Technical data

When data becomes available at a tracepoint that you are tracing, CTF collects
that data in the form of a trace record. The trace record consists of the data
itself (user data and protocol data), together with additional information about
the trace record, such as:
• Its size
• The time at which it was collected
• The name of the tracepoint from which it was collected
Depending on how you are using CTF, trace records may either be written to a
trace file for later analysis, or they may be displayed on your terminal as they
are collected.
When you display trace records (either as they are collected, or from a previously
created trace file), they are analyzed. This analysis involves:
• Translating the binary data in the trace record into a user-readable format,
which may be ASCII, hexadecimal, or octal
• Formatting the data to show the various components of protocol data, user
data, and trace record information
The analysis performed on a trace record depends on the tracepoint from which
it was collected. The routines that analyze trace records are supplied with the
networking software that supports the tracepoints from which they are collected,
and form part of that product’s CTF support.
1.3 Networking Products that Support CTF
You can only use CTF on Digital’s networking products. The tracepoints from
which you can collect information depend on the product you are tracing. Not
all Digital’s networking products have tracepoints; check the Software Product
Description to see if your product supports CTF.
The following networking products support CTF:
DECnet/OSI for VMS
DEC WANrouter 100/500
VAX P.S.I. for DECnet/OSI for VMS
VAX WAN Device Drivers for DECnet/OSI for VMS
See the appendixes to this manual for details of the tracepoints that are provided
by these products.
1–2 Introduction to CTF