Ladies and gentlemen, thank you for standing by and welcome to ADTRAN's First Quarter 2020 Earnings Release Conference Call. During the course of the conference call, ADTRAN representatives expect to make forward-looking statements, which reflect management's best judgment based on factors currently known. However, these statements involve risks and uncertainties, including the continued spread and extent of the impact of the COVID-19 global pandemic. The successful development and market acceptance of our products, competition in the market for such products, the products and channel mix, component cost, manufacturing efficiencies and other risks detailed in our Annual Report on Form 10-K for the year ended December 31, 2019. These risks and uncertainties could cause actual results to differ materially from those in the forward-looking statements which may be made during this call. It is now my pleasure to turn the call over to Tom Stanton, Chief Executive Officer of ADTRAN. Sir, please go ahead.

Thank you, James. Good morning, everyone. We appreciate you joining us for our first quarter 2020 conference call. With me today is ADTRAN's CFO, Mike Foliano. Following my opening remarks, Mike will review the quarterly financial performance in detail, and then we'll take your questions. Before getting into the results, I'd like to say a few things about the unprecedented times associated with the COVID-19 virus. First, from the entire ADTRAN family, we want to send our sympathy and best wishes to all of those affected and impacted by the virus. Our hearts go out to you. Given the current reality, I cannot begin to tell you how proud I am of the ADTRAN team and how they have rallied to continue to provide critical products and support to address the needs of our customers and consumers. With the safety of our employees, customers and communities in mind, we were proactive in our business continuity planning. This included successfully moving the majority of our employees to a work-at-home environment, implementing on-site employee safety measures and advanced procurement of components to ensure supply for our customers that are delivering critical broadband services to consumers. We have also been very active in supporting communities, trying to deliver emergency broadband connectivity to support education and other critical services. At no time in history has the need to connect people over broadband been more important, and our team has done a fantastic job stepping up to help our customers in these extraordinary times. Thus far, 2020 is proving to be a transformative year for us as the long-term investments we have made in fiber access solutions are starting to pay off. We are having success in the regional service and emerging service provider segments, which include rural operators, municipal operators, utilities and electric co-op broadband providers in the U.S., as well as with alternative network providers in the U.K. and Europe. I'm also pleased to let you know that we had several major awards from Tier 1 service providers in the U.S. and Europe this quarter. We have continued to invest in our widely deployed Total Access 5000 platform to provide industry-leading capacity, features, and capabilities for GPON and XGS-PON services. In addition, ADTRAN has led the industry with the development of an open disaggregated software-defined fiber access solution centered around our SDX product family and our Mosaic Cloud Platform. Both of these platforms put the company in a strong position to provide the best solutions to enable broadband service providers of all sizes, topologies, and geographies to deliver more services faster, while significantly lowering their cost. We were pleased with the revenue contribution and sustained fiber access momentum from our domestic regional service provider and emerging service provider market sector, which reported a revenue increase of 73% on a year-over-year basis. Additionally, we have seen an increased focus from governments spurring investment in broadband infrastructure and expect, given the lessons recently learned, this focus will intensify. The U.S. recently implemented the $2 trillion CARES Act, which includes incremental funding for the USDA ReConnect Program and is preparing to distribute the first phase of the $20.4 billion FCC Rural Digital Opportunity Fund in 2021. ADTRAN has also been highly active in driving and influencing these investments. We believe that our solutions are exceptionally well positioned to enable operators to secure funding and help them plan, engineer and deploy gigabit services to enable communities of all sizes to be connected. The drive for fiber deployment and Gig Plus services continues to build additional momentum in Europe and other parts of the world. I am also excited to share the progress we're making with Tier 1 operators in the U.S. and Europe. We have recently won 3 major long-term awards with Tier 1 operators, with all 3 selecting the SDX portfolio and Mosaic Cloud Platform. Last week, we announced that Deutsche Telekom has selected ADTRAN's SDX OLT solutions for deployment as part of its Access 4.0 network. It will also be deployed in its existing fiber-to-the-home architectures along with Mosaic Cloud Platform. As mentioned in the announcement, the goal of DT's Access 4.0 program is to create an open, programmable and scalable fiber access architecture to cost-effectively and rapidly deliver gigabit services to meet the increasing demand of DT's residential, wholesale, and business customers. Further, during the quarter, we received an additional SDX OLT and Mosaic Cloud Platform award from a Tier 1 operator here in the U.S. That product is currently in the lab and is expected to start deployment in the first half of next year. Once operationalized, the operator's intent is to use the SDX and Mosaic to deliver SDX services across their entire footprint. Finally, we recently signed a contract with another large Tier 1 European operator for the SDX and Mosaic Cloud Platform after being selected in their competitive RFP process. This is a brand new customer to ADTRAN, and our current expectation is for shipments to begin in the first half of next year. In addition to these awards, we also announced last week a strategic joint development agreement with Orange, one of the world's leading telecommunication operators as part of its access renewal and evolution strategy. Winning these transformative long Tier 1 awards will have a significant impact on our company in the future. They solidify our market position and validate our vision of virtual open network architecture of the future. Given that backdrop, the first quarter came largely as anticipated with strong demand overall and robust performance in our domestic, regional, and emerging service provider market segments. From a top-line perspective, revenue for the quarter was $114.5 million with 45.1% gross margins. Network Solutions accounted for 85% of the revenue and $97.4 million. Global Services revenue contributed $17.2 million. Our fiber business grew 13% over the previous quarter and increased 26% on a year-over-year basis as PON fiber access and fiber CPE solutions continue to be our top sales growth categories as we gain market traction. We continue to see strong demand for fiber broadband and fiber extension opportunities in the regions we serve. We maintain our belief that we are at the beginning of a significant investment cycle for fiber deployment, driven by technology advancements, regulatory influence, and vendor disruption. In addition to our domestic emerging provider momentum, we are continuing to win new fiber access projects with alt-net providers in the U.K. and the rest of Europe. We are also progressing new opportunities in emerging international markets as well. From an organizational perspective, we'll continue to implement structural changes to improve our operational costs, achieving a 15% year-over-year decrease in OpEx, strengthening gross margins, and providing greater flexibility to focus and deliver more in our key growth areas. In the face of this global pandemic and other market challenges, I am happy with the way the team has responded and performed. We implemented our COVID-19 response team and our business continuity plan well ahead of the CDC guidance from government actions. This enabled us to be proactive, protecting our employees, customers, and communities and ensured that our supply chain, production, and support was elevated to provide outstanding service to our customers and communities that they serve. We do have concerns as there is still material near-term uncertainty due to the pandemic. Fortunately, we believe we are in a good position to weather the changing environment for a number of reasons. First, ADTRAN has a strong balance sheet with the available liquidity to weather even the most extreme stress test. Our service provider customers are among the most resilient in this pandemic, given their focus on building and supporting critical infrastructure. Short-term demand for residential broadband remains strong and the future is bright as this pandemic has highlighted the positive gaps between fixed broadband access and wireless networks. I'm encouraged by our recent wins and how this positions us from other operators seeking to find their next generation platform. I am also encouraged by the growing number of emerging municipalities and utility broadband service providers that are selecting ADTRAN to help them transform their communities. Mike will now provide an overview of the financials, and following his remarks, we'll open the call up for any questions you may have.

Thank you, Tom, and good morning to everyone. I will review our first quarter results and provide our view of the second quarter of 2020. During my report, I will be referencing both GAAP and non-GAAP results. With respect to non-GAAP financial measures that are discussed on this call, but are not presented in our earnings release, reconciliations to their comparable GAAP measures are published in a supplemental financial schedule that appears on our Investor Relations webpage at www.adtran.com. For non-GAAP measures discussed on this call that are presented in the earnings release, reconciliations are contained in the release. The supplemental financial schedules on our webpage also present certain revenue information by segment and category and other non-GAAP reconciliations, which I will be discussing today. As Tom stated, ADTRAN's first quarter revenue came in at $114.5 million compared to $115.8 million in the prior quarter, and $143.8 million for the first quarter of 2019. Breaking this down across our operating segments, our Network Solutions revenue for the first quarter was $97.4 million versus $96.2 million reported for Q4 of 2019, and $125.8 million in Q1 of 2019. Our Services & Support revenue in Q1 of this year was $17.2 million, compared to $19.6 million reported for the fourth quarter of 2019, and $18 million in the first quarter of 2019. Across our revenue categories, Access & Aggregation revenue for quarter 1 of 2020 was $66 million compared to $74.6 million in the prior quarter, and $99.8 million in quarter 1 of 2019. Revenue for our Subscriber Solutions & Experience category was $42.2 million for the quarter versus $33.2 million for quarter 4 of 2019 and $36.8 million for quarter 1 of 2019. Traditional & Other Products revenue for the quarter was $6.4 million compared to $8 million for quarter 4 of 2019 and $7.3 million for quarter 1 of 2019. Looking at our revenues geographically, domestic revenue for Q1 2020 was $79 million versus $69.9 million reported in quarter 4 of 2019, and $72.5 million in quarter 1 of 2019. Our international revenue for quarter 1 of 2020 was $35.5 million compared to $45.9 million for quarter 4 of 2019, and $71.3 million in quarter 1 of 2019. For the first quarter, we had 3 customers that accounted for 10% of revenue, 2 of which were domestic and 1 international. Our GAAP gross margin for the first quarter of this year was 45.1% as compared to 40.8% last quarter and 42.2% in the first quarter of 2019. Non-GAAP gross margin for quarter 1 was 45.4% as compared to 41.2% in the prior quarter, and 43% in the first quarter of 2019. The quarter-over-quarter and year-over-year increases in both GAAP and non-GAAP gross margins were driven by our product and geographical mix, as well as our operational efficiencies and restructuring savings, partially offset by an increase in freight-related expenses. Total operating expenses on a GAAP basis were $56.5 million for quarter 1 of 2020, compared to $61.3 million reported in the prior quarter, and $66.8 million for quarter 1 of 2019. Both the quarter-over-quarter and year-over-year decreases in operating expenses were a result of market-driven decreases in our deferred compensation expenses, lower salary, and restructuring-related expenses in both SG&A and R&D, partially offset in the quarter by increases in our IT expenses. On a non-GAAP basis, our first-quarter operating expenses were $56.7 million compared to $56.8 million in the prior quarter and $60.5 million in quarter 1 of 2019. The non-GAAP quarter-over-quarter decrease in operating expenses was primarily the result of broad expense controls and salary-related expense reductions as a result of our restructuring program initiated in 2019. These reductions were offset by higher variable fringe benefit expenses and an increase in our IT-related contracts services. The non-GAAP year-over-year expense decrease was primarily attributable to reductions in salary expenses, partially offset by an increase in contract services. Our operating loss on a GAAP basis for the first quarter of 2020 was $4.9 million compared to an operating loss of $14.1 million in the prior quarter and an operating loss of $6.2 million reported in Q1 of 2019. Non-GAAP operating loss for quarter 1 of 2020 was $4.6 million compared to a loss of $9 million in Q4 of 2019, and an operating income of $1.4 million in quarter 1 of 2019. Both the GAAP and non-GAAP quarter-over-quarter and year-over-year improvements were attributable to higher gross margins due to product and services mix on lower sales volumes and operating expense reductions. Other income on a GAAP basis for the first quarter of 2020 was a loss of $9.4 million compared to income of $3.2 million in the prior quarter and $7.2 million of income in quarter 1 of 2019. Our non-GAAP other income for the quarter that just ended was a loss of $7.5 million compared to income of $2.9 million in Q4 of 2019, and an income of $5.3 million for quarter 1 of 2019. The decreases this quarter in both GAAP and non-GAAP other income, as compared to both quarter-over-quarter and year-over-year were primarily market-driven losses in our investment portfolio. The company's tax provision for the first quarter of 2020 was a benefit of $4.4 million as compared to an expense of $800,000 in the prior quarter and an expense of $300,000 in the first quarter of 2019. The current quarter tax benefit was primarily related to the passage of the CARES Act in the U.S., partially offset with tax expense in our foreign operations as the deferred tax benefits generated in the current quarter by our domestic operations were offset by additional changes in the valuation allowance previously established during the third quarter of 2019. GAAP net income for quarter 1 of 2020 was a loss of $10 million compared to a loss of $11.6 million in the prior quarter and a net income of $800,000 for the first quarter of 2019. Non-GAAP earnings for the first quarter of 2020 was a loss of $2.2 million as compared to a loss of $2.5 million in the prior quarter and a net income of $4.9 million in quarter 1 of 2019. Earnings per share, assuming dilution on a GAAP basis was a loss of $0.21 per share as compared to a loss of $0.24 per share last quarter and earnings of $0.02 per share in the first quarter of 2019. Non-GAAP loss per share, assuming dilution in the first quarter of 2020 was $0.05, consistent with the prior quarter and comparing to earnings of $0.10 per share in quarter 1 of 2019. Turning to the balance sheet. Unrestricted cash and marketable securities totaled $136.6 million at quarter end, after repaying our taxable revenues bond, debt of $24.6 million in January and paying $4.3 million in dividends during the quarter. For the quarter, we used $24,000 of cash for operations. Net trade accounts receivable was $86.5 million at quarter end, resulting in a DSO of 69 days, compared to 72 days in the prior quarter, and 62 days at the end of the first quarter of 2019. The variability in DSOs quarter-over-quarter and year-over-year is mainly attributable to the timing of shipments during the quarter and customer mix. Net inventories were $99.5 million at the end of the first quarter, compared to $98.3 million in Q4 of 2019 and $93.6 million at the end of Q1 2019. We believe that we are positioned to maintain adequate liquidity in the current environment. Looking ahead to the next quarter, considering the possible effects of the ongoing COVID-19 pandemic, the book and ship nature of our business, the timing of revenue associated with large projects, the variability of order patterns and the customer base into which we sell, as well as fluctuations in currency exchange rates in our international markets may cause material differences between our expectations and the actual results. We expect that our second quarter 2020 revenue will be in the range of $123 million to $133 million. After considering the projected sales mix, we expect that our second quarter gross margin on a non-GAAP basis will be about 41%. We also expect non-GAAP operating expenses for the second quarter of 2020 to be in the range of $53 million to $54 million. Finally, we anticipate the consolidated tax rate for the second quarter of 2020 on a non-GAAP basis will be in the high 20s percentage rate. We believe the significant factors impacting revenue and earnings realized in 2020 will be the following: the macro spending environment for carriers and enterprises, the ongoing effects of the COVID-19 pandemic, the variability of mix and revenue associated with project rollouts, the proportion of international revenue relative to our total revenue, professional services activity levels, both domestically and internationally, the adoption rate of our broadband access platforms, potential changes in tax laws, currency exchange rate movements, and inventory fluctuations in our distribution channels. Once again, additional financial information is available at ADTRAN's Investor Relations webpage at www.adtran.com. Now I'll turn the call back over to Tom.

Thank you, Mike. James, at this point, we'll open it up for any questions that people may have.

[Operator Instructions]. And our first question comes from the line of Rod Hall with Goldman Sachs.

This is Ashwin on behalf of Rod. Tom, I want to talk about the U.S. trend. Nice growth in Q1 here. I was hoping you could quantify -- give us some color on what you're seeing in terms of broadband demand and the activity here in the U.S. and if you could handicap that across the Tier 1 and Tier 2 and 3 that would be really helpful and how you're thinking about the sustainability of that momentum into Q2?

Yes. You are right, demand in the U.S. was strong. I would say we probably saw a bigger pickup in the rural carriers, the smaller carriers than in the larger carriers. Although, we did see pretty good demand in the larger as well, just from an order flow perspective. But it was definitely the Tier 3 carriers and utilities that were actually stronger.

And -- sorry guys.

Go ahead. No, go ahead. I know I didn't answer your thought on the momentum. I would say that we had a very good order flow in Q1. I mean, we've just given your guidance. Our guidance is impacted by a couple of things. One, we're typically a booking ship business, that's still the case. So, we don't know what the second half of the quarter will be in relation to the first half of the quarter from an order flow perspective. Number two, we're a little -- the supply chain, although, it is -- we've been able to manage any really critical or difficult situations with our customers in making sure that they get the products that they need. We still do not have a clean supply chain at this point in time.

Got it. My next question is on Europe, obviously one of your large European customers paused in the second half last year. Just wondering if -- what's going on there or any color you can give there.

Yes, sure. They came back like we expected. They're kind of more in line with what they have with a traditional Q1. I didn't see a bounce back, but we did see it come back to kind of more normalized Q1 spending, so definitely stronger than Q3 and Q4 -- materially stronger than Q3 and Q4.

And our next question comes from the line of Richard Valera with Needham & Company.

Just wanted to follow up on -- a question on that large European customer. So you announced it's an OLT win with them as well. And just wondering how we should think about that relative to the historical base of business you had with them, that's been focused on vectoring and super vectoring. Do you think this is additive to that or ultimately largely substituted as they shift CapEx from perhaps vectoring more towards fiber?

Well, I think they have a plan. First, so we did talk about 2 European carriers one, which we actually named because we were -- they were kind enough to move forward with release on our press release, which was Deutsche Telekom. What typically happens is you'll see an overlap of both technologies get played, and then you'll see a kind of movement towards the newer technology over time, and that will ultimately be the primary source of the revenue. So I wouldn't expect any different here.

That makes good sense. And then I -- just quick questions on your other 2 Tier 1s. Looks like one European and one domestic. Just wondering if you can give us any sense of the potential of those programs longer term, and how much to your knowledge are they success-based. Obviously, you've had some wins in the past where you've gotten the win, you've gotten qualified, and ultimately haven't had significant deployment, because it was ultimately a success-based product and it wasn't just a lot of sales. So just wondering if you can give us a sense of are these similar, or are these more plans that will be deployed largely across the network, somewhat independent of specific near-term sales objectives?

Well, let me start with the U.S. carrier, those tend to be more success based. So, although, there is a plan to roll this out across the entire footprint, and because of the capabilities of the platform, the intention would be to actually roll this out. Although, it's XGS-PON, the capabilities of the platform allow you to use it at PON speed or XGS speeds, and I think that they'll leverage those capabilities. And the intention is, hopefully, their intention is what they've stated is that this will become the platform that they move forward to on a going forward basis. But knowing the U.S. market, they are very much -- they look for areas that the ROI meets specific requirements, and I think it will be largely success based. Although, they'll probably be prebuilds and competitive things that weigh into that. The large carrier in Europe is very much a programmed initiative, very similar to what we've seen in other places in Europe. There's a strong government push in that country to deploy fiber, it's very public. And they have a very structured plan for deployment. So, although, I can't tell you, none of it would be success based that there is a plan to deploy fiber, which is similar to other places in Europe and they seem to be marching ahead. So I would say that those 2 are different.

And, historically, you've been -- I know you don't give guidance more than one quarter out. But you have historically been willing to give typically some color in out quarters beyond the next quarter. Just wondering if there's anything you could say about how you're thinking about the back half, maybe relative to historical seasonality, if there's anything we should be aware of in the back half that might be sort of better or worse than what we've seen historically?

Well, this is probably -- this is not news to anybody on this call. The most difficult time to try to reach out and look farther. So, you know, the worry that -- the positive thing is everybody gets back to work and things turn back on and everybody's happy. What I'd mentioned about the balance sheet capabilities of the company and the customer base that we have is absolutely true. But to say that in the long term if residences don't have jobs that won't affect the capital plans of carriers, I think is just wrong. Larger carriers, I think, will weather that better than smaller carriers. But I think ultimately it's all about the economy turning back on. And so there is strong demand. We absolutely in Q1 saw very strong demand. But there was a big push to work-at-home which helped drive that. I think there's definitely heightened awareness of where holes are and the difference between an ultra-broadband customer and not and what that does to their experience. But, ultimately, the second half of the year is going to be materially impacted by whether or not everybody is able to get back to work. And other than -- I don't know -- there are some positive things that definitely will happen regardless. I told you some of these things will start shipping in the first half of next year. We'll see trials on some of these in the fourth quarter of next year is the current plan, but we'll see some positive influences there. But, ultimately, I think the macro environment is going to help weigh into what happens there.

And our next question comes from the line of George Notter with Jefferies.

I guess I wanted to ask about the gross margin performance. It was quite good this quarter. That's impressive this quarter. And I wondered -- you mentioned product mix, geographic mix, you mentioned some operational efficiencies. Could you dig into those items a little bit more and help us understand exactly what's driving the margin performance?

Mike, you want to cover that?

Sure. So, George, I think the shift into the U.S., I think, we've always said in the past has provided higher margins just because you get away from the Chinese competition factor that we see in other parts of the world. So that's one piece of it. Also in the product mix in sales, so depending on what is selling inside of a period, we have some products that have better margins than others. And then when you overlay on that, we have a supply chain and an engineering team that continues to look at our products and our supply chain and attempt to find more efficient ways to build them and to buy the components that go in there. I think those are the major things that helped us to improve it. And, like I said, some of that was actually offset, even a little bit, by some of the supply chain issues that are out there from COVID. That really caused a bit of a squeeze on freight globally as airplanes were no longer available to move many of our components that we tend to use, so the freight costs tend to go up as capacity got restricted. That answers your question?

Yes, that's very helpful. And then just the -- I guess, the COVID-19 impact. I mean, is there a way to quantify, I guess, on both sides -- was there a demand benefit that you guys ticked up over the course of the quarter or I guess towards the end of the quarter? And then also, was there revenue you weren't able to ship because of the supply issues related to COVID and how much might that have been?

Yes. So, let's first start on the demand side. On the demand side, I would say we did see a pickup in order flow. But in many cases -- in fact, I would say in most cases, they were scheduling that order flow out into the quarters that they would want to receive them anyways. So for the most part, what we saw was customers really trying to give us a heads up so we can manage our supply chain and that's been beneficial. So, that's a positive thing just to have that visibility. On the shipment side. There were probably some things that we didn't ship. But, yes, I don't know if that would be -- it wasn't material.

Our next question comes from the line of Michael Genovese from MKM Partners.

I think you said you had 2 U.S. 10% customers in the quarter. And I know normally you have one. So for the second one, can you tell us was it a Tier 1 and Tier 2 or Tier 3?

We really just don't break that out.

Okay.

Mike, I'll defer that to you.

Yes, we usually don't name those customers. So I can't tell you that.

Well, I think, clearly, here there's been in multiple geographies some good new win type of news, particularly, with products that have fiber in the mix as well. And, I guess, my question is, did COVID have any impact on the timing of any of this? Or is that or is COVID kind of irrelevant to the timing of the momentum that you're showing on new wins?

Yes. So on the Tier 1 wins, they take a long time. So this has been an ongoing process with one that's been going on well over a year. In fact, 2 of them have been going on for well over a year. So, no, I don't think the timing -- if anything, we were a little -- we were nervous that COVID would actually delay the timing, just because people weren't able to go in and do the work they need to do in order to close out an RFP and make a decision. That turned out not to be the case. So, no, this -- there is some -- I would say if there is any impact on the acceleration of these -- first of all, we've been talking about Europe opening up first, and kind of jumping to this new architecture first, and that's turned out to be the case. I think one of the reasons is, we've talked about the confluence of the technology with XGS, which allows you to do PON or 10 gig PON effectively out of the same platform and from an infrastructure perspective, effectively the same cost. So I think that that's been a benefit. And the other is the Huawei impact. Without a doubt, Huawei, having the issues that they're having on supply chain and the security concerns has been a benefit as well.

And maybe just my final question. I'm trying to read between the lines of some of the other questions and answers that I've heard. And I just -- I guess I want to ask if this U.S. Tier 1 win, I mean, it sounds to me like it might be with a customer who's been particularly sort of volatile in the past in terms of expectations of big projects that -- some of which are success based, but say we had multiple rounds of issues is that customer -- is that what we're talking about?

No, it's not.

So then final, final question. And is this also tied into 5G back-haul this new win?

Initially, it's not. There are some specific things that we have to do for 5G in relation to latency and timing and things. So initially, no, initially, this is for broadband home and business deployment.

Our next question comes from the line of Paul Silverstein with Cowen.

First off, Tom, like I know you don't disclose the names of the 10% customers. But can you tell us what they represented in terms of total revenue contribution as a percentage of total or in dollars collectively?

Yes, we usually don't break that out as well.

Mike, let me take another crack at this. Can you tell us what percentage of revenue is coming from your top 5 or top 10, however you want to quantify it? I know you don't usually break it out. But customer concentration has been -- I've covered your company for a decade plus. Customer concentration has been a huge issue historically and it leads to some other questions. I think it's important for us to have an understanding of just where you're at today in terms of concentration...

Let me see if I can get some color without Mike shutting me up. I mean, we still have a customer concentration problem. Now the winds that we have that we just talked about explicitly the new large customer in Europe will mitigate that some. We've had some mitigation because of all of the activity that's going on in Australia. But, as you know, this is an industry where even the largest carrier of vendors have problems with customer concentration. If you take a look at what it is that we -- were, we said a lot of -- large percentage of that growth came from which was kind of in the Tier 3 segment and you can probably understand where that may be, which means it is very likely more diversified than not. Hopefully that gives you some color.

Yes, Tom can I ask you this? We looked at your top 5, are they still over 50% of revenue or are they now below 50%, could you give us that?

I don't know -- I literally do not have that customer breakout in front of me. My guess will be, the top 5 of ours, you're probably still -- I would think it's still around 50% or a little bit more.

There is no significant change overtime right in that concentration level. Other than what Tom had said, we had talked about strength in the Tier 3 market, so you are seeing a lot more small guys that are buying from us as compared to the past. But --

And to clarify just a little bit more. A lot of the Tier 3 business goes through distribution. So even though it may be -- in the case of those distributors of ours, even though they show up as one customer, they are really going to hundreds of customers.

And Tom is that the operative number your Tier 3 customer base at this point is the hundreds?

Yes, definitely. Without a doubt.

And so if we look forward to the statements you just made, if we look forward in terms of key growth drivers. The history of that trend has always been these big projects which sometimes come to fruition quite, often they don't. Right. And it's no fault of your own, I assume, it is just nature of the biz. But if we look forward in the next 12 months and over the next 3 to 5 years' time, is it still going to be dominated by definition by these new wins with these new big projects -- big potential projects with big Tier 1 service providers? Are we going to see a more diverse, less concentrated revenue from a growth perspective? How much is one, how much is the other looking forward?

Well, over the last few years, I would say the growth that we have seen or the movement that we have seen and the infrastructure base has been more towards Tier 3. And with the new stimulus programs that are coming on line in the U.S., I would expect that to continue to grow. We are expecting good growth out of the Tier 3 this year. And when I say Tier 3, I probably shouldn't -- I should use a broader term for that, because that includes municipalities, utilities, and it brings up a lot of different customers that really expand what the market size is or at least the diversity in that market. So that's going on. We talked about some of the activity that's going on in Europe. I think right now we have over 14 different alt-net carriers in -- predominantly in the U.K., that are online and have selected us right now and we have similar numbers that are still in play, that are making selections. So that base is going to grow. Now, if we went to Tier 1, and let's say they come in and spend $100 million a year with us, then that will impact that. And the reality is, we want to be able to grow above. And that means there's always going to be some dependency on the project timing of those Tier 1, but at the same time, they allow you to materially move the company forward. And there's really no way to get that large base of business and really pay for the R&D associated with that large base of business unless you actually win some of those Tier 1. So I think it's going to be a mix, and I think at some point in times, I would fully expect the Tier 3 business to be stronger. Right now, that Tier 3 business on the infrastructure side in the U.S. is stronger than the Tier 1 and Tier 2 business. Without a doubt, they had a very good quarter and I would expect that to continue.

So many pauses -- this came up earlier, but if we look at historical projects, ranging from Telmex to NBN, to the cable operators that have, again, have offered significant potential upside, but I think in many cases have not come to fruition. Can you give us an update on your thoughts, your expectations over the next 12 to 24 months from those particular projects? Then I've got 2 quick ones after that.

Okay. So, let me just step back a little bit. Telmex has been wildly successful. The problem with Telmex -- it's well in excess of $100 million, they could buy $45 million or $50 in a quarter, to say that that's not successful. The problem with Telmex is the lumpiness of Telmex. Right? I mean, that's the issue with Telmex, and they're just a very difficult customer. But I -- but I wouldn't consider that not to be strong. With where we did with the MSOs, we still have primary market share with the EPON business. The EPON business just hasn't moved forward. If I look going forward, I mean, the biggest problem is the -- the biggest issue that we've had historically has been centered around one carrier in the U.S. -- one Tier 1 carrier in the U.S. where sometimes we would launch things and they just wouldn't launch. Going forward, we have a new customer coming on board. A very large Tier 1 in Europe coming on board. From what we know about this customer, it's a very well-known customer. They tend to move forward, similar to the other European customers that we have in a very rigid, structured pace. That has been our history with European carriers in general, and I expect no different here. So I would expect that to be of a different tone than the carrier that we had here in the U.S. I don't know if I answered your question.

No, that last 2. Tom, in terms of visibility, you pointed out -- you might point it out that, it sounds like consistent with a lot of other companies, your service providers in order to -- given the supply constraints since better managed their supply chain that they're giving you more visibility than you normally have. The question is, what is your normal visibility? Is it 90 days, the 2 quarters. And what is visibility today? Do you have good visibility into the full year, into the second half, because you're getting better forecast -- more granular from your customers as a general proposition in connection with the COVID-19 impact? And then question for Mike -- I'm sorry, go ahead.

So I would say we're getting better visibility from a handful of customers. And in those customers, yes, we have a solid understanding. Some of them have placed POs going at least into the third quarter. So those we do, but I would say that's still the minority of the customer base that we have. So any trepidation that we have about the second half is based off of -- and by the way they can schedule things out, right? So they're not -- there are very few customers that lock in that and commit to a point that we can't cancel a purchase order. So the trepidation is really around -- and it's not really with the larger carriers. It's really -- with what's happening kind of in the Tier 2 space or kind of that below Tier 1 carrier that there's a little trepidation about. Of course, we're -- our CPE business had a strong quarter in Q1, pretty much across the board -- routers, switches everything. Right? So that's dependent upon small and medium business being at work. So I think there was some build there. But I think in order for that -- and I think that there's definitely a willingness to upgrade infrastructure when things get back to normal, because people see the issues that they had. But this -- kind of it's very murky right now looking past this quarter, even though we have probably more orders and I am just speculating here. But even though we have more firm -- or excuse me POs placed than we would typically have in third quarter at this point in time.

Got it, one last question from me. We respect to gross margin, Mike, any thoughts -- or Tom any thoughts with respect to a reasonable best case over the next 12 to 18 months? If everything went right, what gross margin could go to?

I think we've always targeted low to mid-40s, so I think if you think in the next 12 to 18 months, best case, the middle of that range is 42%-42.5%, I think that's what we've been working towards for a long time to make sure that we've built our products to be able to handle that.

Everything going right would be stronger international business too, and that means that there's a weight on gross margin. So you'd see a top-line growth that would be perfect and you would see a margin growth that would actually marginal, but that would actually come down.

Our next question comes from a line of Bill Dezellem with Tieton.

Actually I have a group of questions. The first one is, what are you seeing in terms of your customer behavior in April and May, and I'm specifically trying to understand if you've seen any indication of COVID-related changes to how they're approaching things?

That's for all customers in general you mean?

It's kind of a general question, unless you want to dive in more specifically somewhere.

Well, I think there's -- I think that it's geography and carrier dependent. So -- and some of that has to do with the rules that are implemented in each of the countries. So in some areas we know that they're wanting to move more towards infrastructure build and kind of getting ready to come out, because they're having a hard time getting into residences or businesses and deploying the service. In other areas, they have beefed up their self-install and are continuing to put -- move forward with upgrades. In almost every case, they are definitely scanning their network and seeing what capabilities are in place right now and trying to proactively offer service upgrades where they can. Although, I would say that the few of mentioned hesitancy to be viewed as profiteering off of the current situation. So they're careful in how they're marketing that. But it's very much region dependent.

Maybe carrying on that region dependent comment. Can you share your qualitative views of the stress on the various systems, just because the workforce now is so distributed compared to, I think, we're all huddled up in offices? And maybe you could take that really by country -- U.S., Germany, Australia, Mexico, U.K. and kind of what the -- again, what's your qualitative view is?

Unfortunately, with that you have to get down to a carrier by carrier basis, because there are multiple bottlenecks. So one, of course, and the one that we're the most focused on is the last mile and the interconnection of that last mile in the mid-haul application. Where we're seeing stress -- there is really -- there is some -- a real gap of capabilities, depending on the region of the country that you may be living in, and I think that, that is causing some heartburn not just within the carrier, but I think within the governments themselves of those different areas. But you're seeing stress in that mid-haul, where there the amount of traffic that's going up. And really I think you're seeing stress pretty much across the board where the upstream bandwidth, unless they're PON is causing problems as well. I think from a total perspective, it's the backhaul portion or the mid and aggregation portion has been helped some by the usage pattern. So what's happened is, it used to be busy time was at night. Busy time was sometimes 8 or 9 o'clock, or maybe even later than that. And what's happened is that, busy time is now moved more towards the daytime. But the capacity requirements itself, although more than what a lot of carriers can handle, is not double, right? It's still -- you are just seeing a more full utilization of the network.

And is there a sense of those countries that I listed, who is in better shape or really more challenged during this environment?

It's not really a country by country thing, it's more of a carrier by carrier thing. So I think, where you have problems or where you have more pronounced problems are where countries have a lockdown on deployments and interactions with customers and there's no capability to upgrade. I think those are the ones that are probably the loudest. And there are parts in Europe that have been deficient in broadband for a long time and those are becoming problematic, although there's not much they can do about it yet, because they can't. I would say the U.S. is actually faring pretty well.

And then one additional question if I may. With the European Tier 1 win -- congratulations, what is your view of what that will lead to for annual revenues when it ramps?

I'll give a sense, because I think it's fair for people to understand the importance. I think this is a very large win for us. It's 10s and 10s of millions a year and it's a long-term contract. So over the term it's 100s and 100s of millions and it's a very big win for us.

[Operator Instructions]. Our next question comes from the line of Tim Savageaux with Northland Capital.

Finally got to my last question after the last dozen or so, but I'll try to focus -- focusing a bit more on that Tier 1 win, and really kind of leveraging up something else that was said in the call, which was, the opportunities driven by Huawei being marginalized, which time you really kind of hit upon that seem pretty hard on the last call and not so much on this one. I would gather that's because you've announced a win, right, as opposed to the potential. So is it fair to assume that major Tier 1 win is partially a function of Huawei being displaced? And when you mentioned a brand new customer, is that brand new for fiber, is that brand new with regard to certain parts?

No, brand new for anything. And, yes. Although -- so I think that -- I think at a minimum, the timing of the opportunities that are presenting themselves in Europe are being influenced by the current situation in relation to Huawei, but the -- in many cases, it's -- there's just -- in some countries there's even as much as legislative action that was being taken to make sure that there's a limit to the amount of impact that, that vendor could have on the network.

And thinking about what you recently announced with Orange. I mean is there a similar type of opportunity in magnitude there over time?

I don't have -- I don't want to say, yes. I know there's a very large opportunity available, but I don't know if it's going to be the same -- the same size. So I think it's too early for us to know that yet.

And my last question is on the rural broadband side. I think you mentioned a number of -- around 70 something percent growth, I just want to come back and get more color and context on that, whether that was your domestic or rural, or what that referred to? And as you see this strength in rural broadband, should we consider that a key factor driving sequential growth in Q2? And as you look forward, do you see the potential for that market to accelerate in '21 as RDOF begins to take off?

Absolutely. The last part of that question is an easy answer, yes. I mean, not only because of RDOF, but because of the current pandemic situation and what that's highlighted. So, yes on that. We saw growth both in European carriers and in the RSP space here in the U.S. I don't honestly know if we break out which one was stronger. We typically report that as a segment, but we saw strong growth in both areas. And we expected the European stuff, because we just have -- I'd mentioned we have 14 alt-nets there. They're just not coming online, so they're just coming up to speed. The only trepidation that I would have and I'll just say this one more time, which is maybe a bad way to end the call, because I see we are out of time. But -- is that -- the visibility out there and how it will impact people is something we don't know yet. So the sooner that we can return to normal business environment, the better off we are. And I'm by no means pushing anybody, because you know we're -- we have been very employee minded here and I applaud that. But that unknown is still unknown. So we'll just have to see as we roll forward and we'll manage accordingly. Hopefully, that answers your question. Okay. Thank you. With that, we'd like to end the call. I thank everybody for joining us on the call today, and we look forward to better times in our call next quarter. Thanks very much.

This concludes today's conference call. You may now disconnect.