Defining Networks With The OSI Model

Layer 3 (Network Layer)

A ___________ switch is one that uses logical addressing to determine data paths.

Router

A layer 3 switch is similar to a ___________.

Layer 1 (Physical Layer)

A standard such as 100Base-T refers to which OSI layer?

Layer 6 (Presentation Layer)

A user has connected to a Web site. The information that is sent to that user's computer is encrypted in an encoded format. This change to the data occurs at the ___________ layer.

21

Port ____________ is used by the File Transfer Protocol.

Registered

Ports 1024-49,151 are ports used by vendors for proprietary applications. They are known as ________ ports.

Port Range 1024-49-151

Ports used by vendors for proprietary applications. These must be registered with the IANA (e.g., Microsoft registered 3389 for use with the Remote Desktop Protocol). Registered Ports

Physical Layer, Data Link Layer, Network Layer, and Transport Layer

The first four layers of the OSI Model are what?

Data Link Layer, Network Layer, Transport Layer, and Application Layer.

The four layers in the TCP/IP Model are what?

Internet Control Message Protocol (ICMP)

The manager of IT asks you to ping his laptop to see whether your computer can find it on the network. In this scenario, the __________ protocol is being implemented.

Inbound Ports

These are used when another computer wants to connect to a service or application running on your computer.

Outbound Ports

These are used when your computer wants to connect to a service or application running on another computer.

Session Layer

This layer governs the establishment, termination, and synchronization of sessions within the OS over the network and between hosts-for example, when you log on and log off.

Session

This layer of the OSI Model uses the Protocol Logon/Logoff.

Physical

This layer of the OSI Model uses the Protocols 100Base-T & 1000Base-X and uses Hubs, patch panels, & RJ45 Jacks as devices.

Data Link

This layer of the OSI Model uses the Protocols 802.3 & 802.5 and its' devices are NICs, switches, bridges, & WAPs.

Presentation

This layer of the OSI Model uses the Protocols Compression & Encryption.

Application

This layer of the OSI Model uses the Protocols FTP, HTTP, POP3, & SMTP and its' device is the Gateway.

Network

This layer of the OSI Model uses the Protocols IP, ICMP, ARP, & RIP and uses Routers as its' device.

Transport

This layer of the OSI Model uses the Protocols TCP & UDP.

Port Range 0-1023

This range defines commonly used protocols (e.g. FTP utilizes port 21 to accept client connections.) Well-known ports.

Arp -a

What is the Address Resolution Protocol Command?

Presentation

What layer in the OSI model is used to encrypt data?

OSI Reference Model

What model is used to describe how data communication occurs between hosts?

Dynamic Ports

What ports are defined above 49,152?

Physical

Which layer deals with the serial transfer of data?

Application

Which layer in the OSI model covers HTTP, FTP, and RDC?

Network

Which layer in the OSI model covers routing between networks?

Data Link

Which layer in the OSI model do MAC addresses and switches use?

Physical

Which layer in the OSI model includes the cable and network adapters?

Transport

Which layer in the OSI model is included in the TCP/IP model?

Network

Which layer in the OSI model is used to verify that data was delivered without error?

Data Link

Which layer of the OSI model includes VLANs?

Session

Which layer of the OSI model is used to create a connection so that a host can transfer files?

Well Known Ports

Which port categories include inbound ports of HTTP, HTTPS, FTP, and DNS?

UDP

Which protocol do you use as the transport protocol for a video application?

Address Resolution Protocol (ARP)

Which protocol is used to translate IP addresses to MAC addresses?

Netstat -an

(Shows TCP and UDP connections numerically.

HTTP

Almost all of your users connect to Web sites with Internet Explorer. they usually type domain names such as www.microsoft.com. What protocol is initiated by default when they press Enter after typing the domain name?

Encapsulated

As you delve into a packet of data with your protocol analyzer, you notice that the frame size is bigger than the packet size. This is because the packet is ___________ inside the frame.

Three

How many layers are incorporated in the OSI model communications subnetwork?

Four

How many layers does the TCP/IP model have?

Netstat Command

Shows basic connections.

Netstat -a

Shows in depth TCP and UDP connections.

Protocol Stack

Sometimes a protocol suite such as TCP/IP is referred to as a _____________.

Ethernet

The IT director asks you to connect a client computer to an 802.3ab network. This network uses the __________ standard.

Internet Engineering Task Force (IETF)

The TCP/IP model is maintained by the __________.

Protocol Analyzer

You have been instructed to capture and analyze packets on a server. What tool will allow you to do this?

Netstat -an

You need to find out the Internet connections a particular computer has made in the recent past. You also need to see numeric information so that you know the IP address and port numbers of the destination computers. You should type the ___________ in the command prompt.

Ipconfig/all

You need to find out the MAC address of your director's computer. He has given you permission to access his computer. You access the command prompt. What command should you type to see the computer's MAC address?

Arp -a

You need to find out the MAC addresses of all the computers that a particular user's computer has connected to in the recent past. What command should you use to accomplish this?

Network

You need to install a router on your company's network that will allow access to the Internet. What layer of the OSI does this device reside on?

Layer 4 (Transport Layer)

You run a netstat -an command in the command prompt and notice many connections being made that say TCP in the left-most column. What layer of the OSI is TCP referring to?

Layer 2 (Data Link Layer)

You suspect a problem with your computer's network adapter and its ability to send the correct frames of data that correspond with the network architecture used by the rest of your computers. What layer should you attempt to use as a troubleshooting starting point?

53

Your company hosts a DNS server that resolves domain names to IP addresses. This server must have port ___________ open to service those requests for name resolutions.

80 & 443

Your manager wants you to allow HTTP and HTTPS connections to the company web server. In order to do this , you need to open inbound ports __________ and ___________.

Media Access Control (MAC) address

a unique identifier assigned to network adapters by the manufacturer. This address is six octets in length and is written in hexadecimal.

Layer 3 Switch

determines paths for data using logical addressing (IP addresses) instead of physical addressing (MAC addresses).

Open Systems Interconnection (OSI)

helps network engineers, network administrators, and systems engineers define how data networking actually works from one computer to another, regardless of where the computer is or what software it runs.

Physical Layer

includes but is not limited to cables, jacks, patch panels, punch blocks, hubs, and MAUs.

Address Resolution Protocol/ARP Table

layer 3 protocol that resolves or translates IP addresses to MAC addresses, allowing connectivity between the layer 3 IP system and the layer 2 Ethernet system.

Internet Control Message Protocol (ICMP)

ping utilizes this to send test packets to other computers; this is also a network layer protocol.

Content Addressable Memory or (CAM) Table

switches have memory that is set aside to store the MAC address to port translation table, known as the ___________.

Communications Subnetwork

the guts of OSI model transmissions, consisting of layers 1 through 3. Regardless of what type of data transmission occurs in a computer network, the ____________ will be employed.

Layer 2 Switch

the most common type of switch used on a LAN.

Segments/Messages

the unit of measurement used in the Transport Layer.

Frames

the unit of measurement used on the Data link layer.

Packets

the unit of measurements used on the Network Layer.

Port Range 49,152-65,535

these ports can be used by applications, but they cannot be registered by vendors. Dynamic and private ports.

Transport Layer

this layer ensures error-free transmission between hosts through logical addressing. Therefore, it manages the transmission of messages through layers 1 through 3.

Data link layer (DLL)

this layer establishes, maintains, and decides how transfer is accomplished over the physical layer.

Network layer

this layer is dedicated to routing and switching information to different networks, LANs, or internetworks.

Application Layer

this layer is where message creation-and, therefore packet creation begins. DB access is on this level. End-user protocols such as FTP, SMTP, Telnet, and RAS work at this layer.

Presentation Layer

this layer translates the data format from sender to receiver in the various OSes that may be used.

Content Addressable Memory or (CAM) Table

this table can be compromised with a MAC Flood attack.

NetBios (Network Basic Input Output System)

this works on the Session Layer of the computer.

Bits

unit of measurement used on the Physical Layer.