CCIE Routing and Switching Exam Certification Guide, Third Edition

Appendix F. Key Tables for CCIE Study

Chapter 1

Table 1-2. Ethernet Cabling Types

Type of Cable	Pinouts	Key Pins Connected
Straight-through	T568A (both ends) or T568B (both ends)	1 1; 2 2; 3 3; 6 6
Cross-over	T568A on one end, T568B on the other	1 3; 2 6; 3 1; 6 2

Table 1-3. Ethernet Header Fields

Field	Description
Preamble (DIX)	Provides synchronization and signal transitions to allow proper clocking of the transmitted signal. Consists of 62 alternating 1s and 0s, and ends with a pair of 1s.
Preamble and Start of Frame Delimiter (802.3)	Same purpose and binary value as DIX preamble; 802.3 simply renames the 8-byte DIX preamble as a 7-byte preamble and a 1-byte Start of Frame Delimiter (SFD).
Type (or Protocol Type) (DIX)	2-byte field that identifies the type of ...