What The OSI model or layer is implemented on the following issues?

Question

The OSI model is a useful tool in troubleshooting a network because it enables you to isolate a problem to a particular software module or piece of hardware. In this project, after reading the description of a problem, identify the OSI model layer or layers that are most likely involved.


● A computer won’t connect to the network. After some investigation, you find that the patch cable isn’t terminated correctly.


● A computer can access resources on the local LAN but not on a different subnet. You find that the computer’s default gateway isn’t configured correctly.


● You can ping a computer you’re trying to transfer files to via FTP, but you can’t communicate by using FTP.


● All computers connected to a particular hub have lost network connectivity You determine that the hub is the problem.


● You receive an encrypted text file, but when you open it, the text is unreadable. You determine that decryption didn’t take place as it should have.


● You check some statistics generated by a network-monitoring program and discover that an abnormally high number of CRC errors were detected.


● One of your servers has been exhibiting sluggish network performance. You use a network-monitoring program to try to evaluate the problem. You find considerable TCP retries occurring because the server is being
overwhelmed by data, and packets are being discarded.


● A user is trying to connect to another computer, but the logon attempt is continually rejected.


● You try to access a Linux server to share files by using NFS. You can communicate with the server, but the shared files don’t appear to be available.


● You inspect a computer that isn’t able to communicate with other computers.

Answer 1

1. Layer 1, physical

2. Layer 3, network

3. Layer 7, application

4. Layer 1, physical

5. Layer 6, presentation

6. Layer 2, Data link

7. Layer 4, transport

8. Layer 5, session

9. Layer 7, application

10. Layer 3, network



But you should really do your own homework! = )

Answer 2

Layer 7: utility - it rather is the layer that actual interacts with the working gadget or utility on each occasion the person chooses to flow information, examine messages or carry out different community-appropriate activities. Layer 6: Presentation - Layer 6 takes the information provided via the utility layer and converts it right into a undemanding format that the different layers can understand. Layer 5: consultation - Layer 5 establishes, maintains and ends communique with the receiving gadget. Layer 4: delivery - this residue maintains flow administration of documents and provides for blunders checking and restoration of documents between the gadgets. flow administration skill that the delivery layer seems to work out if documents is coming from extra effective than one utility and integrates each utility's documents right into a unmarried flow for the actual community. Layer 3: community - the way that the information would be sent to the recipient gadget is desperate in this residue. Logical protocols, routing and addressing are dealt with right here. Layer 2: documents - in this residue, the right actual protocol is assigned to the information. additionally, this style of community and the packet sequencing is defined. Layer a million: actual - it rather is the point of the unquestionably hardware. It defines the actual features of the community at the same time with connections, voltage ranges and timing.

Answer 3

I don't want to sound patronising but it is important that you understand this stuff if you want a career in comms. If you don't want a career in comms why are you learning this?



The OSI model while it might seem like some arbitary set of rules is a mighty useful tool to have wrapped your head around if you are ever likely to have to troubleshoot anything. WHILE the OSI model does not correspond precisely to TCP/IP networking, the principles of it are pretty much identical whether you're networking data, voice, video or anything else.



Take my advice and read the book again. It's worth it