Comparison of VoWLAN basic Q & A five cellular/WLAN Modes

We plan to add VoIP to our mobile products, which adopt two modes: cellular and wireless LAN cellular/WLAN. When VoIP is used, is the interconnection capability of cellular/WLAN important? If so, which standard is better?

At this point, the most important aspect of the standard is the unified memory framework UMA), but it should be clear that the Mobile IP address and UMA are not comparable here. This may need to be explained as follows:

UMA is important because, for mobile phone manufacturers that use dual-mode channels for the use of authorized frequencies, the most difficult thing is how to maintain the number of mobile phone customers. In the early days, some service providers believed that licensing wireless VoIP technology would waste valuable time on the network. If someone asks, how can I complete the close integration of a local wireless network and a mobile network? The answer is: UMA

Using unauthorized frequency bands to expand the coverage area for users without losing valuable network user time became the final goal. Recent progress shows that mobile phone service providers have finally accepted the unauthorized frequency band technology and are trying to overcome the potential loss of time. This is good news for us. When voice services in the United States received network threats, bell quickly launched a very challenging DSL as a countermeasure to counter attacks similar to the current situation. That is to say, UMA is a proposed draft to standardize the transfer of GSM and GPRS to unauthorized frequencies such as 802.11, so that the service provider can know who is using it. As a result, the unauthorized band of UMA is used to cover areas that are generally not covered by cellular networks.

On the other hand, the use of mobile IP can also allow IP devices to freely pass through the IP network without distortion. This allows IP devices, PDAs, SIP phones, laptops, and so on to maintain the IP service without re-Logon or restart (even if it cannot be done completely, at least it is intended ).

We need to realize that the purpose of a mobile carrier is not to waste Wi-Fi wireless time, but also to realize that the mobile carrier is not an IP-based network. This means that when you go out of the house using Wi-Fi technology or Bluetooth and any of its unauthorized networks, from the infrastructure area with VoIP to the area without VoIP infrastructure.

Therefore, if you are developing a dual-mode mobile phone product, what you need is not to support mobile IP addresses, but to support network switching, such as switching from an IP network to a non-IP Network) and to maintain the GSM or GPRS Service protocol. You still have to hope for this in UMA.

1. VoWLAN: Implements VoIP technology application to import voice to WLAN
2. Discussion on the polling method in VoWLAN