Mobile network operators across the globe are currently in the process of upgrading their networks to support the new functionality, performance targets, and higher capacity levels required to support the rollout of 5G. These operators are now in the initial stages of the next phase of 5G deployments with the move to the dedicated 5G standalone (SA) core, which enables operators to start to plan new services that leverage the full capabilities of 5G, such as ultra-reliable low-latency communications (uRLLC) services. The rollout of full SA-based 5G drives the need for network operators to rearchitect their networks to support:
- Significantly higher capacity requirements that the full range of SA-enabled 5G services will drive into the network
- More dynamic bandwidth patterns with capacity reallocation as services become more time-of-day dependent
- Advanced RAN techniques such as massive multiple-input multiple-output (MIMO) driving the requirement for the xHaul architecture with a fronthaul domain
- An increase in the number of RU devices that are supported over a common xHaul access network driven by cell site densification of both additional macro cells and small cells
- The addition of new network capabilities such as multi-access edge compute
- Meeting higher performance requirements in terms of low latency and synchronization and timing distribution
To meet these challenges, network operators are reevaluating their optical network architectures and considering the best approaches to meet their specific needs. One of the approaches being considered by many network operators is a future architecture built around point-to-multipoint XR optics.
In addition to supporting point-to-point, XR optics is ideally suited to the point-to-multipoint traffic patterns created by 5G xHaul networks. In fact, we often use the analogy of the mobile radio network with a single central “high capacity” antenna communicating with multiple “lower capacity” handsets when explaining the concept of point-to-multipoint optics, as shown below.
Of course, new technological approaches to any challenge can be interesting from an engineering point of view, but they need to bring tangible benefits to the network operator and ideally the end customers too. Here are the 6 reasons why 5G and XR optics are a perfect match :
Improve Economics
First and foremost is the significant impact that the technology brings to the economics of 5G transport networks. Overall, XR optics has been shown in network operator modeling to potentially bring CapEx savings of up to 70+%*. Specific modeling for new 5G fronthaul and midhaul xHaul domains has been shown to bring CapEx savings of over 45% and space and power OpEx savings of over 70%. Not only does this help the business-case economics for 5G transport, but the lower cost base also potentially opens the opportunity for new xHaul services and use cases that were previously not economically viable.
Free-up Scarce Space and Power Resources
In addition to the capital expenditure advantages for reduced networking hardware created by XR optics, there is a substantial operational expenditure advantage through reduced space and power requirements within the network. A key additional advantage in 5G xHaul networks is that they are typically already space and power constrained at a time when new requirements such as MEC and the DU and CU within xHaul locations are further compounding the problem. An XR optics-based network frees up this critical space and power, which can then be used for key 5G transition requirements such as MEC and DU/CU processing.
Support New Point-to-Multipoint Architectures
XR optics enables network operators to migrate to a point-to-multipoint transport infrastructure that more closely matches the traffic demands in all xHaul domains. Naturally, this is a key enabler to the economic advantages outlined above, but it also brings benefits in terms of network planning and the ability to support asymmetrical optical services to match the actual traffic flows, which are typically also asymmetrical in a mobile network.
Leverage Existing PON Optical Infrastructure
As discussed in this earlier blog, mobile transport networks often need to support single fiber working infrastructure at the edge of the optical networking domain, commonly in PON access networks. XR optics provides network operators with the tools they need to bring high-capacity services that require coherent optics to this infrastructure via a high-capacity coherent DWDM overlay network and also creates the possibility to support asymmetrical traffic flows.
Support Multi-generational Upgrades
A generic advantage of all XR optics networks is the ability to support multi-generational network upgrades, where the upgrades are only required at nodes that need more capacity rather than at all locations in the network. This is a particular advantage in 5G transport networks as the impact of unnecessary upgrades could be considerable with optics mounted in RU devices located on cell towers, which can be very costly to upgrade.
Automate Capacity Allocation
With XR optics, network operators can automate initial capacity turn-up and capacity expansion via advanced automation and software-configurable bandwidth. Again, with RU optics mounted up a cell tower, the ability to provision additional capacity remotely via software is a particular advantage in 5G transport networks.
Conclusions
XR optics, and Infinera’s ICE-XR portfolio, can offer significant benefits to network operators planning high-capacity xHaul networks to support 5G. The industry is on the cusp of evolving 5G services from initial high-speed broadband services to a broader range of new advanced services based on the new capabilities that 5G brings. This will involve considerable reengineering of the complete mobile network, including the underlying transport network, and XR optics has the potential to positively impact this migration now and as 5G continues to evolve. If this sounds interesting, then click here to read more in our recently published XR optics in 5G xHaul Transport Networks application note.
*BT paper presented at ECOC 2020 – “CAPEX Savings Enabled by Point-to-Multipoint Coherent Pluggable Optics Using Digital Subcarrier Multiplexing in Metro Aggregation Networks”