Wi-Fi Calling … Hello, hello, can you hear me?
Managing Director, Service Provider Architecture, EMEAR
Service Providers, Mobility, Thought Leadership
Wi-Fi calling (also known as Voice over Wi-Fi or Voice over WLAN) is a handy new feature that is now available on Apple iPhones running iOS8 and smartphones on Android 5.0 Lollipop. With Wi-Fi calling built into the phones, it doesn’t need a special app, and calls are routed over Wi-Fi automatically so it’s nice and easy for users. If you can’t get a cellular signal, especially when you are inside buildings where radio waves can’t get through the concrete, steel and glass, Wi-Fi calling can be a godsend.
But there are a few of things that businesses and mobile operators need to sort out before Wi-Fi calling can really work well.
For a start, mobile operators who want to support Wi-Fi calling for iOS 8 and Android 5.0 have to deploy a secure gateway (or Evolved Packet Data Gateway, ePDG) and IMS (IP Multimedia Subsystem) to their infrastructure. Many operators have already deployed IMS or have plans to in order to support Voice over LTE.
For consumers, routing calls over a home Wi-Fi network or public hotspot will work OK as long as the network isn’t too busy. But for business users, where a more robust system is required, there’s more work for the IT department to do before good quality voice over Wi-Fi in the workplace can be delivered.
Most enterprise Wi-Fi networks haven’t been built for voice calls. If you have a Wi-Fi network in your office, it’s most likely more than adequate for people connecting wirelessly from their desks, but if you start walking around with your wireless device, you could soon find your Wi-Fi call dropping. This could be lack of coverage, especially in areas where your IT department didn’t ever envisage the need to provide Wi-Fi – like stairwells, corridors or even in the toilets!
Moving from the vicinity of one Wi-Fi access point to another could also cause your voice call to drop unless your network supports seamless roaming. And voice applications need stronger Wi-Fi signal coverage compared to the majority of data-only applications. And if you are using Wi-Fi calling from a busy public Wi-Fi hotspot, you could be finding it hard to hear what your caller is saying.
IT departments will have to start taking voice over Wi-Fi into consideration when planning their next generation of Wi-Fi networks. Apart from Wi-Fi coverage and roaming, the handset has to establish a secure connection before a Wi-Fi call can be established. Enterprise IT teams may need to review their security policies to enable this new feature.
Ultimately, the real outcome we want is to make mobile access ubiquitous and seamless, so that uses don’t need to know if they are connected via Wi-Fi or cellular networks. Mobile operators see the deployments of small cells, miniature, low power versions of cell towers, into more indoor locations as part of this solution. We will also see them integrating their carrier Wi-Fi services with their cellular macro and small cell networks so that subscribers can get the best quality for voice and data anytime and anywhere.
Building Wi-Fi calling into the mobile device is certainly an interesting development. But for mobile users in the enterprise to take advantage of it, CIOs will need to understand the impact of voice on their mobile infrastructure.
Related announcement: Cisco Universal Wi-Fi helps Operators deliver High Definition Voice and Data over Wi-Fi