Type abstraction in formal protocol specifications with container types

In this paper, we propose a seamless integration of the concept of "(universal) container types" into Formal Description Techniques (FDTs), which introduces a new concept of data abstraction. We show how this syntactical and semantic extension increases the expressiveness in the area of component reuse, without sacrificing the formal precision of the FDT. The ideas are exemplified for Estelle, but apply to other FDTs in the protocol domain (e.g., SDL) as well. Furthermore we will demonstrate, how this extension increases the capability to formally specify the static and even the dynamic packet composition and decomposition of pre-existing protocols (like TCP/IPv6 or XTP).