Quiz X - IP Addressing & Routing (Ch. 7-8, 13) - (CANCELLED Quiz 3) Flashcards
What is the origin of the term internet?
- A short form of the technical term internetwork
- the result of interconnecting computer networks
What is The Internet?
- A network of networks
- consists of millions of private, public, academic, business, and government networks
- local to global scope
- linked by a broad array of electronic, wireless and optical networking technologies
Does the Internet have a centralized governance?
- No, The Internet has no centralized governance in either technological implementation or policies for access and usage
Is there an overarching standard for the Internet?
- No, each constituent network sets its own standards
What body maintains IP address space and DNS definitions?
- ICANN
- Internet Corporation for Assigned Names and Numbers (ICANN)
- Only the overarching definitions of the Internet Protocol (IP) address space and the Domain Name System (DNS), are directed by a maintainer organization
What agency controls the technical standards of the internet?
- IETF
- The technical underpinning and standardization of the core protocols is an activity of the Internet Engineering Task Force (IETF),
- a non-profit organization of loosely affiliated international participants that anyone may associate with by contributing technical expertise.
How do you access the Internet?
you need an…
- Internet Service Provider (ISP) and an
- access line to your ISP
What does the ISP do?
Your ISP…
- gives you access and
- carries your packets
Do organizations also need to use an ISP?
- Yes, organizations also need ISPs
What comprises the Internet backbone?
- ISPs collectively comprise the Internet backbone
How do ISPs connect to each other?
- They interconnect at Network Access Points (NAPs)
How are ISPs classified?
- Tier-1 ISPs : national/international coverage
- Tier-2 ISPs : smaller, often regional coverage
- Tier-3 & Local ISPs : last hop (“access”) network (closest to end systems)
What are the relationships among different tiers of ISPs?
- Tier-2 ISP is customer of Tier-1 provider
- Local and Tier- 3 ISPs are customers of higher tier ISPs connecting them to rest of Internet
A data packet typically passes through only one network. True or False
- False, a packet passes through many networks!
How do the Network and Transport layers function in regard to the Internet?
[insert slide 9 image here]
How does the Network layer “create” the Internet?
- The network layer facilitates the interconnection of local networks establishing the Internet
What is TCP/IP?
- A set of protocols used for the Internet and other similar networks
What do TCP and IP stand for?
- TCP: Transmission Control Protocol
- IP: Internet Protocol
What types of networks does TCP/IP support?
- Supports both simple and complex networks
- Small LAN
- Multiple LANs interconnected into a WAN
What is the primary transmission responsibility of the Network layer?
- hop-by-hop
What is the primary transmission responsibility of the Transport layer?
- end-to-end
TCP operates on what OSI layer?
- TCP is the Transport layer protocol
IP operates on what OSI layer?
- IP is the Network layer protocol
When and where was TCP/IP created?
Created in the…
- 1970s at
- DARPA
Who created TCP/IP?
- Vint Cerf
- Bob Kahn
- (called “the fathers of the Internet”)
What is DARPA?
- Defense Advanced Research Projects Agency
What is an IP address?
- IP (Internet Protocol) address
- assigned to each device (e.g., computer, printer, router) participating in a computer network that uses the Internet Protocol
What versions of Internet Protocol are currently in use?
- IP Version 4: 32 bits
- IP Version 6: 128 bits
What is the length of an IPv4 address?
- 32 bits
What is the length of an IPv6 address?
- 128 bits
What is the maximum decimal number in an IPv4 address?
- 255
What is the format of IPv4?
- dotted decimal
- four decimal numbers separated by dots
- Each of the four parts represents a byte (8 bits)
Convert 129.174.1.38 into dotted decimal.
- 129.174.1.38 = 10000001.10101110.00000001.00100110
What is a static IP address?
- Manually type in all IP information (in the station)
- Every IP address must be unique
What is a dynamic IP address?
- Dynamically get address from a server using DHCP
- Automatically assigns an IP address whenever a computer connects to the network
What is the difference between static and dynamic addresses?
- static addresses do not change
- dynamic addresses are assigned when a host connects to the network
What does DHCP stand for?
- Dynamic Host Configuration Protocol
What is DHCP used for?
- Assigning IP addresses to hosts joining a network that need an IP address
How does DHCP work?
- Client requests IP address from DHCP server
- DHCP server provides address and other info
What is the difference between the network address and the physical address?
-
Physical address—refers to a particular device
- The physical address doesn’t change when the device is moved
-
Network address—refers only to the network in which the device resides
- The network address changes when the device is moved
How can a device be reached by using an IP address?
- To reach a device, there must be a mapping of its IP address to its physical address
What does ARP stand for?
- Address Resolution Protocol
What is ARP used for?
- ARP is used to
-
determine the MAC address of the destination computer
- based on its IP address
What are the steps in ARP?
- ARP broadcast by the originating router is used to determine the MAC address of the destination computer based on its IP address
- The destination computer replies with its MAC address
- The originating router records IP-Ethernet address pair in ARP cache and uses it to send future frames to the host without using ARP
What does ICMP stand for?
- Internet Control Message Protocol
What is ICMP?
- one of the core protocols of the Internet Protocol (IP) Suite
- chiefly used by the operating systems of networked computers to send error messages
- indicating, for example, that a requested service is not available or that a host or router could not be reached.
How are ICMP messages transmitted?
- ICMP messages are embedded in IP packets
- Type number—indicates kind of message problem
- Code number—specific details within type
What are subnets?
- logical networks with their own IP addresses
How are subnets created?
- created by assigning hosts to groups with their own subnet addresses
Routers are used within subnets to connect hosts
- No, hosts can physically reach each other without an intervening router