The protocols used to ship the content include HTTP, FTP, SMTP, and IP-based proprietary protocols. In addition there are XML-based protocols like ICE, BizTalk, and so on. In a typical syndication scenario, you have the content in one storage system and one format, and your partner wants the same content shipped to him or her in another format through some transport protocol, and will store the received content in a different storage system. Besides supporting heterogeneous storage systems, formats, and protocols, what is equally important is the ability to effectively manage relationships with your partners. Situations like this mean a good management system is required as an integral part of the syndication solution.
Scalability is a big challenge, and is often a missing piece in most home-grown solutions.
You should ask yourself if your system scales with the number of partners in your network, the volume of content exchanged, and the frequency of updates. The most well-known aspect of scalability is the ability of the server to handle the load. An oft-ignored aspect of scalability, however, is ease of maintaining partner relationships. For two computers to communicate, they have to agree on some standard protocol. On the surface it appears that a binary standard is good for computers to talk to each other.