash offers straightforward elastic SIP trunking solutions for businesses that want to improve customer communications and reduce costs. We've been in the telecom industry for more than a decade and can provide solid SIP trunking solutions no matter what stage of growth your business is in.

Take charge of your communications using our on-demand cloud functionalities and elastic SIP trunk provisioning. Reach out to us today and talk to our experts. Let's help you make the most of your existing VoIP infrastructure.

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