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Bionic Buffalo Tech Note #104: Summary of Pegasus/ISA versus DSM-CC Specification Coverage

The definitions commmon to both architectures include:

Protocols:
User-Network Session Protocol, the subset of 21 common message types, and 4 common
resource types, for setting up and tearing down sessions (this is the subset of DSM-CC U-
N Session supported by Pegasus SSP)
User-Network Download Protocol, including the data carousel

In other words, DSM-CC and Pegasus have very little in common. By rough page count, only about
15% of the DSM-CC specification (mostly portions relating to User-Network Session and Download
protocols) is applicable to the Pegasus architecture.

(Note: The lists above were taken from the 1998 revision of the DSM-CC specification, and from the
Pegasus IDL version 1.4 as published by Time Warner around August 2002.)

Potential Interoperability

Pegasus is not DSM-CC. However, the two architectures can be interoperable. Bionic Buffalo has
written Tech Note #103, Introduction to Pegasus Client Support, to describe how interoperability is
achieved on the client. A future document will provide an equivalent discussion of interoperability on
the server.

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