Latest news with #IPMultimediaSubsystem
The Print
13 hours ago
- The Print
I got a call but the phone never rang—communications expert explains why this happens
There's a certain feeling I get in the pit of my stomach when I'm waiting for an important call to come through. You know the type – maybe a call from your boss, a potential new employer or news of a loved one who's due to give birth. Then it pops up – the missed call notification. But the phone never rang. What happened? In these situations, I usually stare at my phone, willing it to ring. I make sure – over and again – it's not on silent or 'do not disturb' mode. When the screen is out of my sight, I imagine I can hear the familiar ringtone. How do mobile calls work? When making a mobile call using 4G or 5G networks, the caller dials a number and their network operator (Telstra or OneNZ, for example) routes the request to the recipient's device. For this to work, both phones must be registered with an IP Multimedia Subsystem – or IMS – which automatically happens when you turn on your phone. IMS is the system that allows the combination of voice calls, messages and video communications. Both phones must also be connected to a 4G or 5G cell phone tower. The caller's network sends an invite to the recipient's device, which will then start to ring. This process is usually very fast. But as generations of cellular networks have evolved (remember 3G?), becoming faster and with greater capacity, they have also become more complex, with new potential points of failure. From phone failures to 'dead zones' Mobile phones use Voice over LTE (VoLTE) for 4G networks or Voice over New Radio (VoNR) for 5G. These are technologies that enable voice calls over those two types of networks and they use the above mentioned IMS. In some countries such as New Zealand, if either of these aren't enabled or supported on your device (some phones have VoLTE disabled by default), it may attempt to fall back to the 3G network, which was switched off in Australia in 2024 and is currently being phased out in New Zealand. If this fallback fails or is delayed, the recipient's phone may not ring or may go straight to voicemail. Another possibility is that your phone may have failed to register with the IMS network. If this happens – due to something like a software glitch, SIM issue, or network problem – a phone won't receive the call signal and won't ring. Then there are handover issues. Each cell phone tower covers a particular area, and if you are moving, your call will be handed over to the tower that provides the best coverage. Sometimes your phone uses 5G for data but 4G for voice; if the handover between 5G and 4G is slow or fails, the call might not ring. If 5G is used for both data and voice, VoNR is used, which is still not widely supported and may fail. Mobile apps introduce other potential problems. For example, on Android, aggressive battery-saving features can restrict background processes, including the phone app, preventing it from responding to incoming calls. Third-party apps such as call blockers, antivirus tools, or even messaging apps can also interfere with call notifications. Finally, if your phone is in an area with poor reception, it may not receive the call signal in time to ring. These so-called 'dead zones' are more common than telcos would like to admit. I live at the end of a long driveway in a well-covered suburb of Auckland in New Zealand. But, depending on where I am in the house, I still experience dead zones and often the WiFi-enabled phone apps will more reliably cause the phone to ring. What can I do to fix it? If your phone frequently doesn't ring on 4G or 5G there are a few things you can do: make sure VolTE/VoNR is enabled in your network settings restart your phone and toggle airplane mode to refresh network registration check battery optimisation settings and exclude the phone app you are using contact your carrier to confirm VoLTE/VoNR support and provisioning. But ultimately, sometimes a call will just fail – and there's very little an everyday person can do about it. Which yes, is annoying. But it also means you have a failsafe, expert-approved excuse for missing a call from your boss. Jairo Gutierrez, Professor, Department of Computer and Information Sciences, Auckland University of Technology This article is republished from The Conversation under a Creative Commons licence. Read the original article.
Time of India
30-05-2025
- Business
- Time of India
Tejas Networks CEO Anand Athreya quits
NEW DELHI: Homegrown telecom gear maker Tejas Networks Friday said its managing director and chief executive officer (CEO), Anand Athreya , has resigned from the company due to personal reasons. Athreya will be relieved from the position of MD & CEO effective close of business hours on June 20, 2025, Tejas Networks said in a regulatory filing. 'It has been my privilege to work at Tejas and I want to take this opportunity to thank you and the Board of Directors for their guidance and support. I also want to thank the Executive Team at Tejas for their leadership and the entire team at Tejas, for their warmth and "can do" attitude,' Athreya said in his resignation letter to N Ganapathy Subramaniam, chairman, Tejas Networks. Consequently, the Bengaluru-headquartered vendor has entrusted Arnob Roy , currently the executive director and chief operating officer (COO) of the company, with the additional responsibility of CEO, as per the regulatory filing. The development comes at a time when Bangalore-based Tejas, a part of the Tata Consultancy Services (TCS)-driven consortium, is deploying 4G and 5G radio access network or RAN for state-run Bharat Sanchar Nigam Limited (BSNL). Industry sources told ETTelecom that a few hiccups in BSNL's 4G network deployment, including IP Multimedia Subsystem (IMS) issues, led to his exit following a performance review by the telecom department (DoT). BSNL plans to deploy 1 lakh towers as part of its commercial 4G foray. Communications minister Jyotiraditya Scindia recently said that nearly 93,450 towers have been installed for the telecom carrier's 4G network. Athreya, who has over 27 years of experience, joined the homegrown vendor in 2023 from Juniper Networks. He was the executive vice president (EVP) & chief development officer of Juniper Networks since 2017 and had served as senior vice president of the Routing Business Unit for three years prior to that. He was with Juniper Networks from 2004 until November 2022.
