ISM Data Networks and Security Ch.1 Review (edited)

When a packet travels through an internet, are there usually more data links or routes along the way?

There are usually more data links since they travel through single networks.

A Single Network

A network that uses a single set of standards for all devices. They are incompatible.

DNS (Domain Name System) - 5 Steps + Definition

A server that provides IOP addresses for users who know only a target host's host name. 1) Originating host wants to send packets to fsu.edu 2) Originating host sends DNS request message to the DNS server. The message gives the target host's host name and asks for its IP address 3) The DNS host looks up fsu.edu in its DNS table (lists the IP address for fsu.edu) 4) DNS server sends back a DNS response message to the originating host 5) The originating host can send packets to fsu.edu by addressing them to the IP address (no longer needs DNS)

Point-to-Point Network

- the simplest network topology - there is a dedicated link between two resources - not often used because it limits how devices can communicate with each other - example would be a connection between the monitor and the motherboard within a computer

When a packet is transmitted from a source host to a destination host separated by four single networks, how many packets will there be? How many frames?

1 packet 4 frames A packet is carried inside of a frame.

What are the three defining characteristics of single networks?

1) Point-to-Point Network 2) Ethernet 3) Frames & Packets

Please complete the decimal to binary conversion: 10 in decimal is _____________ in binary (0s and 1s).

1010 10/2 = 5 R0 5/2 = 2 R1 2/2 = 1 R0 1/2 = 0 R1

How long is an EUI-48 address?

48 bits

For data links in a single network, what is a message called?

A message in a single network is a frame

What is multiplexing?

Combining multiple signals for transmission over a single transmission path.

DHCP (Dynamic Host Configuration Protocol) - 5 Steps + Definition

DHCP = How client host gets an IP address 1) Client boots up and realizes doesn't have an IP address 2) Client broadcasts DHCP Request (broadcasts because client doesn't know IP of local DHCP server) 3) Server finds available IP addresses in database 4) Server sends DHCP response to client with IP ---For subsequent packets sent by client, this is the packet's source IP = Dynamic IP Address 5) When client shuts down, it forgets IP address (process restarts on boot up=new IP)

At what layer do you find EUI-addresses?

Data Link Layer (Layer 2 in OSI)

Data link vs route

Data links are the individual pathways that data travels through along its way whereas routes are the entire pathways that data is transmitted through. Data links are the path between routers and routes are the pathway between destination and source host.

What is the most widely used single-network address? What else is it called?

EUI-48 = MAC Address

Switched network standard

Ethernet

What does EUI stand for?

Extended Unique Identifier

How does fragmentation reduce transmission cost through multiplexing?

Fragmentation fills transmission lines with messages more efficiently and multiplexing allows the packets of many conversations to share transmission lines, which reduces the cost.

What is fragmentation?

Fragmentation is the storing of a file in separate areas of memory because they are too large to fit in a single IP packet. It is part of the transport process that fragments the application into several fragments, placing each in a separate TCP segment, which is placed in its own IP packet.

What do data link layer (DLL) standards govern?

Frames and switch operation -How the frame is organized, and how switches, access points, and other single network forwarding devices forward frames.

What is HTTP?

HyperText Transfer Protocol - the protocol used for transmitting web pages over the Internet --Standard for browser-webserver

How does fragmentation improve error handling?

If there is a transmission error, only a single frame or packet is resent—not the entire applications message, which can be very long.

What is an ISP? What is their role?

Internet Service Provider ISPs sell access to the internet for personal and company use. ISP's allows users to connect to networks that contain all the necessary tools and equipment that allow for internet connection to be established.

At what layer do you find wired connections?

Layer 1 - Physical

At what layer do you find Switches?

Layer 2

At what layer do you find EUI-48 addresses?

Layer 2 - Data Link

At what layer do you find frames?

Layer 2 - Data Link

At what layer do you find IP addresses?

Layer 3

At which layer do you find routers?

Layer 3

At what layer do you find packets?

Layer 3 (internet)

At which layers are standards defined for a single-network?

Layers 1 and 2

Edward Joseph Snowden (born June 21, 1983) revealed numerous global surveillance programs -_______ , many run by the NSA (National Security Agency) and the Five Eyes Intelligence Alliance with the cooperation of telecommunication companies and European governments, and prompted a cultural discussion about national security and individual privacy.

PRISM - Planning Tool for Resource Integration, Synchronization, and Management

IP header contains both ________ and ___________.

Source IP address and Destination IP address (IP of sender and receiver)

What governs how a frame is organized?

The data link standard = Point-to-Point Protocol (PPP)

Physical Links VS Data links VS routes

The difference between a physical link and a data link is that a physical link needs to be directly connected to be able to transmit data whereas a data link uses a wireless connection and can travel farther without the need of a physical standard. A physical link is different from a route as a route is the overall path a packet goes through to reach its destination host. A physical link is simply the direct and physical connection usually through a connector on each device

Physical standard (point-to-point networks). What three things does it cover?

The direct physical connection standard for point-to-point networks. 1) The transmission medium (optical fiber, radio transmission 2) A Physical connector on each device 3) How 1s and 0s are transmitted over this physical link

What is the name and number of the lowest network standards layer?

The physical layer (1)

Why is layering important?

There can be changes made to individual layers without affecting the whole process. Each layer functions individually before functioning as a group

IPv6 addresses are ________ bits long. a) 128 b) 64 c) 24 d) none of the above e) 32

a) 128

An IP packet may include a(n) ________. a) application message or fragment AND TCP segment or UDP datagram b) application message or fragment c) TCP segment or UDP datagram d) None of them are correct.

a) application message or fragment AND TCP segment or UDP datagram

The IETF primarily ________. a) creates Internet standards b) all are correct. c) manages the Internet d) coordinates the work of ISPs

a) creates Internet standards

If there are 10 routers between the source and destination hosts, how many transport processes will be involved on all devices? a) 10 b) 2 c) 1 d) 12

b) 2 --Transport Process = End-to-End (Host-to-Host)

In a single switched network, a ________ connects consecutive switches. a) data link b) physical link c) route d) none of them are correct

b) physical link A physical link connects consecutive switches in a SINGLE switched network

Most servers are ________. a) mainframes b) rack servers c) routers d) Windows PCs

b) rack servers

The KrebsOnSecurity.com attack ________. a) used IoT devices to attack the site b) was a denial of service attack and used IoT devices to attack the site c) neither of above was right. d) was a denial of service attack.

b) was a denial of service attack and used IoT devices to attack the site

On the Internet, a ________ host usually gets a dynamic IP address. a) server b)client c) both client and server d) neither client nor server

b)client Client = Dynamic IP Server = Static IP ---Stable to avoid constant IP change (easier for DNS)

Paths across a single network are called ________. a) none are correct b) routes c) data links d) physical links

c) data links

Source and destination EUI-48 addresses are found in ________ headers. a) IP b) UDP c) frame d) TCP

c) frame Source and destination EUI-48 (Extended Unique Identifier-48) addresses are found in frame headers --Ethernet frames are delivered to Ethernet addresses. The source and destination Ethernet addresses are placed in the frame header. --Ethernet data link addresses follow the EUI-48 Standard

If a host cannot reach a DNS server, it ________. a) will have to rely on host names b) cannot have a host name c) is unlikely to be able to communicate with most server hosts d) will need to use a DHCP server

c) is unlikely to be able to communicate with most server hosts

The network stack implements the ________ layer process. a) application b) physical c) data link d) transport

d) transport

What process adds a header in front of an application message or fragment? a) internet b) application c) data link d) transport

d) transport For short application messages, the Transport Process in the network adds a short Transmission Control Protocol (TCP) header to create a TCP Segment

IPv4 addresses are ________ bits long. a) 128 b) 64 c) 24 d) none of the above e) 32

e) 32

What is a route?

the path a packet takes from the source host to the destination host across an internet