Three Attributes of a World-class 4G-5G Network Migration Capability
By Jon Baldry
Metro Marketing Director
Mobile World Congress 2017 covers many aspects of the telecom industry. Among the hot topics being discussed this year is the continued ramp in excitement around 5G and the impact this will have on all aspects of telecoms networks.
5G promises huge advances in wireless technology, with its greater bandwidth and lower latency that enable a wide array of new services and applications, such as autonomous driving and augmented reality. Radical changes will be required throughout the network, from handset design to the architecture deep into the core of the network. 5G will bring significant challenges to the transport network as well, and also adds a degree of uncertainty as the 5G standards are still under development, so full details on transport network requirements aren’t set yet.
Nonetheless, mobile operators and wholesalers want to be able to evolve seamlessly from today’s 4G-based fronthaul and backhaul environment to a future 5G environment while addressing evolving transport network requirements, including:
- Even higher demands on performance – Low latency, synchronization and higher capacity demands are a given with 5G.
- Ethernet evolution – 5G fronthaul will migrate to Ethernet, creating a hybrid fronthaul/backhaul environment sometimes called crosshaul or Xhaul. But Ethernet needs to adapt to support this new environment first with innovation from the Next Generation Fronthaul Interface (NGFI) initiative and the creation of time-sensitive Ethernet.
- Seamless coexistence of 4G and 5G – Whereas the transitions from 2G to 3G and then 3G to 4G were totally separate networks, 4G doesn’t go away with 5G. 4G infrastructure remains a key element in the new network, which must coexist with the new 5G infrastructure—preferably in a seamless way.
- Virtualization of key network resources – The move to a software-defined network (SDN)- controlled and cloud-structured environment will help facilitate support for Mobile Edge Computing (MEC), fog networking and virtualization of key network resources.

To address these challenges, network operators need solutions that are flexible and open, and offer high performance. To help address these needs, Infinera just introduced a new range of flexponders for its Mobile Fronthaul Solution and additions to its Mobile Backhaul Solution.
These new products are designed to enable mobile operators and wholesalers to evolve seamlessly from today’s 4G-based fronthaul and backhaul environment to a future 5G environment, while also addressing evolving transport network requirements. This is achieved by addressing the three attributes of a world-class 4G-5G network migration capability, namely:
- Flexibility: As mobile networks make the transition to 5G, flexibility will be essential in enabling operators to smoothly evolve their transport networks to support the new environment without the need to “rip and replace” thousands or even tens of thousands of fronthaul and backhaul units located at existing cell sites. Infinera’s new range of mobile fronthaul flexponders provides what we believe is unparalleled flexibility today:
- Deployment flexibility – Configurations are available in three options: a standard plug-in unit for any XTM Series chassis; a hardened Fronthaul Access Unit for non-controlled environments, such as street cabinets; and a fully hardened Remote Fronthaul Unit or “clamshell” for direct mounting to a pole or tower.
- Service flexibility – Infinera’s flexponders are able to support Common Public Radio Interface (CPRI) or Open Base Station Architecture Initiative (OBSAI) protocols and Ethernet over the same wavelengths today, and also have the ability to support the new time-sensitive Ethernet/NGFI framing structure and CPRI over Ethernet mapping via a simple software upgrade in the future.
- Functional flexibility – The flexponder range supports a new “engine” that enables it to operate as a transponder with one-to-one client to line mapping, as well as a muxponder that multiplexes multiple client signals onto a single line or in a hybrid configuration. Ports can be switched from one configuration to another on the fly, and we believe this capability and level of flexibility is unique within the industry.
- Openness: Openness is achieved through SDN control via the Xceed SDN controller and open APIs, as well as though ensuring a radio access network (RAN) vendor-neutral environment capable of supporting any RAN vendor.
- High performance: High performance is achieved through low-latency design and support for superior synchronization, coupled with new patent-pending delay compensation functionality specifically designed to enhance fronthaul deployments in protected networks.
Only Software Upgrades are Required Going from 4G to 5G, Avoiding Rip and Replace of Hardware
5G standardization work will continue this year, and while live 5G is still a way off, it is rapidly approaching. Flexibility, openness and high performance combine to make for a network architecture that enables a smooth evolution to 5G within the mobile transport network. This ultimately provides network operators investment protection and peace of mind through the avoidance of rip and replace as we move to 5G.
For more information, contact us.
Related links:
- Application Note: Enabling Cloud-RAN with Mobile Fronthaul
- Application Note: Evolving Mobile Backhaul to Support LTE-A and 5G