 |
|
This is why it's fun to review technical books in one's own discipline. Here's a standardized methodology for data transfer protocol design, a field in which I've done a certain amount of work, a standard in existence since the early 1980s, a standard of which I had never heard prior to reading John Larmouth's ASN.1 Complete.
ASN.1 is a International Telecommunications Union-specified metalanguage for designing data packets used in distributed processing. You can employ ASN.1 to design any sort of data packet from simple count-byte strings, to transaction records, to the flattening of high-level language objects. ASN.1 compiler output is language-specific bindings analogous to the output of other IDLs, meant for interface with a vendor-provided platform-specific ASN run time for the targets. The wire-level encoding produced by one vendor's tools in theory interoperates with bindings generated for the same specification by any compliant ASN.1 system.
The point of ASN.1 may seem obscure if you haven't waded through the sort of data packetization that occurs in interchange systems used in medicine, banking, retailing, communications, and all sorts of transaction systems. A plethora of often indifferently factored protocols are in existence haunting programmers around the world. ASN.1 represents a computationally and scientifically more precise analysis and a stab at a general solution to the problem. For the application programmer, ASN.1 transforms packetization from a bit-stuffing chore into a high-level language exercise.
ASN.1 Complete is a personal book. Larmouth has been part of the standards process for ASN almost from its inception. He writes from the inside, personally, like a lecture delivered to a small classroom. He knows his material, and knows how to teach it, carefully cross-referencing mentions of subjects to be covered later and coaching the reader as to what is important to know now and what may be simply accepted until a later, fuller explanation.
The ASN.1 language and its data types, the encoding rules, an overview of ASN.1 development, applications of ASN.1, and the history of the evolution of the standard are some of the topics of discussion in ASN.1 Complete. The exposition is lucid and rich with carefully tailored examples. Not much is left uncovered that isn't better gleaned from perusal of the standards documents themselves, which are downloadable for a fee from the ITU web site (http://www.itu.int/plweb-cgi/fastweb?getdoc+view1+www+29802+0++ASN.1).
ASN.1 Complete is a first-rate book about a very interesting technology, a book authored by an individual uniquely fit for the task. If you're designing application-specific packet protocols to pump over the Internet, this book is a must-read.
OSS Nokalva, a commercial provider of ASN.1 support whose tools are used as examples by the author, has a web site (http://www.nokalva.com/) that offers downloadable trial versions of tools for ASN.1 and links to other ASN.1 information.
-- Jack J. Woehr
| Readability |
|
| Originality |
|
| Organization |
|
| Accuracy |
|
| Consistency |
|
| Depth |
|
| Timeliness |
|
| Editing |
|
| Design |
|
| Overall Value |
|
Explanation of ERCB rating scale: No stars = unacceptable, 1 Star = marginal, 2 Stars = average, 3 Stars = above average, 4 Stars = exceptional.