According to Spirent’s vice president of wireless, Nigel Wright, the effort to create a world without wires actually increases the bandwidth requirements of wired networks. Mobile backhaul already accounts for a large portion of operator’s overall operating costs, which drives backhaul migration from dedicated TDM to packet-based Ethernet, a much more cost-effective technology that can significantly lower cost of bandwidth per subscriber. However, Ethernet in the backhaul brings challenges which, if not addressed during network architecture design and later during live operations, can cut into the potential cost saving or new revenue opportunities it presents.
“The target is a converged mobile backhaul that delivers quality of experience on an Any-G network,” Wright said. “Mobile operators face the challenge of achieving TDM-like efficiency from IP/Ethernet transport. Avoiding any hidden surprises comes down to testing, both in equipment vendors’ labs as well as service provider networks, and knowing what to test and how to test it.”
Key areas that are challenging in the mobile backhaul and require specific testing focus are:
* Mobile handoff. Can Ethernet timing (IEEE 1588v2 PTP) deliver TDM-like synchronization for voice traffic to avoid dropped calls?
* Application quality. Can differentiated Class of Service (CoS) deliver TDM-like guaranteed bandwidth for multiplay traffic to avoid issues such as degraded video?
* Failover. Can MPLS-TP deliver TDM-like alarms, performance monitoring and failover to avoid dropped calls or data sessions?
* Turn-up. Are operators prepared to provision tens of thousands of new backhaul circuits this year with existing resources?
* Troubleshooting. Can operators scale to meet demand while addressing current customer issues, monitor service performance on the backhaul and quickly locate problems without additional dispatches?
* Out-of-franchise vendor management. How operators validate third-party providers’ delivery on SLAs? Or validate that their network offers customers said SLA performance levels?
“These issues can delay deployment by affecting the choice of technologies during design and can put a service provider behind the competition for years,” said Michael Howard, co-founder and principal analyst, Carrier and Data Center Networks, Infonetics Research. “Solutions such as those from Spirent help providers clarify their design issues and accelerate their deployments.”