Trump's wall is only one potential option for border

BUDAPEST, Hungary — From Donald Trump's promise to make Mexico pay for a wall to Kenya's planned 435-mile security barrier along its boundary with Somalia, borders are big business.

"There were more borders and barriers being built in the last 10 years than ever before," says Thomas Tass, the chairman of Borderpol — an organization of border security agents and officials.

The border security market was worth $15.6 billion in 2015, according to estimates from marketing firm Strategic Defense Intelligence. It is expected to grow to $23.7 billion by 2025.

See more on the border wall:

21 PHOTOS
Life along Mexico's border with the United States
See Gallery
Life along Mexico's border with the United States
IMPERIAL SAND DUNES, CA - SEPTEMBER 28: A digger removes sand drifts from the Mexican side of the U.S.-Mexico border fence on September 28, 2016 in the Imperial Sand Dunes recreation center, California. Without daily removal of the sand, the dunes would cover the fence and undocumented immigrants and smugglers could simply walk over it. The border stretches almost 2,000 miles between Mexico and the United States. Border security and immigration issues have become major issues in the U.S. Presidential campaign. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: People meet loved ones through the U.S.-Mexico border fence on September 25, 2016 in Tijuana, Mexico. The U.S. Border Patrol opens the park on the American side in San Diego on weekends to meet through the fence with family and friends through the fence at Tijuana. The park is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 24: Haitian refugees look over donated items at an immigrant center on September 24, 2016 in Tijuana, Mexico. In recent months a surge of Haitian refugees has arrived to Tijuana, seeking asylum at the border crossing into the United States. The center, called the Desayunador Salesiano Padre Chava, serves breakfast to more than 1,000 immigrants daily, many of them deportees from the United States. (Photo by John Moore/Getty Images)
IMPERIAL SAND DUNES, CA - SEPTEMBER 28: A digger removes sand drifts along the U.S.-Mexico border fence on September 28, 2016 in the Imperial Sand Dunes recreation center, California. Without daily removal of the sand, the dunes would cover the fence and undocumented immigrants and smugglers could simply walk over it. The border stretches almost 2,000 miles between Mexico and the United States. Border security and immigration issues have become major issues in the U.S. Presidential campaign. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: People enjoy a late afternoon near the U.S.-Mexico border fence on September 25, 2016 in Tijuana, Mexico. Friendship Park, located on the border between the two countries is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 24: Immigrants, many of them deportees from the United States, eat breakfast at a soup kitchen on September 24, 2016 in Tijuana, Mexico. The center, called the Desayunador Salesiano Padre Chava, is run by a Catholic order of priests and feeds more than than 1,000 immigrants each morning. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 24: People stand in line to cross legally into the United States from Mexico on September 24, 2016 in Tijuana, Mexico. Securing the border and controlling illegal immigration have become key issues in the U.S. Presidential campaign. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: A couple holds hands while meeting loved ones through the U.S.-Mexico border fence on September 25, 2016 in Tijuana, Mexico. The U.S. Border Patrol opens the park on the American side in San Diego on weekends to meet through the fence with family and friends through the fence at Tijuana. The park is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: People enjoy a late afternoon near the U.S.-Mexico border fence which ends in the Pacific Ocean on September 25, 2016 in Tijuana, Mexico. Friendship Park, located on the border between the two countries is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: Mexicans enjoy a late afternoon near the U.S.-Mexico border fence which ends in the Pacific Ocean on September 25, 2016 in Tijuana, Mexico. Friendship Park, located on the border between the two countries is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: A child plays in the Pacific surf near the U.S.-Mexico border fence on September 25, 2016 in Tijuana, Mexico. The nearby Friendship Park is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: Immigrant activists pray at the U.S.-Mexico border fence on September 25, 2016 in Tijuana, Mexico. The U.S. Border Patrol opens the park on the American side in San Diego on weekends to meet through the fence with family and friends through the fence at Tijuana. The park is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: Maria Rodriguez Torres, 70, embraces a grandchild after seeing her other grandchildren for the first time through the U.S.-Mexico border fence on September 25, 2016 in Tijuana, Mexico. She had traveled with family members from Mexico City to see her grandchildren through the fence at 'Friendship Park.' The U.S. Border Patrol opens the park on the American side on weekends to meet through the fence with family and friends through the fence at Tijuana. The park is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
JACAMBA HOT SPRINGS, CA - SEPTEMBER 26: Residents line up to receive free food at mobile food pantry near the U.S.-Mexico border on September 26, 2016 in Jacamba Hot Springs, California. The Feeding America truck delivers to the border town's needy residents twice a month. (Photo by John Moore/Getty Images)
JACAMBA HOT SPRINGS, CA - SEPTEMBER 26: A U.S. Border Patrol vehicle stands guard along the U.S.-Mexico border fence on September 26, 2016 in Jacamba Hot Springs, California. (Photo by John Moore/Getty Images)
JACAMBA HOT SPRINGS, MEXICO - SEPTEMBER 26: A cardboard cutout of Democratic presidential candidate Hillary Clinton is on display at a debate-watching party for supporters of Hillary Clinton at the Yum Yum Chinese restaurant near the U.S.-Mexico border on September 26, 2016 in Calexico, California. People across the country tuned in as Republican Presidential candidate Donald Trump and Democratic candidate Hillary Clinton participated in their first debate. (Photo by John Moore/Getty Images)
HOLTVILLE, CA - SEPTEMBER 27: Mexican farm workers hoe a cabbage field on September 27, 2016 Holtville, California. Thousands of Mexican seasonal workers legally cross the border daily from Mexicali, Mexico to work the fields of Imperial Valley, California, some of the most productive farmland in the United States. (Photo by John Moore/Getty Images)
HOLTVILLE, CA - SEPTEMBER 27: A A Mexican farm worker plows a U.S. farm on September 27, 2016 in Holtville, California. Thousands of Mexican seasonal workers legally cross the border daily from Mexicali, Mexico to work the fields of Imperial Valley, California, some of the most productive farmland in the United States. (Photo by John Moore/Getty Images)
HOLTVILLE, CA - SEPTEMBER 27: A marker stands over an immigrant's grave on September 27, 2016 in Holtville, California. Hundreds of immigrants, many who died while crossing the desert from Mexico into the United States, are buried in a pauper's cemetery. Many of the grave markers simply read 'John Doe.' (Photo by John Moore/Getty Images)
TIJUANA, MEXICO - SEPTEMBER 25: A man looks through the U.S.-Mexico border fence into the United States on September 25, 2016 in Tijuana, Mexico. Friendship Park on the border is one of the few places on the 2,000-mile border where separated families are allowed to meet. (Photo by John Moore/Getty Images)
HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

Researchers from the University of Quebec say there are now at least 65 physical barriers along national borders around the world.

And while Trump's vow suggests there will be no sign of construction slowing, governments around the world are doing more than just putting up walls.

The big question for those watching the borders is how to keep criminals and terrorists out, without infringing on the rights and safety of legitimate travelers.

To accomplish this balancing act, border agencies — and the security companies that supply them — are deploying smarter technology as well.

"Border management programs are basically the biggest business for the security industry now," says Frank Doherty, the European operations director for border technology firm MSA.

The company offers "intelligent fences" that can detect intruders as well as ground sensors and expensive high-range security cameras that can see up to 15 miles away.

MSA has mainly focused on the Middle East, and is now seeing opportunities to increase its business in Europe. But Doherty says Europeans don't want highly visible, fortified barriers that are popular in countries such as Jordan, Saudi Arabia or Oman.

"In Europe they're more covert," he told NBC News. "They want to know the intruder is there but they don't necessarily want to show everybody that they're stopping them coming in."

The largest share of the market is expected to be maritime surveillance with which SID project manager Mainak Kar said is driven in part by demand for unarmed drones, helicopters and patrol vessels to monitor the number of migrants crossing the Mediterranean Sea.

See more on the border wall:

30 PHOTOS
Where the wall already exists along the US-Mexico border
See Gallery
Where the wall already exists along the US-Mexico border
A gap in the U.S.-Mexico border fence is seen outside Jacumba, California, United States, October 7, 2016. REUTERS/Mike Blake 
U.S. customs and border patrol officers inspect a vehicle entering the U.S. from Mexico at the border crossing in San Ysidro, California, United States, October 14, 2016. REUTERS/Mike Blake 
U.S. customs and border patrol officers inspect a vehicle entering the U.S. from Mexico at the border crossing in San Ysidro, California, United States, October 14, 2016. REUTERS/Mike Blake 
Men talk on a street in the town of Calexico, California, United States, October 8, 2016. REUTERS/Mike Blake 
A U.S. customs and border patrol officer stands at a border crossing in San Ysidro, California, United States, October 14, 2016. REUTERS/Mike Blake
Recent arrivals from Mexico wait to board a greyhound bus in San Ysidro, California, United States, October 14, 2016. REUTERS/Mike Blake
Highway 82 towards Douglas, Arizona is seen near Sonoita, Arizona, United States, October 10, 2016. REUTERS/Mike Blake 
Clouds float above the border towns of Nogales, Mexico and Nogales, Arizona, United States, October 9, 2016. REUTERS/Mike Blake 
A sign warning drivers that firearms and ammunition are prohibited in Mexico is seen at the U.S.-Mexico border in Nogales, Arizona, United States, October 9, 2016. REUTERS/Mike Blake
Buildings in Nogales, Mexico (R) are separated by a border fence from Nogales, Arizona, United Sates, October 9, 2016. REUTERS/Mike Blake
An abandoned car sits off the side of a road near Jacumba, California, United States, October 7, 2016. REUTERS/Mike Blake 
A worker makes his way through the water after setting up an irrigation system on an agricultural field, near Calexico, California, U.S. October 7, 2016. REUTERS/Mike Blake
An abandoned car sits off the side of a road near Jacumba, California, United States, October 7, 2016. REUTERS/Mike Blake 
A church at the Museum of History in Granite is seen in Felicity, California, United States, October 8, 2016. REUTERS/Mike Blake
A man drives a tractor plowing a field at sunrise near Calexico, California, United States, October 8, 2016. REUTERS/Mike Blake 
Residential homes are seen next to the fence that borders Mexico, in Douglas, Arizona, United States, October 10, 2016. REUTERS/Mike Blake
Pedestrians wait to cross the street in Calexico, California, Unites States, October 7, 2016. REUTERS/Mike Blake
The town of Bisbee is seen in Arizona, United States, October 10, 2016. REUTERS/Mike Blake
Pedestrians make their way into the the United States from Mexico at the pedestrian border in Nogales, Arizona, United States, October 9, 2016. REUTERS/Mike Blake
A roadside collection of alien dolls and toy UFO saucers is seen next to a roadside residence neat Jacumba, California, United States, October 7, 2016. REUTERS/Mike Blake
A road abruptly ends next to a sign for a cattle ranch near Douglas, Arizona, United States, October 10, 2016. REUTERS/Mike Blake
A boy rides an all-terrain vehicle next Mexican border along the Buttercup San Dunes in California, United States, October 8, 2016. REUTERS/Mike Blake
An old refurbished gas station is seen in Lowell, Arizona, United States, October 10, 2016. REUTERS/Mike Blake 
A man rides a tricycle past a grocery store in a town that borders Mexico, in San Luis Butter, California, United States, October 8, 2016. REUTERS/Mike Blake 
A U.S. customs and border patrol truck drives past the fence that marks the border between U.S. and Mexico, in Calexico, California, United States, October 8, 2016. REUTERS/Mike Blake
A truck drives west towards California along highway 8 near Gila Bend, Arizona, United States, October 10, 2016. REUTERS/Mike Blake
Electronic items are displayed in a shop window in Calexico, California, United States, October 7, 2016. REUTERS/Mike Blake 
A residential home is seen in Nogales, Arizona, United States, October 9, 2016. REUTERS/Mike Blake 
A fence separates the border towns of Nogales, Mexico (R) and Nogales, Arizona, United Sates, October 9, 2016. REUTERS/Mike Blake
HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

"Instead of active aggressive measures like armed patrol boats, electrical fences, a lot of equipment will be surveillance based just to know when and how people are coming in," Kar said.

Security agencies are also deploying a decidedly low-tech, but perhaps the most user-friendly method available: sniffer dogs.

"The dogs are still renowned as the best method of detecting a scene," says Colin Singer, managing director of Wagtail UK. His dogs are trained to sniff out a variety of scents ranging from drugs or tobacco to human beings.

"They're very accurate, so the use of the dogs is a favorite method by border agencies because of their accuracy and speed," he added.

While public opinion may be aligning against globalization and the free movement of people, information sharing among security agencies remains a powerful tool in the fight against crime and terrorism.

Attila Freska, chief operating officer of Securiport, a company that provides security information management services to governments, says by better utilizing all the available data, security forces have something akin to "a crystal ball."

"Most people have a data footprint," he told NBC News. "But even if there is no data footprint, that's a flag. People buying expensive tickets for a flight with cash — that's a flag these days."

Related: Here's What the U.S.-Mexico Border Looks Like Now

Interpol also makes freely available its extensive databases which include the red notices flagging arrest warrants for international suspects.

See more on the border wall:

16 PHOTOS
Touching scenes from the US-Mexico border
See Gallery
Touching scenes from the US-Mexico border

Martha Morales and Juan Manuel Gonzalez Camacho hug their grandaughter Aileen Gonalez and son Adrian Gonalez Morales as they are allowed to meet after a door is opened along the United States-Mexico Border wall during Opening the Door Of Hope/Abriendo La Puerta De La Esparana at Friendship Park in San Ysidro, California on Saturday, November 19, 2016.

(SANDY HUFFAKER/AFP/Getty Images)

U.S. Border patrol agents stand at an open gate on the fence along the Mexico border to allow Adrian Gonzalez-Morales and his daughter Aileen hug his parents Juan and Martha, as part of Universal Children's Day at the Border Field State Park, California, U.S., November 19, 2016.

(REUTERS/Mike Blake)

U.S. Border patrol agents stand at an open gate on the fence along the Mexico border to allow Luis Eduardo Hernandez-Bautista hug Ty'Jahnae Williams and his father Eduardo Hernandez (not in view), as part of Universal Children's Day at the Border Field State Park, California, U.S., November 19, 2016.

(REUTERS/Mike Blake)

Family members hug during a U.S. Border Patrol sponsored visit at the U.S.-Mexico border fence in Tijuana, Mexico, on Saturday, Nov. 19, 2016. The U.S. Border Patrol, in coordination with immigrant rights groups, opened the metal gate so that previously selected families could visit for several minutes.

(Photographer: David Maung/Bloomberg via Getty Images)

A woman in Friendship Park in San Diego, California, U.S. speaks with children across a fence separating Mexico and the United States, November 12, 2016. Picture taken from Tijuana, Mexico.

(REUTERS/Jorge Duenes)

U.S. Border patrol agents stand at an open gate on the fence along the Mexico border to allow Edith Hernandez and her daughter Yvette hug Maria Plata-Colin, as part of Universal Children's Day at Border Field State Park, California, U.S., November 19, 2016.

(REUTERS/Mike Blake)

People in Friendship Park in San Diego, California, U.S. are seen behind a fence separating Mexico and the United States, November 12, 2016. Picture taken from Tijuana, Mexico.

(REUTERS/Jorge Duenes)

Relatives separated by immigration hug at an open gate on the fence along the Mexico and U.S border on Universal Children's Day in Tijuana, Mexico November 19, 2016.

(REUTERS/Jorge Duenes)

Relatives separated by immigration hug at an open gate on the fence along the Mexico and U.S border on Universal Children's Day in Tijuana, Mexico November 19, 2016.

(REUTERS/Jorge Duenes)

Luis Hernandez hugs his Father Eduardo as they are allowed to meet after a door is opened along the United States - Mexico Border wall during Opening the Door Of Hope / Abriendo La Puerta De La Esparana at Friendship Park in San Ysidro, California on Saturday, November 19, 2016.

(SANDY HUFFAKER/AFP/Getty Images)

Members of the Gonzalez family hug each other and react as they encounter at the gate of the U.S.- Mexico border fence opened for a few minutes on November 19, 2016 in Playas de Tijuana, Mexico. The door opening was organized by pro-migrants NGOs and local authorities in coordination with the United States Border Patrol.

(GUILLERMO ARIAS/AFP/Getty Images)

Relatives separated by immigration hug at an open gate on the fence along the Mexico and U.S border on Universal Children's Day in Tijuana, Mexico November 19, 2016.

(REUTERS/Jorge Duenes)

A U.S. Border patrol agent stands at an open gate on the fence along the Mexico border to allow Laura Avila and her daughter Laura Vera Martinez hug Maria Socorro Martinez Lopez, as part of Universal Children's Day at the Border Field State Park, California, U.S., November 19, 2016.

(REUTERS/Mike Blake)

A young boy joins his family members as they hug during a U.S. Border Patrol sponsored visit at the U.S.-Mexico border fence in Tijuana, Mexico, on Saturday, Nov. 19, 2016. The U.S. Border Patrol, in coordination with immigrant rights groups, opened the metal gate so that previously selected families could visit for several minutes.

(Photographer: David Maung/Bloomberg via Getty Images)

Relatives separated by immigration hug at an open gate on the fence along the Mexico and U.S border on Universal Children's Day in Tijuana, Mexico November 19, 2016.

(REUTERS/Jorge Duenes)

HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

The organization also has a database of stolen and lost travel documents that lists some 70 million passports, according to Royce Walters, assistant director for terrorism and border security at Interpol.

He says it takes a fraction of second for a border agent to get information from the database, just by scanning a passport.

"Pretty much before you can finish swiping it, it's already hit the database and come back with information as to if there's a problem," he says.

Walters says another available database has millions of sets of fingerprints, "everything from small-time petty thieves, all the way up to terrorists that were identified during the war in Afghanistan and Iraq."

Despite such advances, sometimes a physical barrier is deemed necessary.

Hungary put up hundreds of miles of fencing along its borders with Serbia and Croatia in 2015 to stop waves of migrants who were crossing over to gain access to other European Union countries.

Hungarian Interior Ministry Deputy Secretary Matyas Hegyaljai told NBC News that the country, which typically received about 20,000 illegal migrant crossings each year, saw 400,000 crossings in 2015.

When border patrols and police were not enough to contain the influx, the country took action.

"We have an obligation to defend not only Hungary, but the European Union," Hegyaljai said.

Hegyaljai suggested the fence could come down if the situation improves. "This is not a wall, forever, like on some other border lines," he added.

Tass, with Borderpol, says the challenges faced by Hungary provided a "litmus test of what the border management community will encounter in the months and years ahead."

ISIS has also changed the equation, and put pressure on the so-called Schengen system — which allows travelers free passage to other EU countries without passport checks.

The Islamist group has urged its fighters to use migrant routes to enter Europe. That includes two suicide bombers who had trained in Syria before taking part in the attacks Paris in November 2015.

"The real challenge for the entire civilized global community is the foreign fighters," says Peter Vincent, an assistant director for international policy at Borderpol.

But Vincent, who is a former official in the U.S. Department of Homeland Security and Department of Justice, says it is "unfortunate" to see European countries building fences and worries that strict controls put in place to stop terrorists will instead impact on lawful travelers.

"The trick for all of us is to have the proper safeguards in place to detect and capture that very small minority of committed terrorists, while the same time providing asylum and refugee status ... to those that are truly fleeing terrorism, not committing acts of terrorism," he added.

According to Securiport's Freska, different legal structures between countries and privacy concerns mean there is no perfect solution to border security.

"You look at water and how it flows," he said. "You may build a dam in one area, it will flow around as we see over and over again."

Read Full Story

Sign up for Breaking News by AOL to get the latest breaking news alerts and updates delivered straight to your inbox.

Subscribe to our other newsletters

Emails may offer personalized content or ads. Learn more. You may unsubscribe any time.