tailieunhanh - Remote ISDN Site not Answering

The London network administrator informs you that there is no WAN connectivity. ISDN connectivity has been lost between London and San Jose. After some investigation you contact the San Jose administrator. Based on logs maintained in San Jose, there has not been a successful ISDN session since yesterday when a security audit was performed. Though International Travel Agency (ITA) does not rely on sensitive “topsecret” information, the database of customer information has to be kept confidential. Also, the integrity of the reservation systems is mission-critical. Partners and customers need access to information, but the ability to modify information must be restricted and monitored | Lab Remote ISDN Site not Answering SanJose3 .3 Fa0 0 .3 24 4 1 BRI0 0 51055512340001 51055512350001 4 2 BRI0 0 51055540000001 51055540010001 ISDN Atlas 550 24 London .7 Fa0 0 .1 24 Objective Establish an ISDN BRI to ISDN BRI call from a branch office to a central site. Scenario The London network administrator informs you that there is no WAN connectivity. ISDN connectivity has been lost between London and San Jose. After some investigation you contact the San Jose administrator. Based on logs maintained in San Jose there has not been a successful ISDN session since yesterday when a security audit was performed. Though International Travel Agency ITA does not rely on sensitive topsecret information the database of customer information has to be kept confidential. Also the integrity of the reservation systems is mission-critical. Partners and customers need access to information but the ability to modify information must be restricted and monitored. Step 1 Cable the lab as shown in the diagram. Load the and configuration files. Step 2 Start by turning on debug dialer and debug isdn events while attempting to ping London from SanJose3. Is the call being connected 1-2 Semester 8 Internetwork Troubleshooting - Lab Copyright 2001 Cisco Systems Inc. Step 3 Gather more information by attempting an ISDN session with PPP specific debugging turned on. SanJose3 undebug all All possible debugging has been turned off SanJose3 debug ppp authentication PPP authentication debugging is on SanJose3 debug ppp negotiation PPP protocol negotiation debugging is on London undebug all All possible debugging has been turned off London debug ppp authentication PPP authentication debugging is on London debug ppp negotiation PPP protocol negotiation debugging is on London ping SanJose3 Step 4 Based on the output of the previous commands what are some possible reasons an