Networking Exam 2

What technology allows a computer to run both IPv4 and IPv6


1. Datagram
2. DHCP
3. Dual-IP stack
4. VPN Resource

Dual-IP stack

What is packet switching? Why is it important to the data exchange process?

**Packet switching allows blocks of data to be transferred across multiple networks. It’s important to the data exchange process because it identifies its own path to reach the destination and doesn’t require any dedicated connection for transmission. It allows for data information to be sent and received by other servers.**

When a DHCP server is configured, which two IP addresses should never be assignable to hosts? (Choose two)'


1. broadcast address on the network
2. IP address leased to the LAN
3. IP address used by the interfaces
4. network or subnetwork IP address
5. manually assigned an address to the clients Resource

**broadcast address on the network, network or subnetwork IP address**

Which IPv6 address is valid?


1. 2001:0DB8:0000:130F:0000:0000:08GC:140B
2. 2001:0DB8:0:130H::87C:140B
3. 2031:0:130F::9C0:876A:130B
4. 2031::130F::9C0:876A:130B

**2001:0DB8:0000:130F:0000:0000:08GC:140B**

The following are DHCP components except:


1. DHCP client
2. DHCP router
3. IP address pool
4. Subnet

**DHCP router**

List two advantages and one disadvantage of using DHCP:

**Advantages: supports multiple scopes and implementation does not require additional costs.**

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**Disadvantage: packets cannot travel across routers**

What was the main limitation that IPv4 had that necessitated the creation of IPv6?


1. IPv4 was too slow. As technology advanced, a new and faster IP system needed to be created.
2. We ran out of IPv4 addresses and needed more.
3. There was only unicast in IPv4 and we needed a way to send packets to multiple nodes so we added broadcast messages in IPv6.
4. IPv4 had everything that IPv6 had, but it used a more confusing system. IPv6 streamlined the IP addresses.

**We ran out of IPv4 addresses and needed more.**

 


1. DHCP is a service that runs somewhere on a network (often on a router in a home network) and is used to assign IP addresses to the connected devices. It does so by leasing the IP address to them. What is a lease and why is the lease necessary?

**The DHCP lease is a temporary assignment of an IP address to a device on the network. It’s useful to limit the length of time that a client can use the IP address with other clients. It prevents unused clients from taking up IP addresses where there are more clients than addresses.**

What process does the DHCP automate? How does the DHCP automate the process mentioned above?

**It automates the process of configuring devices on IP networks and using DNS, NTP, and other communication protocols based on UDP or TCP. It runs at the TCP/IP stack to assign IP addresses to DHCP clients and to allocate TCP/IP configuration info to DHCP clients.**

Mention two disadvantages/advantages of DHCP?

**Advantages: supports multiple scopes and implementation does not require additional costs.**

**Disadvantage: packets cannot travel across routers and has no secure mechanism for authentication of the client.**

1. What is the default subnet mask for a Class C IP address?


1. 255.0.0.0
2. 255.255.0.0
3. 255.255.255.0
4. 255.255.255.255

**255.255.255.0**

1. What is the IPv4 Address Class for 192.168.64.190?


1. A
2. B
3. C
4. D

C

Write the default mask for subnet classes A, B, and C. Include the CIDR notation for the IPV4 address and the binary representation for the default mask.

Rank subnet classes A, B, and C from the one that supports the largest number of hosts to the one that supports the least.

**Class A- 16 million** \n **Class B - 65,000** \n **Class C - 254**

1. Which one is a class A IP address?


1. 110.168.190.8
2. 129.16.55.13
3. 168.212.178.204
4. 191.168.132.47

**110.168.190.8**

1. Match the 3 classes to their subnet masks: 

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1. Class A 255.255.255.0
2. Class B 255.0.0.0
3. Class C 255.255.0.0

1. Which Classful IP Class can have the most amount of hosts on a single network?


1. A
2. B
3. C
4. E

A

1. Which of the following host ranges is the IP address 10.145.100.6/27 part of?


1. 10.145.100.0 - 10.145.100.32
2. 10.145.100.0 - 10.145.100.255
3. 10.145.100.1 - 10.145.100.30
4. 10.145.100.1 - 10.145.100.255

**10.145.100.1 - 10.145.100.30**

1. Fill in the blank: Subnetting travels a (shorter/longer) ____ distance by narrowing down the (ip address/ speed)___ tp certain devices.

shorter; ip address

With classless IP, classes are completely irrelevant. True/False

False

How is subnetting an important concept to classful and classless IP?

**It divides IP addresses into parts: the host(computer) and the other identifies the network to which it belongs**

1. Which of the following is true about Distance Vector Routing?


1. Distance vector routing contains entries for each router in the subnet.
2. It eliminates the infinity problem
3. It is a dynamic routing algorithm
4. It is a static routing algorithm

**It is a dynamic routing algorithm**

What are some applications that utilize the Shortest Path Algorithm?

**Google or Apple maps, GPS navigation**

1. What is the maximum Number hop count allowed in Routing Information Protocol (RIP)?


1. 10
2. 15
3. 20
4. In RIP, the number of hops does not matter.

15

In RIP what happens when a router crashes or a network connection is severed?

**The router stops sending updates to its neighbors or stops sending or receiving updates along the severed connection. It will drop the route and let the rest of the network know about the problem.**

Why does link state routing require more CPU utilization than distance vector routing?

**Because link-state protocols build a complete map of the topology. Every router has a copy of the network map that is regularly updated.**

1. What is "flooding" in link state routing?


1. The process of gathering information about a router's neighbors
2. The process of calculating the cheapest route with Dijkstra's Algorithm
3. The process of initializing a database prior to the traversal of the routers
4. The process of configuring the correct protocol to use before routing starts

1. The process of gathering information about a router's neighbors

1. Where do the routers using OSPF protocol get the information to build Link-State Database?


1. ABRs
2. Hello Packets
3. LSAs
4. OSPF Interface

LSAs

True or False: OSPF is a type of Distance Vector Routing Protocol.

false, **It’s a link-state protocol**

1. Which layer of the OSI model does the BGP fall into? Explain why this is the case.

**It operates on the OSI Transport Layer (Layer 4) to control Layer 3.**

List three differences between BGP and OSPF in terms of the network size they work on, their structure, and scalability

**BGP is more scalable, is Mesh in their structure, and routes within a single AS.**

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**OSPF is used to find the shortest route available, OSPF is essential in a hierarchical structure, and less scalable.**

Why is UDP sometimes called an Unreliable Data Protocol?


1. UDP has a lot of security vulnarabilities.
2. UDP does not attempt to solve the corrupt data packets.
3. UDP has a very slow performance.
4. This statement is false, UDP is a reliable protocol.

**UDP has a lot of security vulnerabilities.**

Which of the following is tru about TCP?


1. TCP check data for errors.
2. TCP performs re-tranmsission in case of missing data packets.
3. TCP makes sure that the packets are arranged in order before they reach the applicaiton.
4. All of the above.

All of the above

Which of the following is found in a TCP header but not UDP header?


1. Sequence number
2. None
3. Destination port
4. Checksum

Sequence number

How many bytes is the default header size per packet in TCP?

20 bytes

1. How many clients can use the port number 80?


1. None
2. One
3. Fifteen
4. As many computers that exists

As many computers that exists

Why do connction requests have to be accompanied with IP addresses along with the port numbers?

**Connection requests are accompanied by those two components to identify devices, applications, or services on the network that the request is intended for.**

True or False: TCP (a.k.a. Transport/Command/Push) is a protocol at the transport layer which does not verify that the data has been recieved by the client and is also known as the "fire and forget" protocol.

False

1. What is the main difference between TCP and UDP on the transport layer.

1. One of them uses port numbers to access specific parts of a server while the other does not.
2. One of them cares about the recieving machine getting all of the data sent while the other does not.
3. One of them breaks sending data into smaller chunks known as packets and the other does not.
4. One of them is a newer version of the other with obviously enhanced characteristics like increased bandwidth and speeds.

What is a socket?

**A socket is a data communication endpoint that provides a connection-oriented communication service between 2 endpoints on a network.** 

How does TCP handshake work?

**It’s a 3-way communication process used to establish a connection between a client and a server. It works in 3 steps: the client sends a synchronization message to the server saying that it wants to establish a connection. After the server receives that message, they send a synchronize acknowledge message. After the client receives that message, they respond with an acknowledge message.**

1. Which of the following language is mostly used for socket programming?


1. C++
2. Python
3. Java
4. All of the above

All of the above

1. Which layer is socket programming?


1. Network layer
2. Application layer
3. Between transport and application layer
4. Physical layer

**Between transport and application layer**

Write a URL for a website with an SSL/TSL certificate

**https://www.berea.edu**

List 2 level 1 errors and 2 level 2 errors in the SSL Alert Protocol:

**Level 1 error (Warning):**

* **Bad certificate, when the received certifiacte is corrupt** 
* **Certificate expired: when a certificate has expired**

**Level 2 error (Fatal):**

* **Bad record MAC: when an incorrect MAC was received**
* **Illegal parameters: when a field is out of range or inconsistent with other fields**

True or False: Both the internet and the web operate on the client-server model

1. World Wide Web is another term for:


1. Another name for the internet
2. Collection of world wide information
3. A collection of information pages interlinked
4. Worldwide connection of a computer

1. A collection of information pages interlinked

What are the 4 DNS servers involved in loading a webpage?

**DNS recursor, root name servers, top-level domain nameservers, and authoritative nameservers.**

Among the 4 DNS server, which one is responsible for containing all DNS source records?

**Authoritative nameservers**

1. When traveling from the top application layer to the bottom physical layer, how does the packet get translated?


1. from electronic signals into alphabetic text
2. from alphabetic text into electronic signals
3. from alphabetic text into numerical symbols
4. from numerical symbols into electronic signals

from alphabetic text into electronic signals

1. Preventing phishing attempts is crucial to not become a threat for the attackers. Describe some of the actions that you would take to prevent phishing attacks.

**Never provide personal information, don’t click on fishy emails or text message links, and get anti-phishing add-ons.**

How is HTTPS different from HTTPS?

**HTTP lacks security to encrypt the data while HTTPS provides SSL or TLS Digital certificate to secure the information between a server and a client.**

There is a difference in TCP handling between HTTP/1.0 and HTTP/1.1. What does a closed TCP session mean?

Explain the difference between Passive FTP and Active FTP.

**In Passive Mode, all connections are opened from the client to the server.**

**In Active mode, the server opens the data connections calling back the client.**

What mode of FTP alleviates some of the responsibility for firewall configuration from the client-side.

**Passive FTP**

1. What Email protocol is used to forward an email to a server?


1. SMTP
2. POP
3. IMAP
4. b & C

**SMTP**

1. What is true about the POP Email Protocol (choose all that apply)?


1. POP Email Protocol Is used to retrieve Emails from the server.
2. POP can be accessed across multiple devices.
3. POP Email Protocol does not require a constant connection to the server.
4. Emails are downloaded locally on the PC.

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How many machines are needed to use ssh?

1. What happens when you try to ssh into an IP address that doesn't exist?

1. The connection times out on port 22.
2. The connection responds with permission denied.
3. The screen flashes: no host with that address.
4. The server continuously requests a password.

What layer of the OSI model does FTP take place in?

1. Which of the following is NOT an email protocol?

1. POP
2. SSH
3. IMAP
4. SMTP

What are the two subsystems of emails? Explain briefly what each subsystem does.

Why is using NFS to allow a file-sharing system is better than using USB drives? List two reasons.

In server farm we are introduced to load balancing. What is load balancing and how is TCP header lookup related to it?

Describe the role of a server in the client-server model.

When running Berea College network, we need various types of servers. One of them could be print server for printing services. List 3 more necessary types of servers and their purpose in the network of Berea College.

1. Which organization would be most likely to use a mainframe?


1. A retail store
2. A restaurant
3. A hospital
4. A sports equitment manufactuer

A hospital

List two reasons why someone might choose to use a commodity server over a mainframe:

What hardware component is most commonly used to store data in server farms? Why is this the case?

What physical medium do we use when transmitting data to and from server farms? Why would we use it over other mediums?

What are the differences between an application server and a web server?

True or False: A server can refer to a physical machine, a virtual machine, or a server services performing software.

1. Regarding virtual and physical serves, which of the following is true (Select All that Apply)?

1. Virtual servers have higher processing speeds and handle heavy workloads better than physical servers.
2. Physical servers are always easier to manage than virtual servers.
3. Virtual servers are software-based environments that emulate all the functions of physical servers.
4. Physical servers are generally less powerful than virtual servers.
5. Multiple virtual servers can run on one single physical server and share physical hardware.

How are SSH and a virtual machine related?

Why is it bad for a VM to use a self-signed certificate?

What is the difference between a container and a VM?

What does a cloud server allow a VM to do?

What OS's can run a VM?

When would a container be better than a VM?

Name the two different types of VMS and explain the difference.

What are 3 advantages of VMS?

What is the main difference between Virtual Machines and Containerization?

What are some applications that utilize “The Cloud”?

What is Latency and why is it a problem in some Cloud Applications?

What are some of the advantages that the Cloud Storage (DropBox) provides?

1. Elizabeth opened her laptop and started online shopping during Black Friday but was unsure about purchasing a sweater. She waits until Cyber Monday to continue her purchase on her laptop and notices her items are still in the shopping cart. Which of the following online tracking tools is being used?

1. Cookies
2. Fingerprinting
3. Cross-device tracking
4. All of the above

True or False: Device fingerprinting is the technology allowing to track users across multiple devices such as tablets, smartphones, and laptops.

List two advantages and disadvantages of Social Media use.

1. What is phubbing?

1. Harrassing or otherwise bullying someone anonymously on the Internet
2. Looking at a device during conversation and avoiding social interaction
3. Feeling self-conscious about your body due to exposure to images of other people's figures
4. Pretending to be someone else on the Internet

What is internet censorship? What are some pros and cons of it?

1. Are there any problems with freedom of speech on the Internet you are seeing? What should we do to reduce the consequences of it?

1. In some countries, certain information is prohibited/restricted to be accessed over the internet.


1. What do we call this process?

 

 


2. Mention three types of information that are prohibited/restricted under such laws.

Explain why prohibition/restriction of such information can sometimes cause controversies?

What is net neutrality?

List three basic elements of copyright

When online companies pay ISPs to give their data traffic preferential treatment that is called .....?

3. If you’re experiencing slow speeds or intermittent connectivity when not many users are connected to the same network. there’s a chance that you’re experiencing:

1. Network Congestion
2. Running out of data
3. Network Throttling
4. None of the above