Saturday, February 27, 2016

Networking Questions for 2016 - Part 1

A new set of half dozen networking questions to get you thinking.  

I'm going to expand into SDN, Security and NVF questions over the next few months to keep things current :-) Enjoy.

1. What process is used to check whether packets have been received when using IP?

A) Acknowledgments
C) Windowing
D) Flow control
E) None

2. What is the dotted decimal format of the loop back address?


3. What is the reserved address space for a Class C network?

A) -
B) -
C) -
D) -
E) - 

4.  Where is the start-up configuration file held in a router?

C) Routing table

 5. What is the maximum size of an Ethernet packet when the frames have ISL tagging?(Include the size of headers and CRC)

A) 64 bytes
B) 1500 bytes
C) 1518 bytes
D) 1522 bytes
E) 1548 bytes

 6. What are the three layers of the Cisco hierarchical model?

A) Core layer, Network layer, Access layer
B) Core layer, Distribution layer, Access layer
C) Physical layer, Network layer, Transport layer
D) Media Layer, Transport layer, Application layer

Free Cisco labs for CCNA, CCNP and CCIE students!
Presented by René Molenaar - CCIE #41726

1. Answer E 

Trick question to start the series :-). IP provides no form of error correction/acknowledgements.

2.  Answer B is a special reserved IP address which is used as a host's loopback address. Messages sent to loopback address do not get placed on the LAN, instead they are re-routed by the host's own network adapter back to the receiving end of the TCP/IP stack.

3. Answer D

 4. Answer A

The IOS software in Cisco devices looks for a valid configuration file stored in NVRAM. which is called as startup-config. If a startup-config file is not in NVRAM, the router will start the setup-mode configuration upon boot up.

5.  Answer E

Cisco's proprietary VLAN tagging (ISL) has a maximum frame size of 1548 bytes.
IEEE 802.1q VLAN tagging has a maximum frame size of 1522 bytes.

 6. Answer B 

Core layer: Considered the backbone of the network (high-end switches, high-speed cables). Concerned only with speed and reliable delivery of data. No packet filtering happens here.

Distribution layer (Workgroup layer): Ensures packets are properly routed between subnets and VLANs using LAN-based routers and Layer 3 switches.

Access layer (Desktop layer): Deals with connecting workstations to the network with switches and hubs.

How did you go?  Stay tuned for more in the coming weeks and months  :-)

 Follow effective action with quiet reflection. From the quiet reflection will come even more effective action.
― Peter Drucker