ITEC51 (Sir Anda) Flashcards
are networking hardware used to connect one
network device to other network devices or to connect two or more
computers to share printers, scanners etc.
Networking cables
these cables are essentially the carrier or media through which data
flows. Twisted pair cable is used in many ethernet networks.
Networking cables
the most common network cabling
unshielded twisted pair (UTP).
Types of Network Cable
Coaxial Cable
Fiber Optic Cable
Twisted Pair Cable
is another type of copper cable which has an inner conductor
surrounded by foam insulation, symmetrically wrapped by a woven braided
metal shield, then covered by in a plastic jacket.
this unique design allows coaxial cable runs to installed next to metal
objects such as gutters without the power losses that occur in other types of
transmission lines.
this kind of cable is mainly adopted in feedlines connecting radio
transmitters and receivers with their antennas, computer network
connections, and distributing cable television signals.
Coaxial Cable
cable consists of a bundle of glass threads, each of which is capable
of transmitting messages modulated onto light waves.
has a complicated design and structure. This type of cable has an
outer optical casing that surrounds the light and traps it within a
central core.
the inside of the cable (the core) must configured in two different
ways – Single-mode and multi-mode; although the difference may
seem small, it makes a tremendous difference to the performance and
the usage of fiber optic cables.
Fiber Optic Cable
cable is a type of ordinary wiring which connects home and many business
computers to the telephone company.
is made by putting two separate insulated wires together in a twisted
pattern and running them parallel to each other, which helps to reduce
crosstalk or electromagnetic induction between pairs of wires.
Twisted Pair Cable
two common types of twisted pair cables:
shielded twisted pair (STP) cable
unshielded twisted pair (UTP) cable.
is available for Token Ring networks,
STP shielded twisted pair
is more suitable for Ethernet networks.
UTP unshielded twisted pair
used to connect computing devices together directly.
used to connect to PCs directly together, also used for
connecting networking devices together like Switch to Switch
etc.
Cross-over (T568A )
refers to cables that have the pin assignments on each end of
the cable. In other words, Pin 1 connector A goes to Pin 1 on
connector B, Pin 2 to Pin 2, etc.
are most commonly used to connect a host to a client.
are primarily used for connecting unlike devices.
Straight Through(T568B )
have opposite Pin assignments on each end of the cable
sometimes referred to as Yost cables are most commonly used to
connect to a device’s console port to make programming changes
to the device. Unlike crossover and straight-wired cables, rollover
cables are not intended to carry data but instead create an interface
with the device.
Roll over
is a large network of information that is not tied to a single location
can facilitate communication, the sharing of information and much more between devices from around the world through a WAN provider
operates beyond the geographic scope of a LAN
Wide Area Network (WAN)
are telecommunications services provided by telecommunications and long-distances carriers that route packets of data between LAN in diverse geographical locations to form a WAN
Packet Switch Services
is a telecommunications service provided to businesses by telecommunications and long-distance carriers
is an umbrella term describing any service that provides switched connections between a consumer and a provider
Circuit Switch Services
is associated with Asynchronous Transmission Mode (ATM) which is considered to be a high speed switching technology that attempted to overcome the speed problems faced by the shared media like Ethernet and FDDI
uses a connection-oriented packet-switched network
Cell Switch Services
this methodology uses a fixed length of packets of 53 bytes out of which 5 bytes are reserved for header
breaks the information into smaller packets of fixed length and thereby ensuring guaranteed delays
Cell Switch Services
is done through the Public Switched Telephone Network (PTSN), which is composed of multiple telephone carriers from around the world
can be used access the Internet by connecting a computer to a computer to a modem, connecting the modem to an analog phone line, and dialing in to a service provider
Dial-up modems
is an always-on internet access method available in areas that have digital cable television
connectivity is achieved by using a device called a cable modem. it has a coaxial connection for connecting to the provider’s outlet and an unshielded twisted pair (UTP) connection for connecting directly to a system or to a hub, switch, or router
Cable modems
Other WAN services
Dial-up modems
Cable modems
guide and direct network data, using packets that contain various kinds of data such as files, communications, and simple transmission like web interactions.
are responsible for receiving, analyzing, and forwarding data packets among the connected computer networks. When a data packet arrives, the router inspects the inspects the destination address, consults its routing tables to decide the optimal route and then transfers the packet along this route
Routers
common router manufacturers:
cisco
D-link
HP
3Com
Juniper
Asus
TP-Link
Huawei
LinkSys
Nortel
Types of Routers
Wireless Router
Broadband Router
Core Router
Edge Router
Virtual Router
They provide WiFi connection WiFi devices like laptops, smartphones.
They can also provide standard Ethernet routing. For indoor connections, the range is 150 feet while its 300 feet for outdoor connections
Wireless Router
They are used to connect to the internet through telephone and to use voice over Internet Protocol (VoIP) technology for providing high-speed internet access. They are configured and provided by the Internet Service Provider (ISP)
Broadband Router
They can route data packets within a given network, but cannot route the packets between the networks. They helps to link all devices within a network thus forming the backbone of network. It is used by ISP and communication interfaces.
Core Router
are specialized routers that act as gateways at the network edge
they enable connectivity between an enterprise network and an external network
Edge Router
are pieces of software that allow some router functions to be virtualized in the cloud and delivered as a service
these routers are ideal for large businesses with complex network needs. They offer flexibility, easy scalability, and a lower entry cost.
Virtual Router
WAN Topologies
Point to point topology
Ring topology
Hub and Spoke topology
Mesh topology
Tiered topology
Hybrid topology
employs a point-to-point circuit between two endpoints
provides a Layer 2 transport service through the service provider network.
packets sent from one site are delivered to the other site and vice versa.
is transparent to the customer network, as if there was a direct physical link between two endpoints
Point to point topology
a ring-shaped WAN constructed with point-to-point transmission facilities can be used to interconnect a small number of sites and provide route redundancy at a potentially minimal incremental cost
can use dynamic routing protocols
Ring topology
if a private network connection between multiple sites is required, a point-to-point topology with multiple point-to-point circuits is one option.
This interface can be expensive. A less expensive option is a point-to-multipoint topology
spokes sites are connected to each other via Hub sites
the network communication between two spokes always travel through the hub
Hub and Spoke topology
any sites can communicate directly with any other sites
is highly redundant
is the most desirable WAN topology
Mesh topology
is a modified version of the basic hub and spoke topology
constructed with dedicated facilities offers improved fault tolerance over the simple star topology without comprising scalability
Tiered topology
is useful in larger, more complex networks
may be developed in a multitiered WAN by using a fully meshed topology for the backbone nodes only.
Hybrid topology
Router Components
Input ports
Routing processor
it performs the physical layer functionality of terminating an incoming physical link to a router
it performs the data link layer functionality needed to interoperate with the data link layer functionality on the other side of the incoming link
it also performs a lookup and forwarding function so that a datagram forwarded into the the switching fabric of the router emerges at he appropriate output port
Input ports
computes the forwarding table, implements routing protocols, and runs the software to configure and manage the router
it also handles any packet whose destination address cannot be found in the forwarding table in the line card
Routing processor
connects the router’s input ports to its output ports
is completely contained with the router - a network inside of a network router
Switching Fabrics
3 Switching Fabrics
Switching Via a Memory
Switching Via a Bus
Switching Via a Crossbar
Router Modes
User Execution Mode
Privileged Mode
Global Configuration Mode
Interface Configuration Mode
ROMMON Mode
is the first mode a user has access to after logging into the router.
this mode allows the user to execute only the basic commands
User Execution Mode
allows users to view the system configuration, restart the system, and enter router configuration mode.
#
Privileged mode
we type configure terminal to the user mode
commands enter in these modes are called global commands and they affect the running-configuration of the router
different configuration like making local database on router by providing username and password
Global Configuration Mode
in this mode, only configuration of interfaces are done.
assigning an IP address to an interface, bringing up the interface are the common tasks done in this mode
Interface Configuration Mode
stands for ROM monitor
we can enter in this mode when we interrupt boot process of the router. Generally, we enter in this mode while password recovery process or Backing up of IOS on device like TFTP server
it is like BIOS mode of a PC. / bootstrap
ROMMON Mode
the unique number of ID assigned to one host or interface in a network
Address
a portion of a network that shares a particular subnet address
Subnet
a 32-bit combination used to describe which portion of an address refers to the subnet and which part refers to the host
Subnet Mask
a network connection
Interface
Helps you know which portion of the address identifies the network and which portion of the address identifies the host.
Network Mask
was introduced in order to improve both address space utilization and routing scalability in the internet
it was needed because of the rapid growth of the internet and growth of the IP Routing tables held in the internet routers
CIDR (Classless Interdomain Routing)
is an interactive CLI mode that prompts you for information needed to build an initial configuration for a cisco networking device.
provides help text at each prompt.
System Configuration Dialog
this command verifies that the interfaces are operating correctly and that they and the line protocol are in the correct state: up or down
show interfaces
this command displays a summary status of the interfaces configured for IP
show ip interface brief
this command verifies that the correct hostname and password were configured
show configuration
is a distributed database in which you can map hostnames to IP address through the DNS protocol from a DNS server
Domain Name System (DNS)
to keep track of domain names
refers to the server component of the domain name system, one of the two principal namespaces of the internet
Name servers
to speed the process of converting names to addresses, the name server maintain a database
stores the results from previous responses
Cache
are widely used in networks in today
can be used to define an exit point from a router when no other routes are available or necessary
Static Routing
can manually configure a static route to reach a specific network
network administrator
can be used to define an exit point from a router when no other routes are available or necessary
default route
help the network administrator manage the time consuming and exacting process of configuring and maintaining static routes
they are scalable and automatically determine better routes if there is a change in the topology
Dynamic Routing
is a collection of routers under a common administration such as a company or an organization.
also known as a routing domain
Autonomous System (AS)
used for routing within an AS.
companies, organization, and even service providers uses this on their internal networks
Interior Gateway Protocols (IGP)
used for routing between autonomous systems
Exterior Gateway Protocols
is the only currently viable EGP and is the official routing protocol used by the internet
Border gateway protocol
identifies how far it is to the destination network and is based on a metric such as the hop count, cost, bandwidth, delay, and more.
Distance
specifies the direction of the next-hop router or exit interface to reach the destination
Vector
First generation legacy protocol
RIPv1
Simple distance vector routing protocol
RIPv2
First generation cisco proprietary protocol
IGRP
advanced version of distance vector routing
EIGRP
Is performed by every switching node in the network
a complex routing protocol that shares information with other routers in order to determine the best path
Link-State Routing Protocols
Popular standards-based routing protocols
OSPF
Popular in provider networks
IS-IS
DO NOT send subnet mask information in their routing updates
Classful Routing Protocols
DO send subnet mask information in their routing updates
Classless Routing Protocols
