Tech

Call Forwarding Glitches

Published on:

October 8, 2024

In the late 1980s, prank calls were a common form of entertainment but often caused confusion, similar to today’s call forwarding glitches. Recently, a client migrating to a new PBX system experienced disruptions when users mistyped numbers for call forwarding. While user errors are common, there's a bigger concern: calls being misdirected to emergency numbers or costly lines, especially since many VoIP phones lack security features. Solutions include restricting call forwarding to internal numbers, blocking access or allowing only specific, pre-approved numbers. Ultimately, balancing control over settings is essential to prevent glitches while keeping systems user-friendly.

Our story begins at the end of the 1980s, when music was great, there were no apps or even mobile phones, and kids were bored and always on the lookout for a good prank. So it happened back then I received a call from an esteemed colleague (or at least I thought it was an esteemed colleague). The conversation started with, “Yes, hello?” The reply was, “Yes, what do you want?” It turned out someone called us both up and then put the handsets together just to have us both speak to each other - this person was puzzled that we were connected! Ha ha! We still chuckle about it today.

Call forwarding can have a similar effect: when someone calls an extension, and the call is forwarded, that person is actually talking to someone else.

We recently migrated a client from an older PBX system. One of the features they are using with the new PBX is to redirect calls while they are away from the office. Though the PBX has many ways to handle this situation, the easiest way to explain it to their large number of users was to have them redirect calls as they had done with the previous PBX. 

It didn’t take long until the first trouble ticket opened. Looking at the change history for the extension quickly revealed the user had changed the call forwarding - there was a small typo in the number, however, and the number ended up unreachable. This caused a lot of grief, as that extension was frequently used and had now become unavailable.

It's easy to blame the user. That said, it’s quite easy to end up with a small typo that skews everything. The question is, what can the PBX do to avoid this problem? 

While examining the issue, more concerning scenarios arose: What if the user redirects the call to an emergency number? This would be quite a problem because the number is obviously called quite often. The emergency response center would receive a lot of calls from callers with no idea they had actually dialed an emergency number! 

What's even worse is most VoIP phones aren’t protected by any kind of authentication, so it’s easy for anyone with physical access to the device to set up call redirection. This is also a problem if the redirection is set to expensive numbers.

There are many settings on modern VoIP phones, and some of them make it possible to block access to call forwarding. This is unavailable with many models, however, and must be addressed on the PBX side. A simple way to address this is to disable the feature altogether; it’s easily done and, in many cases, there’s no need for users to change the call forwarding. 

Another simple way to block access to call forwarding is to restrict the feature to internal numbers. This will make it so the user can’t accidentally enter the wrong number. As a modification here, the administrator can just list the numbers to which the user can redirect calls. This actually makes perfect sense in many cases, but it requires a significant amount of work on the part of the administrator to set this up. 

Finally, it makes sense to restrict call forwarding to numbers the user can actually dial. This would be important when users aren’t allowed to initiate international calls or expensive numbers.

While we’re on it, we should discuss the DND question. Should users be permitted to set their devices on DND? In most cases this is perfectly fine - there are cases, however, where this is undesirable. 

And allowing DND can solve the problem that the user does not have to enter a redirect destination. In many cases, all the user wants is to redirect calls in absence. Most VoIP phones have a DND button, and then this task can be performed in a single button press. And there is no risk that the user will enter the wrong number.

Ultimately the question we’re trying to answer is how much control over settings do we want to give users in the user front end? VoIP phones actually expose only a small fraction of features, as compared to the user front end. If it makes sense to restrict what numbers can be set for call forwarding, how about changing an extension's name, title, department or location? The simple answer is the administrator also needs control over what fields are visible to the user. This should be available at extension, tenant and system levels. It’s the best way to prevent call forwarding glitches. Find out all about the Vodia call forwarding nodes.

About Vodia Networks

Vodia Networks, Inc. is a pioneering provider of B2B Cloud Communications Solutions catering to enterprises, contact centers and service providers. Vodia's PBX software boasts an extensive suite of business telephony features for on-premise and cloud-based systems and operates seamlessly across Windows, Linux or Mac platforms. Fully compliant with SIP industry standards, the Vodia phone system integrates effortlessly with a wide range of SIP-based devices and trunking providers, granting ultimate freedom in telephony. Vodia’s multi-tenancy platforms are compatible with an unprecedented number of technologies, including desk phones, softphones and APIs, for myriad third-party software and CRM systems. Our mission is to empower our partners and end-users with the world's best cloud PBX and personalized support to ensure their success at every turn. Visit Vodia on LinkedIn, X and YouTube. 

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