Field insights: Deploying enterprise small cells

With 80% to 90% of mobile usage now occurring indoors, large enterprise small cells provide a flexible, economical way to improve wireless performance for employees. But what are the most important considerations when choosing a solution for this kind of in-building environment?

One important answer emerged at a field trial held in a large financial institution in Mumbai, India: The most effective small cell solutions relied on end-to-end networking expertise and experience. That’s what allowed just 9 small cells, which replaced an existing DAS, to meet or exceed the enterprise’s target KPIs.

By meeting the challenges of a 45,000-square-foot, all-glass office space, this 9-cell solution delivered:

  • A call drop rate of only 0.87% — far better than the targeted <2%
  • An increase in average throughput of 42%
  • A boost in peak throughput of 82%

Here are 5 key field insights shared by experts who were involved in this trial. They explain more specifically how end-to-end network knowledge promotes high-quality performance — at lowest cost — using large enterprise small cells.

1. Femto-to-macro handover expertise

When choosing a small cell solution, it’s easy to focus on femto-to-femto handovers and overlook potential macro cell issues. But considering the all-glass office building construction in Mumbai, it was important for the small cell solution to work seamlessly with the outdoor macro — even if the macro came from a different vendor.

As a result, multivendor macro expertise successfully addressed 2 crucial areas affecting KPI performance:

  • It resolved interference with the macro cell
  • It enabled smooth femto-to-macro handovers

This end-to-end network knowledge contributed to a call drop rate far better than the target KPI, and it highlighted the importance of any small cell vendor being able to provide macro know-how.

2. Backhaul expertise

IP/backhaul expertise was also important, because the financial enterprise’s core network is located in Delhi. Instead of moving this core closer to Mumbai — or creating a new core — the small cell gateway was deployed in Delhi. And the 9 enterprise small cells were all located in Mumbai. Despite this 1,440-km backhaul, all KPIs still met or exceeded the enterprise targets.

3. Upfront planning that reduces cost

The right architecture can deliver outstanding performance with fewer large enterprise small cells. In the Mumbai enterprise, an early solution design called for using 12 cells across the 45,000-square-foot office space. But the initial design was then optimized upfront, based on network expertise and Bell Labs tools, which eliminated 3 small cells.

The 9-cell solution then provided the same coverage — and delivered the same KPIs — as alternative solutions that used more small cells. As a result, the more-efficient solution reduced CAPEX and delivered a better TCO. The solution didn’t require a local, on-premises gateway either, helping to further reduce CAPEX.

Small cell placement

Small cell placement - Small cells shown in red. Cell number 2 was eliminated after design optimization.

Costs can be reduced even more when the same small cell products are used across small, medium, and large deployments. That’s because identical skills and expertise can be applied within any type of enterprise. And that simplifies the tasks of operations and support staff — for example, when working with software and configurations.

4. Small cell scalability

In a busy large enterprise, the wireless network must be able to add or reduce capacity and coverage rapidly. That means large enterprise small cell solutions need to scale easily from single-digit to double-digit deployments — while delivering the same quality of performance.

For that reason, the end-to-end small cell network architecture must provide this small cell scalability. The architecture used in the Mumbai enterprise, for example, is regularly used across both small and large enterprises.

But alternative solutions in the trial presented a business case that works only for deployments of 8 or more small cells. These types of solutions also have a limit on the maximum number of nodes they can support. Hence they’re less flexible in addressing small cell scalability.

5. Small cell architecture reliability

The most reliable enterprise small cell solutions avoid single points of failure. For example, each of the 9 cells used in the Mumbai financial institution operates independently. That makes sure that any failure is isolated and does not affect the rest of the network.

But not all small cell architectures work this way. Premises-located gateways and controllers enable single points of failure to bring down the in-building network.

Do these insights really make a difference?

In our experience — backed by the results in Mumbai — they do. The 9-cell solution used in Mumbai was developed using Alcatel-Lucent end-to-end network expertise and methods, along with Bell Labs tools that simplify and optimize in-building deployment. Alcatel-Lucent solutions can also take advantage of a large enterprise’s existing IT infrastructure to help maintain high availability.


Small cell solutions web page
Bell Labs Consulting web page
In-Building Solutions page
In-Building/Venue Expertise Matters video

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