1.2 Compare and contrast networking appliances, applications, and fucntions

Question 1

What is a router?

Answer 1

• Routes traffic between IP subnets.
• Routers inside of switches sometimes called “layer 3 switches”.
• Connects diverse network types (LAN, WAN)

Question 2

What is a Switch?

Answer 2

• Bridging done in hardware;
• Forwards data based on data link address (MAC Address)
• Many ports and features
• Could be a multi-layer switch (includes layer 3 routing functionality)

Question 3

What is a firewall?

Answer 3

• It filters traffic by TCP/UDP port number (traditional) or application (NGFW)
• Encrypts traffic (VPN between sites)
• Most can be labeled as layer 3 because they sit at ingress/egress of your network.

Question 4

What is an Intrusion Detection System (IDS)?

Answer 4

Watches network traffic, but only detect and alert admin; will not provide “action” options.

Question 5

What is an intrusion prevention system (IPS)?

Answer 5

Watches network traffic and will alarm, alert, or stop the malicious attack/action from happening (provide options for mitigation)

Question 6

What is a load balancer?

Answer 6

• Distributes the load over multiple servers.
• Typically invisible to the end user.
• Found in web server/data base server farms.
• Provides high fault tolerance.

Question 7

What is a proxy?

Answer 7

• It is a device that sits between the users and the external network.
• It receives the users request and sends the request on their behalf.

Question 8

What is a Network-attached storage (NAS)?

Answer 8

• File-level access
• Networked appliances that contain one or more storage drives, often arranged into logical, redundant storage containers or RAID.
• Accompanying these devices are purpose-built hard disk drives.
• Connect to a shared storage device across the network.

Question 9

What is a Storage Area Network (SAN)?

Answer 9

• Block-level access (change only the blocks of data that need it; not the whole file).
• Is solely dedicated to storage traffic, ensuring high-speed data transfer between servers and storage
• Looks and feels like a local storage device.
• More efficient at reading/writing files

Question 10

What is an Access Point (AP)?

Answer 10

NOT a wireless router; it is a bridge that extends the wired network onto the wireless network; OSI Layer 2 device.

Question 11

What is a controller?

Answer 11

• A hardware device or software program that manages or directs the flow of data between two entities
• They can be cards, microchips, or separate hardware devices.

Question 12

What is a Wireless LAN Controller?

Answer 12

It is a centralized management of access points that allows you to deploy new access points, complete performance and security monitoring, configure and deploy changes to all sites, report on access point use.

Question 13

What is a content delivery network (CDN)?

Answer 13

• It is designed to get data efficiently from one centralized point to an end user
• Geographically distributed caching servers (duplicates the data and users get it from local server).

Question 14

What is a Virtual Private Network (VPN)?

Answer 14

• The ability to secure private data traversing a public network (encrypted communication on an insecure medium).
• Typically requires encryption/decryption access device that is often integrated into the firewall.

Question 15

What is Quality of Service (QoS)?

Answer 15

• “Traffic shaping” or “packet shaping” to provide a higher level of service.
• Ability to control bandwidth usage or data rates.
• Allows you to set important application to have higher priorities than other apps.

Question 16

What is Time to Live (TLL)?

Answer 16

• It is a way to give a system/service/application a timer on when to end/stop
• Wait until traversing a number hops, or wait until a certain amount of time elapses, then STOP (or DROP).
• Will utilize the DIG command to review TTL information (nslookup has been deprecated)

Question 17

What layer is a router located at?

Answer 17

Layer 3

Question 18

What layer does a switch operate at?

Answer 18

Layer 2 - Data Link Layer
- Layer 3 if it has routing capabilities built within hardware.

Question 19

What types of actions make a load balancer properly function?

Answer 19

• TCP offload (Protocol overhead)
• SSL Offload (encryption/decryption)
• Caching (fast response)
• Prioritization (QoS)

Question 20

What are some benefits for using a proxy?

Answer 20

• Caching information
• Access control
• URL filtering
• Content scanning

Question 21

What are some examples where TTL could be used?

Answer 21

1. Drop a packet caught in a loop.
2. Clear a cache.

Question 22

What is the difference for TTL in routing and for DNS lookup?

Answer 22

How it is viewed. Routing will utilize the counting back method and DNS lookup is counting the number of hops to the final destination.

Question 23

What is concentrator?

Answer 23

• It is an encryption/decryption device that is often integrated into the firewall.
• Central connection point for all users accessing a VPN.