Telecoms run in the blood for Shay Walsh, managing director of BT Ireland.
His maternal grandfather was a telegraphy operator on Valentia Island, sending messages between Europe and America during World War I. His father worked in the GPO managing landline accounts for the Department of Posts and Telegraphs, forerunner to Telecom Éireann and Eir.
When Walsh left DCU with an electronics engineering degree, it seemed natural that he'd end up in telecommunications. But the sector was on the cusp of an Irish revolution thanks to a new concept - competition.
He joined Denis O'Brien's Esat Telecom in 1995 when it had barely 50 staff.
His first job was as a field engineer installing phone lines in businesses. Esat at that time leased network access from Telecom Éireann - and then, to the State operator's chagrin, installed 'auto dialler' units to channel long-distance traffic to their own services.
"It was an easy enough sell in those days. We could halve your international phone bill. The pitch was short and sweet - and effective," he recalls.
The two companies battled each other from the High Court to the European Commission for much of the decade. Esat accused Telecom Éireann of overcharging for access, while the latter criticised the 'auto dialler' tech as against the rules.
"Telecom Éireann had perhaps 10,000 employees, was very set in its ways and not used to competition. We faced a pretty hostile environment because we were seen as an upstart and almost getting round the legislation," he says. "We brought innovation and an entrepreneurial spirit."
Esat in 1996 founded a mobile phone firm, Esat Digifone, in partnership with Norway's Telenor. A year later, Esat listed on the Irish, London and New York stock exchanges ahead of the market's full deregulation in 1998.
Esat laid its own fibre optic network, starting in Dublin 2 and Dublin 4 in 1997, then to Sandyford and Citywest. By 2003, Dublin was connected with Waterford, Cork, Limerick, Galway and Sligo.
Walsh oversaw this fibre rollout first as manager of Esat's network management centre, then as head of networks reporting to the board. Laid chiefly alongside rail lines, that network expanded to encompass more than 2,500 kilometres of backbone fibre used to fire fixed-line telephony and internet traffic.
"That is the foundation for our business today, where all our traffic transits," he says.
When Telenor launched a takeover bid for Esat in late 1999, O'Brien's firm wooed British Telecom as a white knight. BT paid €2.4bn and christened the newly delisted firm Esat BT. It was rebranded BT Ireland as the parent merged it with Northern Ireland operations.
The mobile arm Esat Digifone, meanwhile, was merged into BT Wireless. It was rebranded 02 and, in 2005, sold to Spain's Telefonica as another mobile operator, Hong Kong-owned Three, entered the Irish market. Eight years later Three acquired 02's Irish unit from Telefonica.
"It's amazing to see the rich tapestry now of telecommunications companies," Walsh recalls. "I'd never have thought this was possible 25 years ago, when we were fighting tooth and nail just to exist."
BT Ireland built much of Three's early capabilities and remains a key partner today.
"We ran the original contract to design, plan and roll out their network for them. We built their mast sites, planned and acquired them and built them out as a turnkey contract. Today we deliver fibre to a lot of their mast sites. We backhaul their traffic over our network. We provide them field services and a lot of their IT back office operations as well."
Sky is BT Ireland's other top wholesale customer.
"We do all of Sky's voice broadband internet services. They do the billing and customer service but we do the physical implementation and the back-office support for their network."
Walsh estimates that such wholesale business drives about 40pc of revenues, equivalent to €170m in its most recent financial year. It's just struck a deal with Pure Telecom to help that challenger to expand services nationwide.
Since BT Ireland sold its consumer and small business portfolio to Vodafone in 2009, its main focus has become providing telephony and internet services to more than 200 of Ireland's biggest businesses. These commercial operations generated around €250m last year, chiefly from a core of global tech firms reputedly including Amazon, Apple, Facebook and Twitter.
"We service most of the US technology companies in Ireland," he says, declining to name them.
"You could name any of the larger multinationals landing in Ireland and we service those, particularly in voice services. These global organisations would need large contact centres in Ireland.
"Those contact centres service EMEA and in many cases most of the world. We deliver phone service, phone ranges and Freefone numbers, and deliver them into contact centres in Dublin and Cork."
Top domestic clients include Airtricity, Bank of Ireland, US Bancorp's Elavon, Glanbia, Kerry Group and Penneys.
AT&T and Verizon are BT's key competitors in this space.
"Global customers need phone calls initiated in Germany or Asia to be answered in Ireland. BT has a presence in over 180 countries," he says.
"We have the network to pick up that call from the local carrier in any of those countries and deliver it to the call centre here. None of the local companies have that capability.
"Obviously AT&T and Verizon have that, but they don't have the large domestic network that we have in Ireland So we have an advantage here over the other global carriers, and an advantage over the local carriers that don't have global connectivity. We sit in a sweet spot between those two."
Walsh directed the wholesale side of BT Ireland, then its business sales side, before his promotion to managing director in 2015. That coincided with BT's decision to integrate Northern Ireland operations back into the UK parent company as part of its £12.5bn acquisition of the mobile phone firm EE.
Today Walsh oversees more than 650 employees. Two-thirds are in Dublin, the rest spread across Cork, Galway, Limerick and Waterford.
All five offices have been shut since mid-March in keeping with Covid-19 precautions.
Walsh - who lives in Castleknock with his wife, the former 'Glenroe' actress Eunice McMenamin, and their three children - says he misses his daily cycle through Phoenix Park and along the quays to BT offices on Grand Canal Plaza.
But one element of BT Ireland operations here must stay fully staffed on site because of the crisis - the nation's 999 emergency services hotline.
Since 2008, BT has run the Emergency Call Answering Service. BT employs 65 operators in Ballyshannon, Co Donegal, and Navan, Co Meath.
They average 180,000 calls a month but that spiked to 215,000 when Covid-19 struck.
"People were calling the service because they really didn't know who to call. The HSE hotline hadn't been advertised and awareness was low.
"Calls for other emergencies dropped because of lockdown. The usual traffic - road accidents, nightclub brawls, thefts - stopped. But we experienced a spike anyway because people needed help understanding Covid. 'Do I need an ambulance? Do I need a guard?' People were confused about the public health policies."
BT Ireland gets a fixed profit regardless of call volume.
"If you dial 999 from a Three mobile number, Three carry the cost for that call. The network operator pays," he explains. "We run the network and the call centre technology and the people who answer the calls. We run an open book. We show our costs.
"The simple maths is this: if there's a million calls in the year, we divide our costs by a million and that's the cost per call. The more calls there are, the more each call handling fee goes down."
BT Ireland's growth depends on deepening relationships with the country's top tech and financial services firms.
"Our first task is to acquire more growing companies that need complex roll-outs of digital networks," he says. "Although price is important, it's not the reason they stay with us, it's the service and the uniqueness we offer."
BT Ireland's clients stay an average of nine years.
"We've very low levels of churn. The magic sauce here is to keep a customer through multiple contract renewals and cross-sell to them.
"Telecoms is very competitive, so customers expect a 10pc to 25pc discount to renew their contracts. That means, even if you retain the same number of customers, your business declines over time, because every time they renew their contract, you have to take a haircut.
"The solution is to cross-sell to existing customers, so they'll renew with us with more products."
Products include installation and management of third-party software, and security monitoring of traffic.
"We don't want just any customer. We target those who have complex digital transformation requirements. We help firms ditch their legacy network and bundle their voice and data together. If you get 'denial of service' or phishing attacks or get hacked, we'll protect your traffic."
Walsh says BT Ireland, like its parent, is a potential takeover target - for the right price.
Last year other Irish media outlets reported that BT Ireland had been sold for €300m to a London equity firm. BT Ireland immediately denied this. The talks fizzled.
But Walsh says telecoms is rarely quiet on the mergers and acquisitions front.
"We're focused on our next three- to five-year plan as a subsidiary within BT. But we're a sought-after organisation in Ireland. Rumours are going to knock around.
"Somebody once said in BT that any part of BT is for sale at the right place. We see speculation in the UK press at the moment that BT itself is being bought or looked at for sale to an equity house.
"We have a mergers and acquisition group in BT Centre that will entertain approaches from time to time. At the moment I'm not engaged in anything other than running the business, driving it forward, and trying to deliver the numbers."