Support Notes

[Neo]

Hi,
Sau đây là một số điểm cần nhớ khi sắp đi thi ccxx/support.

1. ISDN Notes

TE1: ISDN enabled - no TA needed
TE2: TA needed
NT1: ISDN transmission device, like a modem
LT: Line terminator at each end of wires
ET: Exchange termination at exchange

R: TA - TE2
S/: TE2/TA - NT1
T: NT1 - NT2 if both exist
U: NT1 - LT
V: LT - ET

ITU I.430: Physical layer
ITU Q921: Data Link Layer (Link Access Protocol)
ITU Q931: Network Layer (Call setup)

RJ45 pin 3&6: Tx
RJ45 pin 4&5: Rx
RJ45 pin 1&2: +/- 3V (Power Source)
RJ45 pin 7&8: +/- 2V (Power Sink)

*Multiple TEs can be connected to a line simultaneously
*Service Profile Identifier SPID used by SP to ID devices
*If SPID needed & not set, L2 OK but no calls can be initiated
*Cisco support signaling formats 5ESS (AT&T), DMS1000, NI1
*NT1 powered from mains, other ISDN equip. powered from NT1
*2 x 64K B, 1 x 16K D, 48K framing & sync. Total = 192K!!

Initiate Call Procedure:
SETUP -> (router requests connection)
SETUP ACK <-
CALL PROCEEDING <- (Idle while call routed through ISDN N/W)
ALERTING <- (May not see)
CONNECT <-
CONNECT ACK ->

Initiate Disconnection:
DISCONNECT -> (Sent to remote router)
RELEASE -> (Sent to local exchange)
RELEASED <-
RELEASE COMPLETE ->

Receive Call
SETUP <-
CALL PROCEEDING ->
ALERTING ->
CONNECT ->
CONNECT ACK <-

Receive Disconnect
DISCONNECT <-
RELEASED ->
RELEASE COMPLETE <-

(Còn tiếp)
Frame Relay
Protocols
Routing Protocols
Routers/RPs
Switch Diagnostic
Network Management
Support Resources
Troubleshooting