5G is the latest generation of cellular network standards. There’s a tremendous amount of activity around it in the industry. But how does 5G relate to Internet technology? Are there 5G-related work items that the IETF should be working on, for instance?

While at times the 5G stories take on an almost myth-like nature, the basics underpinning 5G relate to concrete changes in the technology and our increasing needs for communication. The traffic growth for both our smartphones and homes continues to be exponential. And as organisations and societies increasingly connect their systems, there are also many new needs.

5G responds to these needs with new radio technology and a core network that employs state-of-the-art network technologies such as an increased use of cloud, virtualisation, and open source components and processes. From a standards perspective, the timelines for the first systems are very near. The 5G work happens to a large extent in 3GPP, as did previous generations. The work on 5G is planned to take place in two releases. The first one, Release 15, is scheduled to be completed by September 2018. Additional work will be done in Release 16, which will be completed by March 2020.

What is 5G?

5G is basically a new, very capable radio. With beamforming, MIMO antenna technology, and frequency bands reaching to millimetre waves, it provides both higher transmission speeds and serves more users at the same time — 5G radio can provide speeds in the Gigabit range, up to 10 Gbps or even beyond (for larger numbers of users the speeds will be lower, but still at least tens of megabits per second, for tens of thousands of users).

The new radio is also needed to serve mass deployment of networked sensors and to enable various mission-critical services that may require better latency or reliability characteristics.

Mobile broadband is likely to be the most popular use case for 5G but other industries will be able to take advantage of the new communication and cellular capabilities it will provide. The ultimate goal is to be able to tailor communication platforms for a wide range of different services, ranging from low-powered IoT devices to self-driving cars, from mission critical public safety communication to providing services to energy providers. There is also a higher demand on flexibility and configurability/orchestration.

5G and IP

From an IP networking perspective, 5G follows the same evolution as the rest of the networking industry. However, from a practical perspective, this is a big change, and requires effort. The work on details is ongoing for Release 15, but architecturally, the key directions are clear.

Interfaces to devices are relatively similar to those in 4G; however, one major difference is the ability to place different devices in different virtual networks, or “slices”, that can evolve independently from each other, both in resources and networking technology.

Another difference to 4G is that the 3GPP security group plans to enable a more flexible authentication framework for the devices. And some of the control protocols inside the network may be changed from DIAMETER-based ones to REST-based APIs.

From what we understand, the tunnelling-based architecture for mobility is not changing, but, of course, with most services being provided in virtual environments, the tunnel endpoints may physically reside in different places.

It should also be said that 5G is not a replacement for Internet-based services or Internet technology: the majority of traffic that 5G will carry is for usual Internet services. 5G is also not immune to impacts from Internet evolution — for example, we’ve seen big changes in the use of encryption in the Internet, transport protocols are evolving, the use of CDN systems is growing, and all networks are becoming virtualised, software-defined, and cloud-resident systems. 5G networks need to serve the Internet that continues to evolve in this manner.

Is there an IETF connection?

It is useful to understand how 5G affects Internet technology. The IETF’s work has been and will be affected by 5G. To begin with, the IETF works on many of the general facilities that modern networked systems such as 5G are based on.

Conceptually, one can think of the interactions as falling in the following categories:

• New dependencies on existing IETF technology. For example, the flexible authentication framework mentioned above is EAP (RFC 3748, RFC 5448). This is likely to be merely a reference or (if required) small additions to existing RFCs.

• Dependencies to ongoing work at the IETF. This includes various general facilities as noted above, but also other things. For example, the IETF DETNET working group defines mechanisms to guarantee deterministic delays for some flows across a network. As one of the 5G use cases is time-critical communication and low-latency applications, this is a component technology that is being looked at. Similarly, IETF routing-related work such as traffic engineering, service chaining and source routing can likely manage traffic flows in 5G networks.

• Topics where there is a clear demand for a feature, but it is unclear whether changes to Internet technologies are needed, or the details remain to be determined. For example, in the upcoming IETF meeting in Prague, we will be discussing whether additional support is needed for “Network Slicing”. There are many IETF tools, however, for dealing with virtualisation and separation of networks, so the first order of business is probably mapping what can be done with these.

• Larger, architectural changes. For example, “future Internet” type solutions such as ICN (Information Centric Networking) are sometimes suggested also in the context of 5G. While these are perhaps unlikely in the first release of 5G, it is, of course, certain that the Internet will continue to evolve (and there will be future releases of 5G standards as well).

Going Forward

We asked Gonzalo Camarillo and Georg Mayer (liaisons between 3GPP and IETF) about collaboration between IETF and 3GPP. They said that our best approach is to ensure that the 3GPP engineers are involved in the IETF work they are interested in, and that 3GPP states clearly what their requirements  (rather than solutions) are. They also noted that the work in 3GPP is ongoing, hence completing protocol requirements for 5G will still take some time. Gonzalo and Georg will be contacting the relevant parties on both sides to keep us in sync.

Exchange of information would also benefit from informal collaboration, for instance through Internet technology experts working with the 3GPP community. This enables common topics to be easily discussed and brought forward.

We should also note that there are clear boundaries between the two organisations. The IETF works on Internet technologies which may or may not get used in different networks. 3GPP puts together systems, architectures, and designs protocols specific to their networks and layers. The IETF is not in charge of making system level or requirement decisions for the 3GPP. Similarly, 3GPP leaves the evolution of Internet protocols to the IETF.

Also, Alissa Cooper, Chair of the IETF, recently reported on her visit to a 3GPP meeting.

Finally, it should be noted that many of the existing tussles on the Internet continue to exist with 5G. For example, the ability to provide a highly dynamic and programmable radio environment continues to present opportunities for collaboration between networks and applications.

However, such collaboration is not something that has historically been easy on the Internet. When we discussed this as a part of the growing use of encryption, the necessary changes to network management practices due to the encryption changes caused pain for operators. Perhaps as some time passes, and networks continue to evolve, we could consider network–application collaboration as an opportunity and ask what useful things networks can do for applications?

Co-authored by Jeff Tantsura

The original post appeared on IETF Blog.

Jari Arkko is an expert on Internet Architecture with Ericsson Research in Jorvas, Finland and former Chair of the IETF.

Jeff Tantsura has been in the networking space for 20+ years and has authored/contributed to many RFCs and patents. He is the chair of the IETF Routing Working Group, is a consulting VP Network Architecture with Futurewei, and a Member of the Advisory Board at Volta Networks.

Image credits: Ericsson, 3GPP