Local area network
The first question about attacks in layer 2 has been covered well. The author has covered this question well. Man-in-the-middle attacks are common in this layer and yet this type of attack has been ignored in module 3. ARP spoofing is a common attack that is seen in this layer. The characteristic of a network communication protocol is to send a reply to a host using ARP. The attacker will pose to be the host and send a message to the target machine. This way they shall have got access to the target machine. The author has given an example of how the attack occurs.
The second question has been answered well although the issue of the extent of spanning tree has not been mentioned. Spanning tree attacks are easy to be solved in LAN than in internetworks. This issue was not addressed well. The author has talked of checking the MAC address to see if it has one IP address associated with it. He has not given the process. This is still sufficient as the process of doing this can be given or researched by interested parties.
The second question has also been tackled well since the author gives another significant answer to spanning tree attacks. One thing I will add to this is the fact that spanning tree attacks are becoming common with the networks increased by the day. This attack is common and is targeting networks which are busy. The other attacks that have been answered in question three are sufficient although there are basic attacks. I have a feeling that the author did not talk of other significant attacks that make use of protocols. This answer was good although not complex enough and not insightful.
Question 3 has been extensively tackled by the author. The author first describes how routers play a vital role in networking. The author rightly brings the issue of DNS attacks. One common attack with this is the denial of service attacks. My additional comments is that there is a need to have firewalls to prevent routers from attacks. Use of these security measures will prevent routers from being compromised. There is the issue of DMZ location. This is a mechanism where the routers are put in safe places. This way, routers will be secured.
Question 4 has been answered well. The use of intrusion detection to mitigate attacks is a common phenomena. This is a good step where this mechanism is used to detect any foreign detection in the network. One thought I will add here is that the intrusion detection mechanism should be added to the entry points of the network.
References
Boncella, R. (2006). Secure socket layer (SSL). In H. Bidgoli, A handbook of information security . New York: John Wiley and Sons.
Bosworth, S. (2009). Computer security handbook (5 ed., Vol. 2). New Jersey: John Wiley and Sons.
Huang, S., MacCallum, D., & Du, D.-Z. (2010). Network security. New York: Springer.
Poole, O. (2012). Network security: A practical guide. New York: Routledge.
