Ch. 5 - Network and Transport Layers
Routers consist of :
1.) CPU 2.) Memory 3.) Ports/interfaces
3 ways to connect to a router:
1.) Console port (Management Port) 2.) Network Interface Port 3.) Auxiliary Port
3 Main functions of a Router
1.) Determines a path for a packet to travel over 2.) Transmits the packet across the path 3.) Supports communication between a wide variety of devices and protocols.
Two Drawbacks to dynamic routing:
1.) It requires more processing by each computer or router in the network than does centralized routing or static routing. Computer resources are devoted to adjusting routing tables rather than sending messages. 2.) The transmission of routing information 'wastes' network capacity.
4 pieces of network layer addressing and routing information needed when a computer is installed on a TCP/IP network.
1.) Its IP address 2.) A subnet mask 3.) IP address of the DNS Server 4.) IP address of an IP gateway( router) leading outside the subnet.
3 Functions of the Transport Layer (layer 4)
1.) Linking the application layer to the network 2.) Segmenting 3.) Session Management
2 Functions of the network layer (layer 3)
1.) Routing 2.) Addressing
Session
A conversation between two computers
Address Resolution Protocol (ARP)
A formatted broadcast message to find out the data link layer address of computers in that subnet
Dynamic Addressing
A server is designated to supply a network layer address to a computer each time the computer connects to the network
multicasting
Addresses from 224 to 239 belong to class D and are reserved for _____
reserved addresses
Addresses starting from 224 are ____ that should not be used on IP networks.
broadcast messages
Addresses starting with 255 are reserved for _____
Autonomous System
An ____ is simply a network operated by one organization or an organization that runs one part of the internet.
subnet mask
Any portion of the IP address can be designated as a subnet by using a ____. Every computer is given one to determine if they are the same subnet
Internet Group Management Protocol (IGMP)
Computers wishing to participate in a multicast send a message to the sending computer or some other computer performing routing along the way using a special type of packet called a ____.
Decentralized
Each computer is responsible for knowing all addresses
interface
Each connection in regards to routing is called a _____
Connection-Oriented Messaging
Establishing a session and transmitting till the conversation is done and then ending the session
4.2 b illion
IPv4 has a max of ____ addresses
primary reason for increase in packet size
IPv6 address size increased from 32 to 128 bit
3.4 x 10 ^38
IPv6 max addresses is ___
16 byte
IPv6 uses a ____ long address
TCP/IP
Most commonly used set of transport and network layer protocols. Worlds most popular protocol set
Packets
Network layer PDUs are called _____
Centralized
One computer knows all addresses
Unicast Message
One computer sends a message to another computer. The most common type of message in a network.
exterior routing protocols
Protocols used between autonomous systems are called _____.
Dynamic Routing (adaptive routing)
Routing decisions are made in a decentralized manner by individual computers
Connectionless Messaging
Sending one quick message, and not starting a session
loopback
The 127 address range is reserved for a computer to communicate with itself and is called a _____
IP protocol
The ____ defines the address space that can be used on the Internet.
Physical address or MAC address
The data link layer address is called the _____ or ____
Dynamic Host Configuration Protocol (DHCP)
The most common standard for dynamic addressing is _____.
data link layer address
The network layer identifies the _______ of the next computer to which the message is sent
Cisco Internetwork Operating System (IOS)
The operating system used in 90% of routers. Uses a command line interface rather than a graphical user interface.
interior routing protocols
The routing protocols used inside an autonomous system are called ____.
Centralized, Static and Dynamic
Three Fundamental approaches to routing
Class A, B and C
Three classes of addresses that can be assigned to organizations
How do you establish a connection?
To establish a connection, the transport layer on both ends must send a SYN and receive an ACK
Address Resolution
Translating the application layer address of the destination into a network layer address and then to a data link layer address process is called ____
Segment
Transport layer PDU is called a _____
TCP.....UDP
When connection-oriented messaging is desired, ___ is used. When connectionless messaging is desired, ____ is used.
classes of service
With QoS (quality of service), different _____ are defined, each with different priorities.
port address
With TCP/IP, each application layer software package has a unique _____
Link State Dynamic Routing
With ____, computers or routers track the number of hops in the route, the speed of the circuits in each route, and how busy each route is.
Distance Vector Dynamic Routing
With ____, routers count the number of hops along a route. A hop is one circuit.
Routers
___ are usually found ate the edge of subnets because they are the devices that connect subnets together and enable messages to flow from one subnet to the other
Resource Reservation Protocol (RSVP) and Real Time Streaming Protocol (RTSP)
____ and ____ both permit application layer software to request connections that have certain minimum data transfer capabilities.
Routers
____ connect two or more subnets so they have a separate address on each subnet. Without them, the two subnets can't communicte.
Border Gateway Protocol (BGP)
____ is a dynamic distance vector exterior routing protocol used on the Internet to exchange routing information between autonomous systems - that is, large sections of the Internet. Large, complex, and often hard to administer.
Routing Information Protocol (RIP)
____ is a dynamic distance vector interior routing protocol that is commonly used in smaller networks, such as those operated by one organization.
Enhanced Interior Gateway Routing Protocol (EIGRP)
____ is a dynamic hybrid interior routing protocol developed by Cisco and is commonly used inside organizations. Has some features that act like distance vector and some that act like link state protocols. Improved version of IGRP.
Static Routing
____ is decentralized, all computers or routers in the network make their own routing decisions following a formal routing protocol
ICANN (Internet Corporation for assigned Names and Number)
____ is responsible for managing the assignemnt of network layer addresses and application layer addresses. They set the rules by whcih new domain names are created and IP addresses assigned. Manages a set of internet domains and authorizes private companies to become domain name registrars.
Internet Control Message Protocol (ICMP)
____ is the simplest interior routing protocol on the Internet.
Server name resolution
____ is the translation of application layer addresses into network addresses . Done using Domain Name Service(DNS).
User Datagram Protocol (UDP)
____ is used when a sender needs to send a single small packet to the receiver
Connectionless Messaging
____ means each packet is treated separately and makes its own way through the network
Access Control List (ACL)
____ plays an important role in network security. It defines what types of packets should be routed what types should be discarded.
Connection-Oriented Messaging
____ sets up a TCP connection(session) between the sender and receiver.
TCP/IP
____ was developed for US Department of Defense's ARPANET by Vinton Cerf and Bob Kahn in 1974
Open Shortest Path First (OSPF)
_____ is a dynamic hybrid interior routing protocol that is commonly used on the internet. More efficient than RIP, because it doesn't use broadcast messages.
Intermediate System to Intermediate System (IS-IS)
_____ is a link state interior routing protocol that is commonly used in large networks. ISO protocol that has been added to many TCP/IP networks.
Application layer address
_____ is also called a server name
Port address of 80
_____ is called the well-known port
Segmenting
_____ is taking one outgoing message from the application layer and break ingit into a set of smaller segments for transmisson
Routing
_____ is the process of determining the route or path through the network that a message will travel from the sending to the receiving computer
Quality of Service
_____ routing i a special type of connection-oriented messaging in which different connections are assigned different priorities.
Classless addressing (slash notation)
_____ uses a slash to indicate the address range. Also called slash notation.
Connectionless Messaging
______ is most commonly used when the application data or message can fit into one single message.
Multicasting
______ is sending messages to a group of computers rather than just one computer or to every computer (broadcast)
Centralized Routing
all routing decisions are made by one central computer or router. Commonly used in host based networks .
byte
octet means ___
User Datagram Protocol (UDP)
second type of transport layer protocol