EXIPC (fka Epoxy)

A queuing layer that allows the Internet Information Server (IIS) and store processes (Inetinfo.exe and Store.exe) to shuttle data back and forth very quickly. This is required to achieve the best possible performance between the protocols and database services on a server running Exchange 2000. Conventional applications require the processor to switch contexts when transferring data between two processes.

Exchange Server 5.5 incorporated protocols such as Network News Transfer Protocol (NNTP), Post Office Protocol 3 (POP3), and Internet Messaging Access Protocol (IMAP) directly into the Store.exe process, so data transfer was very efficient. The Exchange 2000 architecture separates the protocols from the database for ease of management and to support future architectures. [Exchange 2000]