Next Generation Wireless Applications: Creating Mobile Applications in a Web 2.0 and Mobile 2.0 World, 2nd Edition

5.9 XML GLUE

Earlier in this chapter, we looked briefly at XML. It is fast becoming a universal way of describing data that passes from one application to another. This technique is not bound to any particular protocol or network, nor is it bound to any particular network architecture, whether CS, P2P or any other. From an applications perspective, as long as applications can produce and consume XML, then we don't really care how the XML passes between collaborating agents, nor where they sit in the network.

Realising the universality and network-independence of XML, it is tempting to suggest the notion of a virtual XML ‘highway’. This is just an academic concept, but as we progress through the book, the idea that all software applications exchange XML messages becomes a powerful archetype by which to think about software collaboration. To implement such a highway globally would require an addressing and routing scheme. Of course, one already exists with IP, and with the advent of IPv6, we now have a big enough address space to accommodate a unique address for every device on the planet. However, we have already alluded that IP is not always the best networking option, particularly for P2P transactions within the device network (more on this later).

It is likely that all wireless applications will eventually swap information using XML vocabularies. Currently, this is not the case. For example, we have already seen that the RTTTL tone format is not XML (nor is SP-MIDI). In fact, ...