expectable abilities in communication and encryption

[Mo]

Hi list,

I am a student working on a service for mobile devices (mainly cellular
phones). Since I got no experience in development of embedded devices,
I have some open questions about what abilites I can expect from these
devices. As I understand, developers of embedded devices in the
majority of cases aspire using integrated modules to delegate more
complex tasks (e.g. communication stacks or encryption) to.

While developing the communication requirements I came across the
following questions:

1) Is there any real chance of using SOAP in communication with mobile
embedded devices?

2) As I was advised, embedded systems preferably use UDP for
communication because of less requests to resources. Is this correct?

3) Regarding security issues I would appreciate communication over TLS.
Is there any known integrated "TLS-on-a-chip"-solution I could require
to be used in the embedded device? (I think encryption tasks in
software might be beyond of the usual cellular's resources, right?)

4) Asuming point 2) is right: During my investigation I stumbled on a
protocol named DTLS (DatagramTLS) providing TLS for UDP Communication.
Does enybody know of some implementation of this technology in an
embedded chip?

So far for now.

Thank you very much for any help.

Greetings
Moritz

PS: If you think this posting ist OT in this group I would appreciate
any hint for the right place.