Foundation Summary 417
Foundation Summary
This section contains a table that provides a convenient review of many key concepts in this
chapter. If you are already comfortable with the topics in this chapter, this summary could help
you recall a few details. If you have just read this chapter, this review should help solidify some
key facts. If you are doing your final preparation before the exam, Table 11-2 is a convenient
way to review the day before the exam.
Table 11-2
ISDN Terms
TE1
A device that has an ISDN component built into it, ie an ISDN external modem.
TE2
A device without an ISDN component, ie a Laptop.
TA
Terminal Adapters convert computer electrical signals into ISDN signals.
NT1
A termination point for a 2 wire local loop.
NT2
An ISDN switch, ie PBX, Madge ISDN switch, Adtran 550
Table 11-3
ISDN Reference Points
R
Represents a device with no ISDN capability, ie a PC or Laptop, a 2500 router without
any ISDN interfaces.
S
Defines the reference points between user terminals and a NT2, an example being an
ISDN telephone
T
Represents the interface between NT1 and NT2 devices. An example is the PBX
connection to the NT1
U
Defines the two-wire interface between the NT1 and the PSTN.
Table 11-4
Remote LAN Access
Remote Control
Think of PC Anywhere. A PC is always left on at Headquarters to dial into -
insecure.
Remote Node
Think of dialing into Headquarters, logging on to a server, and using Windows
Explorer to map disk drives more secure than Remote Control.
Table 11-5
Routers and where they fit
Telecommuter Routers
700, 800, 900, 1000, and 1600 Series
Branch Office Routers
1600,1700, 2500, 2600 , 3800 Series routers
Regional Office Routers
4500, 4700, 3600, 7200, AS 5000 Series
Central Site
7200, 7500, 7000, AS 5000 Series
87200333.book Page 417 Wednesday, August 22, 2001 2:53 PM