Foundation Summary 87
Foundation Summary
The Foundation Summary is a collection of tables and figures that provides a convenient review
of many key concepts in this chapter. For those of you already comfortable with the topics in
this chapter, this summary could help you recall a few details. For those of you who just read
this chapter, this review should help solidify some key facts. For any of you doing your final
preparation before the exam, these tables and figures will hopefully be a convenient way to
review the day before the exam.
Table 4-5
Standard EIA/TIA-232 Definitions and Codes
Pin Number
Designation
Definition
Description
2
TD
Transmits data
DTE-to-DCE data transfer
3
RD
Receives data
DCE-to-DTE data transfer
4
RTS
Request to send
DTE signal buffer available
5
CTS
Clear to send
DCE signal buffer available
6
DSR
Data set ready
DCE is ready.
7
GRD
Signal ground
8
CD
Carrier detect
DCE senses carrier.
20
DTR
Data terminal ready
DTE is ready.
Table 4-6
Cisco Reserved Port Numbers Used with Reverse Telnet
Connection Service
Reserved Port Range
for Individual Ports
Reserved Port Range
for Rotary Groups
Telnet (character mode)
20002xxx
30003xxx
TCP (line mode)
40004xxx
50005xxx
Telnet (binary mode)
60006xxx
70007xxx
Xremote 90009xxx
1000010xxx