online file transfer between two user like skype/gtalk c#

I want creating a online file transfer app. I 开发者_StackOverflow中文版would like the user to drag-drop an item into the file transfer application to initiate the file transfer just like skype or other messengers. can anyone give me good links or sample code for this

One of the most complex part in the "peer-to-peer" data transfer is session initiation, since user can be hidden behind NAT, firewall or proxy server. You probably should take a look at SIP protocol for session initialization - it is used in many VoIP services. Some time ago I found this SIP tutorial rather descriptive, but there are many other docs.

Also, probably it would be useful to take a look at XMPP protocol (GTalk is implemented with this protocol), there is file transfer extension.

MSRP (Message Session Relay Protocol) is designed to send messages and files. It is used by SIMPLE messaging systems. If might be worthwhile investigating.

Konnetic are the only provider of MSRP .NET solutions I know of.