Endace DAG 6.1S, Руководство пользователя

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EDM 01-11v8 DAG 6.1S Card User Guide
©2005 36 Version 8: May 2006
7.0 DATA FORMATS OVERVIEW
In this chapter This chapter covers the following sections of information.
•
Data Formats
•
Timestamps
7.1 Data Formats
Description The DAG 6.1S card uses the ERF Type 1 POS HDLC Variable Length
Record. Timestamps are in little-endian [Pentium native] byte order. All
other fields are in big-endian [network] byte order. All payload data is
captured as a byte stream, no byte re-ordering is applied.
Table Table 7-1 shows the generic variable length record. The diagram is not to
scale.
timestamp
timestamp
type flags rlen
lctr wlen
(rlen - 16) bytes of record
Table 7-1. Generic Variable Length Record.
Data format The following is an overview of the data format used.
Data Format Description
type: This field contains an enumeration of the frame
subtype. If the type is zero, then this is a legacy
format.
0: TYPE_LEGACY
1: TYPE_HDLC_POS: PoS w/HDLC framing
2: TYPE_ETH: Ethernet
3: TYPE_ATM: ATM Cell
4: TYPE_AAL5: reassembled AAL5 frame
5: TYPE_MC_HDLC: Multi-channel HDLC
frame
6: TYPE_MC_RAW: Multi-channel Raw link
data
7: TYPE_MC_ATM: Multi-channel ATM Cell
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