Drag and Drop

Question 1

Explanation

To remember which type of cable you should use, follow these tips:

– To connect two serial interfaces of 2 routers we use serial cable
– To specify when we use crossover cable or straight-through cable, we should remember:
Group 1: Router, Host, Server
Group 2: Hub, Switch
One device in group 1 + One device in group 2: use straight-through cable
Two devices in the same group: use crossover cable

For example: we use straight-through cable to connect switch to router, switch to host, hub to host, hub to server… and we use crossover cable to connect switch to switch, switch to hub, router to router, host to host… )

Question 2

Question 3

Question 4

Explanation

The question asks us to “begin with the lowest layer” so we have to begin with Layer 1: verify physical connection; in this case an Ethernet cable connection. For your information, “verify Ethernet cable connection” means that we check if the type of connection (crossover, straight-through, rollover…) is correct, the RJ45 headers are plugged in, the signal on the cable is acceptable…

Next we “verify NIC operation”. We do this by simply making a ping to the loopback interface 127.0.0.1. If it works then the NIC card (layer 1,2) and TCP/IP stack (layer 3) are working properly.

Verify IP configuration belongs to layer 3. For example, checking if the IP can be assignable for host, the PC’s IP is in the same network with the gateway…

Verifying the URL by typing in your browser some popular websites like google.com, microsoft.com to assure that the far end server is not down (it sometimes make we think we can’t access to the Internet). We are using a URL so this step belongs to layer 7 of the OSI model.

Question 5

Explanation

To remember which type of cable you should use, follow these tips:

– To connect two serial interfaces of 2 routers we use serial cable
– To specify when we use crossover cable or straight-through cable, we should remember:
Group 1: Router, Host, Server
Group 2: Hub, Switch
One device in group 1 + One device in group 2: use straight-through cable
Two devices in the same group: use crossover cable

For example: we use straight-through cable to connect switch to router, switch to host, hub to host, hub to server… and we use crossover cable to connect switch to switch, switch to hub, router to router, host to host… )

Note: The correct cable type of PC – Router should be crossover. But it was use for switch – switch (which is surely correct) so this question contains a bug.

Question 6

Question 7

Question 8

Explanation

CDP runs on all media that support Subnetwork Access Protocol (SNAP), including LAN, Frame Relay, and ATM physical media.

Reference: https://www.cisco.com/c/en/us/td/docs/ios/12_2/configfun/configuration/guide/ffun_c/fcf015.html

The most important benefit with LLDP-MED is that it is an open standard -> It support for third party devices.

LLDP supports Topology change notification, which sends a notification if a device is added or removed.

Reference and comparison between CDP and LLDP can be found at: https://www.cisco.com/en/US/technologies/tk652/tk701/technologies_white_paper0900aecd804cd46d.html

Question 9