Key Terms
545
Remember what the CIR is in Frame Relay. The CIR is the rate, in bits
per second, at which the Frame Relay switch agrees to transfer data.
Remember the commands for verifying Frame Relay. The show frame
relay
lmi command will give you the LMI traffic statistics exchanged
between the local router and the Frame Relay switch. The show frame
pvc
command will list all configured PVCs and DLCI numbers.
Remember the PPP Data Link layer protocols. The three Data Link
layer protocols are: Network Control Protocol (NCP), which defines the
Network layer protocols; Link Control Protocol (LCP), a method of
establishing, configuring, maintaining, and terminating the point-to-
point connection; and High-Level Data Link Control (HDLC), the MAC
layer protocol that encapsulates the packets.
Understand what the basic standards of ISDN provide. The ISDN
standards define the hardware and call-setup schemes for end-to-end
digital connectivity.
Remember what the total bandwidth of BRI provides. Basic Rate Inter-
face provides two 64Kbps bearer (B) channels and one data (D) channel of
16K, for a total of 144Kbps.
Remember what the command show isdn status provides. Shows if
your SPIDs are valid and if you are connected and communicating with
layers 1 through 3 information to the provider's switch.
Key Terms
B
e sure you are familiar with these terms before you take the exam:
Backward-Explicit Congestion
Notification (BECN)
circuit switching
Basic Rate Interface (BRI)
committed information rate (CIR)
central office (CO)
customer premises equipment
(CPE)
Challenge Authentication
Protocol (CHAP)
Data Link Connection Identifier
(DLCI)
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