Network | Not the best, will 5G abandon TCP/IP?

TCP/IP is considered suboptimal for more advanced 5G services.

On April 7, the European Telecommunications Standards Institute (ETSI) announced the establishment of a new industry specification working group "Non-IP Networking" (ISG NIN).

The goal of the working group is to research and develop new network protocols for 5G networks to replace TCP/IP.

The press release stated that in 2015, some mobile operators discovered some problems with the TCP/IP-based technology used in 4G networks.

Since the TCP/IP protocol was originally designed for the Internet rather than mobile communication networks, when TCP/IP was introduced into mobile communication networks, it added functions such as mobility, security, and QoS, which made the network more complex and the spectrum usage efficiency lower. In order to solve these problems, subsequent patches and alternative solutions have led to increased costs, delays, and power consumption.

Therefore, TCP/IP is considered suboptimal for more advanced 5G services.

To this end, ETSI established the Industry Specification Working Group for Next Generation Protocols (ISG NGP) in 2015, whose mission is to analyze these problems and propose alternative solutions.

ISG NGP has identified candidate technologies that can directly address these issues, significantly reducing header size, per-packet processing complexity, and latency for real-time media streams, while remaining compatible with the current Internet and new technologies such as SDN, MPLS, etc. In addition, ISG NGP has published a set of KPIs that can objectively evaluate the ability of network protocols to meet operator needs.

Today, following ISG NGP, ETSI has established the ISG NIN working group, which means that the work of replacing TCP/IP has entered a new stage.

Next, the ISG NIN working group’s mission is to better serve new 5G applications and strive to manage new applications at a lower cost and more efficiently.

ETSI said that the work of ISG NIN will first be applied to mobile private networks and then expanded to mobile public networks, covering core networks and radio access networks.

John Grant, chairman of the ISG NIN working group, said that it is crucial to find new Internet protocols that are more suitable for the 5G era, because the current TCP/IP-based networks cannot best support new applications such as industrial control, autonomous driving, and telemedicine.

Kevin Smith, vice chairman of ISG NIN, said that it is undeniable that the IP stack and OSI layered model have promoted global connectivity, but since they originated in the 1970s, they have the limitations of the times. By re-evaluating the basic design principles of network protocols and simplifying network protocols, it can help improve the performance, security and efficiency of access networks and use cases in the 2020s.

TCP/IP restricts the development of mobile networks

In fact, the idea of ​​"next-generation protocol" is not new. Since 2016, the industry has been saying that TCP/IP has restricted the development of mobile networks.

Experts believe that the TCP/IP protocol was invented in the 1970s and was originally designed for fixed networks and network interconnections. Although it has connected countless computers for decades and promoted the booming development of the Internet, it was not born for mobile communication networks.

The terminals connected to the Internet are fixed, and the network architecture is distributed; while the terminals connected to the mobile communication network are mobile, and the architecture is centralized. The two are fundamentally different, and the combination of the two will inevitably lead to problems such as low network efficiency and high costs. Taking the end-to-end user plane protocol stack of the 4G network as an example, the GTP tunnel based on the IP protocol requires layer-by-layer encapsulation, decapsulation, IPSec encryption, ROHC compression, etc., which undoubtedly increases transmission delay and processing costs.

This inefficient combination has resulted in higher costs and has also restricted the performance, security, mobility and scalability of the network. In the future, it will affect the mobile communication network's ability to expand new businesses and vertical markets.

Experts believe that in the future, the 5G era will give rise to various applications such as AR/VR, autonomous driving, and telemedicine, and the TCP/IP protocol will be difficult to adapt to the future, so we need to redefine new protocols.

New IP: Unlocking new opportunities in the future

It is worth mentioning that not only ETSI, but also the International Telecommunication Union (ITU) is discussing this issue.

In 2018, ITU established the Network 2030 Focus Group (ITU-T FG on Network 2030), which aims to explore the development of network technology for 2030 and beyond, and explore new network concepts, new architectures, new protocols, new solutions and new applications. At that time, Richard Li, chairman of the Network 2030 Focus Group and chief scientist of Huawei's 2012 Network Technology Laboratory, introduced the Network 2030 vision in a paper titled "Towards a New Internet in 2030 and Beyond", in which he pointed out:

Mobile network ≈ 3GPP architecture + IP protocol, but facing future needs, the current mobile network has the following problems:

1) At the application layer, the current TCP/IP cannot guarantee throughput and latency

2) There are delay differences at the PDCP layer. Since wireless retransmission is not synchronized with TCP flow control, TCP wastefully retransmits packets.

3) GTP complexity: including tunnel establishment/teardown processing, tunnel header overhead, and additional CP signaling

4) Inefficient use of the protocol:

• "Tunnel" plus "Tunnel"
• Some header fields are repeated
• The overhead is high, sometimes up to 90%

Due to the limitations of latency and rate, the current network cannot guarantee the delivery of new applications in the future, such as VR, holographic, industrial Internet, tactile Internet, etc. "New IP" was proposed to unlock new opportunities in the future.

Not long ago, it was reported that Huawei, China Unicom, China Telecom and the Ministry of Industry and Information Technology jointly proposed a new core network technology standard called "New IP" at the ITU meeting. The Financial Times reported that the proposal supports cutting-edge technologies such as holographic and self-driving cars.