5G SA vs 5G NSA: What Are The Differences?

5G SA vs 5G NSA: What Are The Differences?

5G SA vs 5G NSA: What Are The Differences?

October 19, 2020

Introduction

For leading mobile network operators (MNOs), 5G is mainly about offering high-speed connectivity to consumers, on devices that support fifth-gen network services. To smoothly transition from the existing legacy core to 5G, MNOs have two pathways: Non-Standalone (NSA) or Standalone (SA) architecture. And while they are both means to the same end, NSA and SA are structurally and functionally different.

NSA allows operators to leverage their existing network investments in communications and mobile core instead of deploying a new core for 5G. 5G Radio Access Network (RAN) can be deployed and supported by the existing Evolved Packet Core (EPC), lowering CAPEX and OPEX. To further lower network operating costs, operators can adopt the virtualization of Control and User Plane Separation (CUPS) along with software-defined networking (SDN). These initial steps will help quickly unlock new 5G revenue streams and offer faster data speeds.

5G SA is a completely new core architecture defined by 3GPP that introduces major changes such as a Service-Based Architecture (SBA) and functional separation of various network functions. Its architecture has the definite advantage of end-to-end high-speed and service assurance, particularly useful for MNOs who are set to commence new enterprise 5G services such as smart cities, smart factories, or other vertically integrated market solutions. The deployment model enables the rapid introduction of new services with quick time-to-market. However, it means additional investment and complexities of running multiple cores in the network.

Architecturally, NSA includes a new RAN, deployed alongside the 4G or LTE radio with the existing 4G Core or EPC. 5G SA, on the other hand, includes a new radio along with the 5G Core (5GC), comprising completely virtualized cloud-native architecture (CNA) that introduces new ways to develop, deploy, and manage services. 5GC supports high-throughput for accelerated performance than the 5G network demands. Its virtualized service-based architecture (SBA) makes it possible to deploy all 5G software network functions using edge computing.

5G software network functions using edge computingAn overview of 5G SA and 5G NSA deployment options (Source: GSMA) 

5G Standalone (SA) vs 5G Non-Standalone (NSA)

5G SA Architecture

According to a survey, 37% of MNOs will deploy 5G SA within two years; 27% of operators plan to deploy 5G SA within 12 to 18 months with an additional 10% increase within 24 months. 5G SA architecture will allow operators to address the fifth generation of mobile communications, including enhanced mobile broadband, massive machine-to-machine communications, massive IoT, and ultra-low latency communications.

Standalone 5G NR comprises a new end-to-end architecture that uses mm-Waves and sub-GHz frequencies and this mode will not make use of the existing 4G LTE infrastructure. The SA 5G NR will use enhanced mobile broadband (eMBB), Ultra-Reliable and Low Latency Communications (URLLC), and huge machine-type communications (mMTC) to implement multi-gigabit data rates with improved efficiency and lower costs.

5G SA also enables more advanced network slicing capabilities, helping operators rapidly transition to both 5G New Radio (NR) and 5G as the core network. Network slicing, URLLC, and mMTC bring ultra-low latency along with a wide range of next-gen use cases like remote control of critical infrastructure, self-driving vehicles, advanced healthcare, and more. However, the NR advanced cases are not backward compatible with the EPC, which is the framework that provides converged voice and data on a 4G LTE network. The level of reliability and latency that 5G provides will be indispensable for handling smart-grid control machines, industrial automation, robotics, and drone control and coordination.

5G NSA Architecture

NSA 5G NR is considered as the early version of SA 5G NR mode, in which 5G networks are supported by existing LTE infrastructure. It fundamentally concentrates on eMBB, where 5G-supported handsets and devices will make use of mmWave frequencies for increased data capacity but will continue to use existing 4G infrastructure for voice communications.

NSA helps MNOs launch 5G quickly for eMBB to get a competitive edge in the telecom market. NSA also helps leverage its existing LTE/VoLTE footprint to maximize the LTE installed base and boost capacity while increasing delivery efficiency. It will not support network slicing, URLLC, and mMTC, but its higher broadband speeds will enable services such as video streaming, augmented reality (AR), virtual reality (VR), and an immersive media experience.

Non-Standalone 5G NR will provide increased data-bandwidth by using the following two new radio frequency ranges:

  • Frequency range 1 (450 MHz to 6000 MHz) – overlaps with 4G LTE frequencies and is termed as sub-6 GHz. The bands are numbered from 1 to 255.
  • Frequency range 2 (24 GHz to 52 GHz) – is the main mmWave frequency band. The bands are numbered from 257 to 511.

Technical Differences between 5G SA and 5G NSA

The main difference between NSA and SA is that NSA provides control signaling of 5G to the 4G base station, whereas in SA the 5G base station is directly connected to the 5G core network and the control signaling does not depend on the 4G network. In simple terms, NSA is like adding a solid-state drive to an old computer, which can improve the system’s performance, while SA is like replacing it with a new computer that has newer technologies and optimum performance.

Some benefits include:

  • NSA is extremely low in cost compared to SA.
  • NSA eases 5G network deployments as it reuses existing 4G facilities, thus allowing rapid time to market for 5G mobile broadband.
  • With NSA, the deployment is faster and time-to-market is lower, as 4G locations can be used to install 5G radio. SA requires building 5G base stations and the back-end 5G core network to fully realize the characteristics and functions of 5G.
  • SA involves a 5G core with SBA for scalability and flexibility to deliver a superfast network with ultra-low latency for advanced 5G use cases.

5G Usage Scenarios in NSA and SA Operation

The requirements of 5G NR for the SA provide a complete set of specifications for the 5G core network that goes beyond NSA. The three major usage scenarios defined for 5G by the 3GPP and GSMA include:

  1. Enhanced mobile broadband (eMBB)
  2. Ultra-reliable and low latency communications (URLLC)
  3. Massive machine-type communications (mMTC)

Enhanced Mobile Broadband with 5G Major 5G usage scenarios

The Future of 5G Includes NSA and SA

Early adopters of 5G primarily focus on NSA deployments as they compete to deliver 5G speeds with a quick time to market. These MNOs can move to SA-based architecture over a period of time, which most plan to do. NSA deployment remains a mainstream solution given its ability to handle both 4G- and 5G-based traffic, keeping these early adopters ahead of their competition as they undertake their network transformation. 5G devices are not widespread so the need for SA-based architecture is still nascent.

In the future, the convergence of NSA and SA will help operators move to a full 5G network. A complete virtualized 5G architecture will allow MNOs to migrate and choose varied functionalities of their existing NSA solution to the 5GC platform, as new 5G services are launched, allowing them to monetize their investment gradually rather than move all at once and enabling them to recover their costs over time.

Although SA is a more mature network architecture compared to NSA, NSA will continue to be the more commonly chosen path to 5G. All NSA single-mode 5G phones launched this year or early next year will be valid for a decade, and as SA architecture permeates, more and more 5G SA devices will be in our homes and businesses.

Rajesh Mhapankar

Rajesh Mhapankar

Director, Innovations

A seasoned professional, technologist, innovator, and telecom expert. With over 20 years of experience in the software industry, Rajesh brings a strong track record of accelerating product innovations and development at Alepo. He supports the company’s mission-critical BSS/OSS projects in LTE, WiFi and broadband networks, including core policy, charging, and control elements.

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Native WiFi Calling Gaining Ground on OTT Calling

Native WiFi Calling Gaining Ground on OTT Calling

Native WiFi Calling Gaining Ground on OTT Calling

4th of October 2017
Making calls over WiFi is no new thing to us. It’s hard to even remember the days before online video and chat OTT services like Skype and WhatsApp. However, what was once an experience distinct from cell phone calling, requiring separate software and logins is now becoming integrated into standard cellular service, altering how people make their WiFi calls.

The Early Days of Native VoWiFi

Apple’s iPhone started the change. When FaceTime launched 7 years ago, the shift started to happen almost overnight. Like iMessage, if you were connected to WiFi, you could make FaceTime video and voice calls without using your cellular data or voice plan. The benefit to subscribers was immense, considering most people spend the majority of their time connected to WiFi. The only disadvantage of FaceTime and iMessage? It only worked between Apple devices.

Today’s Native VoWiFi

Fast forward to today. Now, calls can be made over WiFi to any other device, be it another cell phone or a landline, just by calling as you would for any call through the device’s native dialer. What does this mean? Gone are the days of WiFi calling’s dependence on OTT apps or the need to have an Apple device! For operators, instead of a threat, WiFi calling actually presents a unique opportunity for real innovation. Plus, if operators implement VoLTE, this offers users a truly seamless handoff from cellular to WiFi calls, presenting an extra incentive to not use OTT apps, as they can remain mobile, even when calls began over WiFi.

Native WiFi Calling vs OTT WiFi Calling

OTT (over-the-top) VoIP WiFi calling is a cloud-based service that requires a separate client and typically does not allow for mobility. Carrier WiFi calling, on the other hand, is integrated with the mobile carrier’s network, uses the native dialer on the handset, and is generally an extension of the mobile subscription plan, and typically includes a seamless mobile experience.

Native vs OTT WiFi Calling

 Native WiFi CallingOTT WiFi Calling
DescriptionUsers’ devices directly access IMS networks to perform voice services with few changes in the core network. Calls will glide from cellular to WiFi and back again without any interruption in service.This is similar to what Skype calling or a voice call over WhatsApp offers, which works great until you leave the WiFi hotspot. Calls will drop as soon as you are out of WiFi range. It is unavoidable for calls to drop since there is no seamless handoff from cellular to WiFi.
Advantages
  • Unified dialing/message interface. No need to fire up a third party app.

  • Voice service continuity can be achieved utilizing the same phone number (seamless handoff).

  • Same QoS maintained as that in VoLTE.

  • Easy set up on the user’s device (just turn on WiFi calling option).

  • Only IMS network remodeling required.
  • Easy to deploy, no IMS or additional network infrastructure necessary

  • From a user's perspective, all he/she needs to do is download the app, register and it’s ready to go.
Limitations
  • An ePDG needs to be in place.

  • Limited user devices support WiFi calling, currently the latest models of iPhone, Samsung, LG, HTC to name a few (this list is naturally going to get bigger over the time)
  • Not a carrier-class voice solution, thus less reliable.

  • Lack of service support

  • QoS not guaranteed (no ownership of customer experience).

  • No general and regulatory services provided. (i.e. Emergency calls).

  • No standards defined.

Native WiFi Calling Benefits

Overall, native WiFi calling can be a win-win solution for both subscribers and operators. According to an Ericsson Consumer Lab study1, the key reasons users are interested in native WiFi calling are those shown in the chart below. Users value the fact that they do not need to download any extra apps or perform any additional logins. They also appreciate that their VoLTE calls get seamlessly handed over once they come in the range of WiFi, and vice versa. But, the bigger drivers are extended coverage and eliminated roaming charges. Gone are the days of going out on the back patio to get a better signal because the inside of your house is a dead zone. Or avoiding calls while traveling abroad for fear of the massive roaming charges you might rack up.  For carriers, these subscriber benefits correspond with distinct business gains, such as reduced CAPEX and OPEX, new revenue streams, competitive advantage, improved customer experience, increased international service, improved quality of experience, and first-mover advantage.

Voip wifi calling

Conclusion: Watch Your Back, OTT!

With all the benefits of native WiFi calling, it’s easy to see why OTT apps are losing their stronghold on the WiFi calling market. It will be interesting to see how the OTT market changes over the next few years to try to remain competitive and relevant!

Learn more about WiFi calling with Alepo’s white paper.

Ryan Gray

Ryan Gray

Partner and Sales Director

Ryan is intrigued by where telecommunications will go in the next few years. As a Partner and Sales Director, she’s been exposed to many aspects of the industry in different technologies and markets. When she’s not speaking in telecom acronyms, you can find her traveling the world, skiing the Colorado Rockies or doing DIY projects on her home.

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WiFi Calling vs. WiFi Offload

WiFi Calling vs. WiFi Offload

WiFi Calling vs. WiFi Offload

    20th of September 2017        

While on a call the other day, it occurred to me that even highly knowledgeable people in the telecommunications industry have a difficult time deciphering the differences between WiFi calling and WiFi offload. The two types of technology are both constantly talked about, and often in relation with one another, but somewhere along the way, the defining line of what distinguishes them has become blurred. I’ll try to clear up this confusion so that you can make clearer decisions when the time comes for you to consider WiFi strategies. To start, let’s explore WiFi Offload…

The (Abbreviated) Origins of WiFi Offload

Years ago, the industry was hit with a pair of realizations: 1) the current cellular infrastructure wasn’t going to be able to handle rapidly growing data usage and 2) WiFi is a much cheaper and easier network to build than cellular. So, the solution of utilizing WiFi to handle cellular traffic was born.

So, Just What is WiFi Offload?

Getting slightly technical, WiFi Offload uses EAP-SIM/AKA technology, to automatically “offload” cellular users onto a recognized WiFi network as soon as they come in the range of the hotspot. Offload is as straightforward as it sounds. The EAP-SIM/AKA authentication compares the SIM information in a user’s phone to the information in the mobile provider’s home subscriber server (HSS). If the SIM credentials match, it kicks a user off of the cellular network and puts them on the WiFi network, without any action from the end user. The experience is seamless for the user and they shouldn’t even notice that their phone has been offloaded onto WiFi. This is similar to the way that your phone automatically connects when you come within range of your home WiFi. The difference is that the user is automatically offloaded onto hotspots they have never connected with before, and there is no need to enter a password or key.

Why Mobile Network Operators are Interested

Offload helps operators ease network congestion and improve the quality of service their customers receive in high-density areas. Often, operators will put hotspots in crowded public locations, like a stadium or downtown area, where network congestion is high. Operators can also “expand” their network coverage, installing hotspots in areas with poor cellular coverage, instead of installing a microcell. The main benefit here? WiFi is MUCH cheaper.

If those benefits weren’t enough, operators can form partnerships with other businesses/ISPs/MNOs in the area, or worldwide, to let their subscribers automatically offload onto the business/ISP/MNO WiFi networks as well. The advantage here is that operators can expand their network without making any investment in hardware. Plus, they can gain revenue by letting other operators’ customers roam onto their WiFi network.

Depending on their business model, operators utilizing WiFi offload can either continue to charge customers at the same rate they would for cellular data or provide WiFi access free of charge. Regardless of charging models, operators and customers gain significantly from utilizing WiFi Offload.

Operator Gains:

  1. Free up space on the cellular network, especially useful in high density/congested areas
  2. Provide a higher-quality of service (QoS) to all users
  3. Form partnerships to expand their network coverage without investing a dime in hardware

Customer Benefits:

  1. Save cellular data if their operator doesn’t charge them for the WiFi use
  2. A boost in QoS makes streaming movies and video chatting much better, and customers won’t experience the frustration of not being able to send a Snapchat or post to Instagram when they’re at the biggest football match of the season.
  3. Say goodbye to dead zones! Customers will love the increase in coverage locally and/or worldwide.

So, What’s WiFi Calling?

WiFi calling is related to offload, but not quite the same. So, now you have a network of WiFi hotspots around the city, and you are offloading users onto it. Great! Now the issue is, how will a user choose to make a call?

The Rise of OTT Apps

Traditional mobile phones could only make calls on voice networks (2G and 3G). To fill this void, OTT apps like Skype and Whatsapp hit the market with high-quality calling and messaging enabled over any data connection, LTE or WiFi. Operators then started to see a huge decline in the revenue they used to get from voice calling and text messaging. Users realized that they could save their minutes and messages by simply calling and messaging with their OTT apps. Operators were forced to focus on data as their key service offering. Finally, voice over LTE (VoLTE) was introduced and calls could be made over a data connection. But, calls still couldn’t be made on WiFi. But it was only a matter of time. Today, all new phones hitting the market are WiFi calling enabled too, meaning a user can make a call on WiFi with their phone, without using an OTT app. This is often referred to as VoWiFi. But, native VoWiFi calls (not through an OTT app) will not work on a WiFi calling enabled smartphone unless the operator makes the required changes in their network. This is what a WiFi calling solution provides. So, until the operator changes out their network, their users will have to use an OTT app to make VoWiFi calls.

The Fall of OTT Apps

The time has finally come for operators to take back what they have lost from OTT apps. When an operator has a network that supports both VoLTE and VoWiFi, they can provide a seamless experience to their users. So, when a user is on a WiFi call and they move out of range of the WiFi hotspot, the call is seamlessly connected to the LTE signal and the call can continue uninterrupted, and vice versa if they come back into range of a hotspot. Because all new handsets are WiFi calling enabled, this functionality is going to become progressively important as calls are increasingly made on a WiFi or VoLTE connection, as opposed to the traditional voice networks. The fact that operators are already decommissioning their 2G and 3G networks is an indication that all calls in the future will be on LTE data, which is going to increase the need for seamless VoLTE to VoWiFi calling.

Why Mobile Network Operators are Interested

The key benefits of WiFi calling for operators:

  1. Combat OTT apps and gain back lost revenue
  2. Provide a better, controlled QoS compared to OTT apps
  3. Provide benefits to subscribers. Happy subscribers = loyal subscribers!

The key benefits of WiFi calling for users:

  1. Simplicity! No need for an app. Just call straight from your phone’s native dialer.
  2. Calling over WiFi doesn’t use up talk time minutes
  3. WiFi calls don’t waste LTE data!
  4. WiFi often has a much higher-quality and a clearer sound

Conclusion

So, while WiFi Offload and WiFi calling are distinct, they both provide benefits to operators willing to shift their network to support calling over WiFi. While offload is designed as a dynamic solution to congestion and limited coverage, WiFi calling provides an opportunity for customers to originate calls over WiFi, not just get offloaded when the cellular network falls short. This gives customers and operators the opportunity to preserve cellular network integrity, and offer higher-quality calls at a lower price. To combat OTT apps and increase customer satisfaction, WiFi Offload and calling present the perfect opportunity to increase revenue and quality of service in a highly competitive market with plateauing or falling profits.

Ryan Gray

Ryan Gray

Partner and Sales Director

Ryan is intrigued by where telecommunications will go in the next few years. As a Partner and Sales Director, she’s been exposed to many aspects of the industry in different technologies and markets. When she’s not speaking in telecom acronyms, you can find her traveling the world, skiing the Colorado Rockies or doing DIY projects on her home.

Subscribe to the Alepo Newsletter