Chapter 1 Cisco

Identity theft

An attack to steal the login credentials of a user in order to access private data.

Data interception and theft

an attack to capture private information from an organization's network

Examples of Extranet

-A company providing access to outside suppliers/contractors -A hospital providing a booking system to doctors so they can make appointments for their patients -A local office of education providing budget and personnel information to the schools in its district

There are two other terms which are similar to the term Internet

-Intranet -Extranet

The two most common types of network infrastructures

-Local Area Network -Wide Area Network

Examples of Media

-Metallic wires within cables -Glass or plastic fibers (fiber optic cable) -Wireless transmission

Cloud computing offers the following benefits:

-Organizational flexibility- Users can access the information anytime and anyplace using a web browser -Agility and rapid deployment- IT department can focus on delivering the tools to mine, analyze, and share information and knowledge from databases, files, and people. -Reduced cost of infrastructure- Technology is moved from on-site to a cloud provider, eliminating the cost of hardware and applications -Refocus of IT resources- Cost savings of hardware and applications can be applied elsewhere. -Creation of new business models- Applications and resources are easily accessible, so companies can react quickly to customers needs.

Processes running on the intermediary network devices perform these functions

-Regenerate and re-transmit data signals -Maintain information about what pathways exist through the network and internet work -Notify other devices of errors and communication failures -Direct data along alternate pathways when there is a link failure -Classify and direct messages according to QoS (quality of service) priorities -Permit or deny the flow of data, based on security settings

Network infrastructure can vary greatly in terms of:

-Size of the area covered. -Number of users connected -Number and types of services available.

Criteria for choosing network media are:

-The distance the media can successfully carry a signal. -The environment in which the media is to be installed. -The cost of the media and installation.

Networking Interface Card (NIC)

A NIC, or LAN adapter, provides the pysical connections to the network at the PC or other host device. The media connecting the PC to the networking device plugs directly into the NIC.

Physical Port

A connector or outlet on a networking device where the media is connected to a host or other networking device.

Storage Area Network (SAN)

A network infrastructure designed to support file servers and provide data storage, retrieval, and replication. It involves high-end servers, multiple disk arrays (called blocks), and fibre channel interconnection technology.

Wide Area Network (WAN)

A network infrastructure that provides access to other networks over a wide geographical area. -WANs interconnect LANs over wide geographical area such as between cities, states, provinces, countries, or continents -WANs are usually administered by multiple service providers. -WANs typically provide slower speed links between LANs.

Local Area Network (LAN)

A network infrastructure that provides access to users and end devices in a small geographical area. -Provide high speed bandwidth to internal end devices and intermediary devices. -A LAN is usually administered by a single organization or individual -LANs interconnect end devices in a limited area such as a home, school, office building, or campus

Metropolitan Area Network (MAN)

A network infrastructure that spans a physical area larger than a LAN but smaller than a WAN (e.g a city). MANs are typically operated by a single entity such as a large organization

Scalability

Additional users and whole networks can be connected to the Internet without degrading performance for existing users

Security

Administrators can protect the network with software and hardware security and by preventing physical access to networks devices.

Hackers attacks

An attack by a knowledgeable person to user devices or network resources

Zero hour attacks

An attack that occurs on the first day that a vulnerability becomes known

Dial-up Telephone

An inexpensive option that uses any phone line and a modem. To connect to the ISP, a user calls the ISP access phone number.

Extranet

An organization may use an extranet to provide secure and safe access to individuals who work for a different organizations but require company data.

End device

Can act as a client, a server, or both

Host

Can send and receive messages on the network.

Cellular

Cellular Internet access uses a cell phone network to connect. Performance will be limited by the capabilities of the phone and the cell tower to which it is connected.

Some examples of end devices are

Computers (workstations, laptops, file servers, web servers) VoIP phones Telepresence endpoint Mobile handheld

The network infrastructure contains three categories of network components

Devices Media Services

The advantages of peer-to-peer networking

Easy to setup Less complexity Lower cost since network devices and dedicated servers may not be required Can be used for simple task such as transferring files and sharing printers.

Logical topology diagram

Identify devices, ports, and IP addressing scheme

Physical topology diagram

Identify the physical location of intermediary devices, configured ports, and cable installation

What do Intermediary devices do

Intermediary devices determine the path that the message should take through the network

IoE

IoE (internet of everything) is bringing together people, process, data, and things to make networked connections more relevant and valuable.

Cloud Computing

Is the use of computing resources (hardware and software) that are delivered as a service over a network. The term "cloud computing" really refers to web-based computing, Online banking, online retail stores, and online music downloading.

Circuit-switched Connection-Oriented-Networks

Many circuit-switched networks give priority to existing circuit connections at the expense of new circuit request.

Examples of intermediary network devices are

Network access (switches and wireless access points) Internet working (routers) Security (Firewalls)

The disadvantages of peer-to-peer networking

No centralized administration Not as secure Not scalable All devices may act as both clients and servers which can slow down their performance.

DSL

Provides high bandwidth always on, connection to the Internet. It requires a special high-speed modem that separates the DSL signal from the telephone signal and provides an Ethernet connection to a host computer

Quality of Service (QoS)

Quality of Service, managed by the router, ensures that priorities are matched with type of communication and its importance to the organization. Web pages usually receive lower priorities, and streaming media receives higher priorities.

Fault tolerance

Redundant connection allow for alternative paths if a device or a link fails. The user experience is unaffected.

Satellite

Satellite service is a good option for homes or offices that do not have access to DSL or cable. Satellite dishes require a clear line of sight to the satellite.

Wireless LAN (WLAN)

Similar to a LAN but wirelessly interconnects users and end points in a small geographical area

Spyware, and Adware

Software installed on a user device that secretly collects information about the user

Interface

Specialized ports on an internet working device that connects to individual networks. Because routers are used to interconnect networks, the ports on a router are referred to network interfaces.

Metallic wires

The data is encoded into electrical impulses

Access control list (ACL)

To further filter access and traffic forwarding

Intrusion prevention system (IPS)

To identify fast-spreading threats, such as zero-day or zero-hour attacks

Virtual private network (VPN)

To provide secure access to remote workers

Wireless

Transmission patterns of electromagnetic waves depict the various bit values.

Fiber optic

Transmissions rely on pulses of light, or infrared

Cable

Typically offered by cable television service providers. It provides high bandwidth, always on, connection to the internet

The most common threats to networks include:

Viruses, worms, Trojan horses, spyware, adware, hacker attacks, denial of service, data interception,

Converged Network

are capable of delivering voice, video streams, text, and graphics between many different types of devices over the same communication channel and network structure.

Denial of Service attacks

attacks designed to slow or crash application and processes on a network device

Intranet

is a term often used to refer to a private connection of LANs and WANs that belong to an organization, and is designed to be accessible only by the organization's members, employees, or other with authorization

Wireless Internet Service Provider (WISP)

is an ISP that connects subscribers to a designated access point or hot spot using similar wireless technologies in home (WLAN). WISP are more commonly fond in rural environments.

Viruses, worms, and Trojan horses

malicious software and arbitrary code running on a user device.

Firewall Filtering

to block unauthorized access to the network

Antivirus and antispyware

to protect user devices from malicious software

Dedicated firewall systems

to provide more advanced firewall capability, that can filter large amounts of traffic with more granularity