Source  Link: http://support.huawei.com/hdx/hdx.do?docid=SE0000750074&lang=en ----->Solutions/LTE

Background and Challenges:

The third generation mobile telecommunication technologies and the increasing popularity of smartphones have greatly driven user demands for mobile broadband services. The explosive growth of data traffic and the challenge of increasing network capacity require mobile carriers to upgrade their networks and increase the network transmission rate. The LTE technology is the best option for these carriers.

In the GSM/UMTS network, mobile voice services are the main source of income of carriers. In the LTE network, however, only packet switched (PS) services are provided and no circuit switched (CS) service is provided. After the GSM/UMTS network is evolved to the LTE network, carriers have an urgent demand for retaining the existing revenues from voice services, as well as improving subscriber loyalty and attracting more subscribers with high bandwidths and transmission rates of the LTE network.

Evolution of Huawei LTE Voice Solutions:

Figure 2 shows LTE network development stages, including hot spot coverage, consecutive coverage, and full coverage. Before full coverage of LTE network is implemented, the VoLTE solution implements the roaming, handover, and service continuity between 2G/3G and LTE networks for LTE subscribers.

Figure 2 LTE network development stages 

IMS/SRVCC is the final solution of voice over LTE, providing VoLTE services. To maximize carriers return on investment of the GSM/UMTS network, however, CSFB is used as a transitional option for the VoLTE solution. Before the VoLTE solution is fully deployed, the SRVCC solution needs to be deployed to ensure the continuity of voice services when subscribers are out of the coverage of LTE network, as shown in Figure 3.

As described in Table 2, Huawei provides two LTE-based voice solution evolution paths for carriers to choose based on actual situations.

Table 2 Network evolution paths

Evolution Path	Description
Evolution to IMS/SRVCC through CSFB (Path 2a+2b in Figure 3)	This solution applies when carriers use live GSM/UMTS networks to provide voice services for LTE subscribers in a short period and will smoothly upgrade their GSM/UMTS networks to the IMS network to provide voice services for LTE subscribers.
Evolution to IMS/SRVCC (Path 1 in Figure 3)	This solution applies when carriers use the IMS network to provide voice services for LTE subscribers.

Source  Link: http://support.huawei.com/hdx/hdx.do?docid=SE0000750074&lang=en ----->Solutions/LTE

Background and Challenges:

The third generation mobile telecommunication technologies and the increasing popularity of smartphones have greatly driven user demands for mobile broadband services. The explosive growth of data traffic and the challenge of increasing network capacity require mobile carriers to upgrade their networks and increase the network transmission rate. The LTE technology is the best option for these carriers.

In the GSM/UMTS network, mobile voice services are the main source of income of carriers. In the LTE network, however, only packet switched (PS) services are provided and no circuit switched (CS) service is provided. After the GSM/UMTS network is evolved to the LTE network, carriers have an urgent demand for retaining the existing revenues from voice services, as well as improving subscriber loyalty and attracting more subscribers with high bandwidths and transmission rates of the LTE network.

Evolution of Huawei LTE Voice Solutions:

Figure 2 shows LTE network development stages, including hot spot coverage, consecutive coverage, and full coverage. Before full coverage of LTE network is implemented, the VoLTE solution implements the roaming, handover, and service continuity between 2G/3G and LTE networks for LTE subscribers.

Figure 2 LTE network development stages 

IMS/SRVCC is the final solution of voice over LTE, providing VoLTE services. To maximize carriers return on investment of the GSM/UMTS network, however, CSFB is used as a transitional option for the VoLTE solution. Before the VoLTE solution is fully deployed, the SRVCC solution needs to be deployed to ensure the continuity of voice services when subscribers are out of the coverage of LTE network, as shown in Figure 3.

As described in Table 2, Huawei provides two LTE-based voice solution evolution paths for carriers to choose based on actual situations.

Table 2 Network evolution paths

Evolution Path	Description
Evolution to IMS/SRVCC through CSFB (Path 2a+2b in Figure 3)	This solution applies when carriers use live GSM/UMTS networks to provide voice services for LTE subscribers in a short period and will smoothly upgrade their GSM/UMTS networks to the IMS network to provide voice services for LTE subscribers.
Evolution to IMS/SRVCC (Path 1 in Figure 3)	This solution applies when carriers use the IMS network to provide voice services for LTE subscribers.

selim.hasan Posted on 2014-09-16 10:55

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Thanks!

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