The technology that changed air travel (2018)
retool.com
retool.com
If you just look up some of these concepts and protocols, it looks cryptic but doable, but it's harder than it looks, and there's also some less-straightforward opcodes. Although there's documentation, it's not always enough, and consulting experts from IBM was necessary. There was also building regression test suites from captured real-world protocol traffic, to verify that you can mimic the behavior of the parties.
Perhaps of side interest to HN: ITA stated publicly that they decided they had to use Lisp, to have the complex undertaking be tractable. Which meant they hired a ton of Lisp people, and got a lot of high-powered people who normally wouldn't want "legacy mainframe" anywhere near their resume.
Even when the internet became popular, the first search engines (like Travelocity and Kayak) really sucked.
It wasn't until ITA Software came about that there was an honestly good and useful travel search engine. ITA is really the "technology that changed air travel" in the internet age.
As with all B2B backbone systems, consumers are hardly ever aware that the even exist. Power grids, pipelines, shipping, ERPs, airline booking all are systems people ignore until something goes wrong. And those systems are shielded from consumers by multiple layers of middleware and middlemen that hide the complexity of things.
Good for consumers, the downside is that the actual knowledge of hoe things works gets more and more concentrated on a very small group of experts that have to keep the lights on while proverbial Jane in Accounting or Bob in marketing don't like the UI and tech bro Chad prevers to move fast an brake things with management assuming agile is the solution to everything.
Around 2007-2008, Sabre went on an acquisition spree and bought the major clients of Amadeus around the world. Then proceeded to force them to use Sabre instead (quite inferior results and heavily biased towards AA and other related companies). And finally when the 2008 crash happened, did massive restructuring and layoffs on such companies. Even for profitable ones. Some were sold afterwards for pennies on the dollar. The hit and run on Amadeus worked.
Got to love central bank backed corporations. (0% interest loans of unlimited amounts)
Sabre is an invincible Goliath. Amadeus is a David just trying to survive.
Source: I worked for one of those companies at the time.
You're right that existing GDS systems have done nothing interesting for decades, though. Did you know that Sabre charges their customers on a per-API call basis? Airlines like to minimize the number of times they call into Sabre for that reason. You might imagine that the Sabre people are not especially motivated to make their API simple and modular enough to lower the number of calls required.
The original cloud service!
Also, most IATA standards I've read are littered by the statement "or a different convention by bilateral agreement between the parties" multiple times per page, so documentation only gets you halfway there. Having actual customers and defining how each customer deviates from the standard is the harder half.
I don't know for sure that Lisp would be required (for the functional aspects?), but I can see the appeal.
As far as lack of documentation, it's not really any worse than any other field. Sometimes there's huge, detail-filled document from some organization like the IATA, with lots of revisions, sometimes the documentation is out of date, and some times it's missing. The worse problem is that all the original knowledge retired with people long ago, and the game-of-telephone version we have now is also walking out the door, because of pandemic-related disruptions in the travel industry generally.
It's a huge industry, and airlines are motivated by both profit and regulation to accommodate all kinds of things you wouldn't necessarily think of.
Speaking of profit, yes, extra bag charges, seat changes, and upgrades are explicitly revenue generators. They aren't just covering the extra cost, airlines will upsell you a variety of extras (would you like fries with that? some dipping sauce maybe?) in pursuit of profit.
1 https://en.wikipedia.org/wiki/EDIFACT
2 https://www.thesun.co.uk/travel/5703214/boarding-pass-codes-... although the trend towards electronic boarding passes and scanners means the letters and numbers are disappearing into the barcode or Aztec code.
When entities like Expedia started coming online, it was a major sea-change. At my first job after grad school in the 80s, the company actually had a travel agent on premise in our main building to help employees book both business and personal travel.
This all sounds great on paper, and I'm sure it reduced the travel expense line in Google's budget. But unanticipated effect was that you had engineers making mid 6-figure total comp spending way too much of their time finding travel deals so they could come in below the median. Talk about penny wise and pound foolish.
Except they don't really. I often like to see the tradeoffs laid out for me and, if it's not obvious, maybe spend a bit of time thinking about it--especially if I'm mixing in some personal time as well.
As I wrote in another comment there are specialist services that deal with mostly pleasure travel in particular locales but that's different from the traditional travel agent who mostly booked cruises, flights on major carriers, tours, and business or resort hotels.
1.) Online booking systems are good for the 95% case (or maybe more). But I've spent way too much time wrestling multi-jaw international trips requiring non-major airlines into submission. To be sure, not sure how good our corporate travel would have been but maybe they'd have saved a lot of legwork and reservation would have been in one place.
2.) I've done things like long distance walking trips in England. Absolutely worth it to have someone book the places, arrange luggage transports, any shuttles, etc.
You can imagine how a third party entity would make constant searches for seat and flight availability, spurred by all the possible permutations of airports and flight schedules. This flurry of activity rockets up the number of "looks" to the number of actual "books".
These third parties might be Online Travel Agencies trying to get around their own contractual limits with the GDS, or it might be companies that sell the schedule and fare data as competitive intelligence.
For now, the GDS' and airlines try to solve the problem with anti-bot solutions to keep contractual overages low.
If someone could instead solve the underlying structural problem (computational intensity? cost of compute? cost of running a GDS? offer free fare and schedule data to all?), they could probably crack open a multi-million dollar market opportunity.
AirNZ is a Sabre customer, and their travel agents used it directly for years, but had such a steep learning curve that they built a wrapper for it - still a command line system, but divided the screen into quadrants to display different colors information, and some macros that automated some common tasks.
Despite the simplification, it still took 2 weeks full time training before agents could use it, and even then the first week was as a buddy system where you had someone helping you for a week (most of that time was learning the system, but also included time to learn all the three letter airport codes and other acronyms used for reservations).
Some old timers would switch down to Sabre for complicated tasks because it was faster than using the wrapper and it was amazing to watch them interact with the system.
One colleague I worked with had been with the airline for nearly 50 years and remembered pre-computer days where the ‘booking system’ was just a big shared blackboard.
> GDS systems, however, did not adapt with them.
Air New Zealand was one of the earliest airlines to experiment with different fare classes (premium economy, ‘saver’ fares with no baggage etc) and better tools (flexible date search), I remember being involved with RFQs with Sabre and competitors to enable a flexible date search of +/- 3 days the quotes coming back for sometime like 9 months of development for a crazy amount like $2M. Maybe doesn’t sound like much now, but back in 2000, revenue from online sales hadn’t yet even crossed $1M per year, so that single feature cost more than 2 years of online revenue.
This was the incentive for AirNZ to invest early in their own internal software development which was a very smart move- as it allowed us to experiment and give customers features that even our larger competitor (QANTAS) couldn’t match.
I’m so happy I got to experience all of that- definitely the highlight of my career to date.
One interesting aspect of the GDS is that they made efforts to have a better GUI, with point and click options, to facilitate the steep learning curve of the tool.
That effort was botched because of the existing use base was so well used to the DOS-like command interface that they simply ignored the GUI. A similar thing happened to Bloomberg and their terminals.
When I moved to tech and had to deal with experience revamps I always took this example with me. Even though you might have a better experience to users, do not underestimate the lock in of the current users to your existing UI.
Another great example of that is the now infamous Dig revamp....
There’s been a bit of a movement in Europe to ban short haul connections since most European hubs are connected to rail, the issue is usually that the connection leaves a lot to be desired (e.g. rail is not in the controlled areas of airports, often there is no baggage through handling)
All software is command-driven