Recent tragic events in Egypt and France have caused alarm and unrest among travelers and airport operators who are keen to ensure security remains watertight and safe when the threat of terrorism remains at one of its highest and most unpredictable levels.

Where the loophole lies at Sharm el-Sheikh is not yet clear as some claim checks on passengers were lax and not of a comprehensive standard. Others suspect an airport employee was able to plant a device, possibly after a bribe, on board the Metrojet Airbus A321 that was destroyed Oct. 31, shortly after departing the Egyptian resort.

With the attacks in Paris less than two weeks later, all eyes again turned to what can be done to tackle the threat posed to aviation, both in terms of passenger safety and the movement of suspected terrorists as they travel to their targets.

Governments the world over clearly have a role in ensuring standards are met and the latest intelligence is used in tailoring how airports process passengers. In Sharm el-Sheikh, news has emerged that the British Government evaluated security at the airport only weeks before the attack and found no problems.

The immediate response to the attacks in Paris was a lockdown of the country's borders until the situation could be assessed. Easier said than done when in the European Schengen zone, roads and rail lines cross borders without immigration checks.

In the days following 9/11, a similar situation occurred, but airports were soon back in business with the TSA and other countries adapting to provide better coverage and more intensive screening. Since 2001, we now have many more screening employees, full body scanners and the scanning of liquids and shoes as part of the process endured by all passengers.

The threats from these most recent attacks have not necessarily introduced any new threats to airports. After all, bombs have been a threat to aviation since 1933.

However, extra measures put in place from Nov. 21 at Cairo Airport sees cargo destined for New York JFK and London Heathrow airports being banned from passenger flights, and sent by dedicated cargo aircraft instead. In addition, recommendations are that all goods must remain in transit for 48 hours before being transported.

If screening for explosives and weapons are already capable of protecting aircraft from attack, then the challenge could lie in better scrutiny of the intentions of the passengers and their backgrounds and reasons for travel — with an increasing concern over how the movement of refugees within Europe is providing terrorists from Syria with an easy way to travel to targets.

Certain airports will continue to cause concern — especially where suspicions of slack security standards or the proximity of terrorist groups exist, as in the case of Sharm el-Sheikh. Most airlines serving the resort from Britain have cancelled flights until December, with British Airways and easyJet extending this until January, pending reviews of security and the current threat, and others in the region will be under greater scrutiny.

Airports in Paris were already on a higher security alert following attacks earlier in the year, and others at Brussels, Madrid and London have followed suit. All eyes are now on the recommendations that will come once the two attacks, and the ongoing threats have been evaluated.