Lecture 6 (unfinished) Flashcards
What is the Internet?
Internet: Interconnected Network.
What is a switch?
Switch
o It is the central component of a single physical network (e.g Ethernet LAN)
o It interconnects computers in a physical network and transfers frames between them
What is a router?
• Router
o It Connects two or more networks and transmits the IP traffic between networks
o The networks can be heterogeneous => The format of the frames differ; (eg. Interface
Ethernet or 802.11)
Types of networks in internet
Backbone
metropolitan network
cosmopolitan network
local area network
What are backbones in terms of internet?
Backbones: Networks are used to interconnect other networks (e.g. WANs)
What are commercial networks in terms of internet?
Commercial networks provide access to their subscribers in backbone networks
What is ISOC?
It is a professional association that facilitates, promotes and supports the development of the Internet as a global communications system
What is ICANN
ICANN is responsible for the management of IP addresses and DNS domains
What is the Internet Architecture Board?
15 members
It serves as the final quality control council of Internet standards
What is IRFT?
IRFT deals with long-term research programs
What is IETF?
Internet Engineering Task Force
deals with the short-term creation of Internet standards
9 areas e.g. security
Layers in TCP-IP Protocol Stack
Application Transport Network Data Link Physical
Describe internet Protocol in terms of TCP-IP Layer?
Internet Protocol (IP)
o No guarantee if the packet will arrive
o Congestion may cause the routers due to limited buffer size
o When congested occurs, routers will drop the packets
What is an IP host?
IP host: A device with ΙΡ address
e.g. Ethernet switch (L3)
Multiple hosts can be located either on a network or part of a subnet
What are some IP layer Service Characteristics?
Connectionless service: There is no signaling establishment between sender and receiver
The IP Packet (Datagrams) vary in length
Best Effort Service
o Delay, out of sequence packets and manage losses from higher-layer protocols
o IP forwarding
o Using the routing tables
Provides reports for the transmission and delivery of IP Packet
o Using the protocol ICMP
What do IP packets/datagram consist of ?
A header followed by Payload
o Payload from higher-level protocols (eg. TCP, UDP)
Describe IP packets
IP packets are encapsulated within the physical network using a physical
network (e.g. Ethernet, WiFi)
Ethernet maximum length 1500 bytes
• Use of fragmentation and reassembly method for transmitting through
different networks maximum frame length
What is Forwarding in terms of IP Routing?
Forwarding: Transfer packets from router’s input to appropriate output
(interface)
What is Routing in terms of IP Routing
Routing: determine the route of packets from the sender to the recipient
Maximum Transmission Unit formula?
Maximum Transmission Unit
o MTU = IP Datagram (data + header)
What is multihoming in terms of IP Addressing?
Multihoming: When a host is connected to multiple networks and uses an IP address for each network
How are IP Addresses defined
IETF RFC standard 1166
