Introduction of mid and high-band spectrum results in RAN densification, as providers deploy more Distributed RAN (DRAN) sites and introduce fronthaul networks to support new RAN architectures like Centralized RAN (CRAN). Distribution of storage/compute resources to the edges of the network, and placement of network functions at the mobile edge will also impact transport network requirements. These new architectures, combined with network slicing, promise to deliver end-to-end SLAs optimized to a specific traffic profile across RAN, transport network and mobile core.
As such, the 5G network is much more distributed and dynamic, which is more complex and requires near real-time management. This puts pressure on mobile service providers to look for new ways of deploying and managing 5G networks and services. Providers need more automation in the operation, administration and maintenance of their networks to achieve the performance and cost savings they require, and to receive the full benefit from the 5G technology.
We know from previous blogs that 5G is a game changer. The 5G transport network will have to evolve in terms of capacity, latency and security. In addition, due to densification and virtualization, 5G transport networks must also be automated and optimized in near real-time to ensure low cost of operations, avoid overbuild and unnecessary capex, and enable flexibility when rolling out new services for subscribers. This automation requires three key capabilities to ensure the 5G IP transport network is resilient, automated and scalable:
- standard based service capabilities towards diverse applications on North Bound Interface (NBI)
- routing control plane consolidation: to minimize routing protocols in the IP transport network
- automated e2e dynamic service provisioning and slicing using software-defined network (SDN) for the IP transport network
Ericsson’s approach to 5G transport is to use these fundamental capabilities as the building blocks of our IP portfolio.
Standard Based Automated Network : For 5G services to scale, automation is important for IP networks. Automation requires 5G transport to support standard APIs and support North Bound Interface (NBI). For example, support for NetConf and YANG models to enable automated configuration. With these capabilities, the routing infrastructure can be integrated into end-to-end orchestration and assurance systems providing the following benefits to service providers:
- automatic configuration of routers
- reduced complexity in design, build and operation
- reduced operational expense due to automation
- end-to-end flexible and programmable network
Segment Routing (SR) : As the transport network grows more complex and denser, there is a need to simplify and consolidate the multiple numbers of protocols required to enable an MPLS network. Segment routing makes it possible to configure a network that efficiently routes packets along a Label-Switched Path (LSP) and enables network automation/programmability. Segment routing brings the following advantages to the providers:
- Reduction in the protocol stack: LSP can be triggered without signaling protocols such as Resource Reservation Protocol (RSVP) or Label Distribution Protocol (LDP). This reduces complexity and results in a more scalable network.
- SDN integration and network automation: Ericsson Router 6000 supports segment routing and PCEP integration using the standard protocols like BGP-LS.
- High availability: Rapid failure recovery is possible in less than 50 milliseconds using Topology-Independent Loop-Free Alternate (TI-LFA).
- Automated Network Slicing : One of the key offering and architecture requirements of 5G is network slicing. Slicing enables new services and reduces costs by creating network slices specific to certain applications and/or traffic types designed and built for a given SLA. The IP transport network is a key enabler and component for end-to-end network slicing.
When creating and lifecycle managing network slices, all the domains, RAN, packet core and transport, are automatically managed via the orchestrator. This creates a dynamically controlled and orchestrated transport network that requires minimum manual interaction. In other words, network slices can be created using the underlay and overlay network. The underlay network handles the infrastructure connectivity and the network overlay handles the services running on top of the underlay.
Ericsson has considered all the above in developing our mobile transport portfolio and ensuring seamless integration into our automation and orchestration solutions. Ericsson transport solutions bring Service configuration capabilities integrated with ENM for transport modernization and E2E transport orchestration. Ericsson Orchestration solution and Router 6000 are based on standard NETCONF, and have ECIM/YANG models ensuring reduction in network complexity, higher operational efficiencies and ease of troubleshooting. These capabilities will help service providers build a scalable 5G IP transport supporting simplified, open and automated SDN orchestration-enabled network.