XML appliances have gone by many names over the years, including SOA gateways, XML gateways and SOA appliances. Regardless of its handle, the technology has been used to successfully create messaging formats and share data on the Web. Today, however, XML's role is changing, and it is not the only messaging protocol game in town.
In the late '90s, XML appliances were a useful and simple messaging protocol solution, said Jason Bloomberg, president of ZapThink, a Dovel Technologies company. Today, Bloomberg says application programming interface (API) management is an important part of the XML appliance story. Bloomberg discusses the transformation of XML appliances over the years and where the future of the technology is headed in this Q&A.
What were the initial problems XML appliances were designed to solve?
Jason Bloomberg: The whole idea of XML appliances really started rolling in the '90s. It became clear back in 1997, 1998, that XML was going to be very useful as a messaging protocol, because it was more robust than the binary alternatives that were used at the time. It was evident then that a network issue was arising because of all the messages on the network. So a bunch of startups, which specialized in building the actual chips, started crafting silicone-based solutions for accelerating XML-based operations. Those led to the XML appliances market, which really started to get rolling around 2001, 2002. The focus at that time was on core XML operations like parsing, encryption, decryption, transformation and others, so it made sense to have chips that would focus on those.
The story continued to evolve and became more of service-oriented architecture (SOA) appliance after the mid-2000s. As people began to understand how to implement SOA, the whole area branched out into three categories that are essentially the successors of the XML market. These are general-purpose content, API management and cloud appliances.
What are the functions of each of these three middleware appliances?
Messaging is not just about XML anymore.
president of ZapThink
Bloomberg: There are general-purpose content devices, which include antivirus appliances and other sorts of compliance-related appliances, security-related appliances that deal with the content level. This category is not specifically XML; it could be any kind of content. It could be email appliances, search appliances; there are a variety of different appliances for these things.
The second category is API devices. It's a new word for what we called, 10 years ago, services. [First there was] Web service devices, and then there were SOA devices, and now they are [called] API management. API management is one of the strongest areas that is essentially the next-generation XML appliance.
The third area is cloud devices. These are cloud management and compliance devices that, even though they say cloud, they go in the company's DMZ [demilitarized zone] in the network and essentially enforce cloud-related policies.
What is the backstory on APIs?
Bloomberg: API management is such an important part of the story, it's important to understand the context for this notion of an API. Back in the '90s we called them APIs, and then we called them services, and now we call them APIs again. Usually, when marketers come up with terms, they always like new terms, the old ones go out of style and come up with something new, but in this case they just dusted off an old one and brought it back. It's kind of strange. Long live the APIs!
What is the state of the XML usage today?
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What does the future hold for XML appliances?
Bloomberg: It's going to be interesting to see where the cloud device is going. When I teach two-day classes, people always scratch their head and say, 'How do you put appliances in the cloud?' That sort of misses the point on what these things do. They go in the corporate network and manage in the cloud. The next obvious question is, 'What if you just go home and access the cloud there?'
The fact that you have to put it in your own network is a limiting factor. The next question is, how can these become virtual appliances in the cloud where it's less about the platform and more about the functionality of the device?
Is there anything that could happen that would make the cloud not have such an impact on the middleware appliance market?
Bloomberg: The vendors who are investing in silicon, building the chips themselves -- they make money by selling physical hardware so they don't want to come up with an alternative solution that means customers don't have to buy hardware. There is always going to be a market push by companies to buy physical hardware to put in their own network to do all of these different things. As long companies are still managing their own networks, there will always be a role for this content-level device.