Networking Fundamentals

Ethernet Frame Sizes

• The minimum size of an Ethernet frame is 64 bytes.
• The maximum size of an Ethernet frame is 1518 bytes.

NVRAM on Cisco Devices

• NVRAM is a memory location on a Cisco router or switch.
• NVRAM stores the startup configuration file.

Subnet Masking

• An IP address of 10.1.100.50 with a subnet mask of 255.255.0.0 belongs to the 10.1.0.0 subnet
• An IP address of 10.1.100.50 with a subnet mask of 255.255.255.0 belongs to the 10.1.100.0 subnet.
• An IP address of 10.1.100.50 with a subnet mask of 255.0.0.0 belongs to the 10.0.0.0 subnet.

Types of Network Communication

• Broadcast communication sends a message to all devices on a local area network (one-to-all).
• Multicast communication sends a message to some group of devices on a local area network (one-to-group).
• Unicast communication sends a message to only one device on a local area network (one-to-one).

Multicast Messages

• Multicast messages are sent to a select group of hosts.

Encapsulation

• Encapsulation places one message inside another for transfer from source to destination.

OSI Model - Segmentation and Reassembly

• The transport layer of the OSI model defines services to segment and reassemble data for individual communications between end devices.
• Data is segmented and reassembled in the transport layer.

Network Scalability

• Scalability enables a network to quickly grow to support new users and applications.
• Scalability does not impact the performance of the service being delivered to existing users.

IPv4 Packet Header - Destination Address

• The destination address field in an IPv4 packet header typically stays the same during its transmission.

Runt Frames

• Runt frames are dropped by a Cisco Ethernet switch

IPv4 Address Representation

• The dotted decimal representation of the IPv4 address 11001011.00000000.01110001.11010011 is 203.0.113.211.

Remote Data Delivery

• The destination IP address delivers data to a remote network.

UTP Cable Connections

• Straight-through UTP cables connect a PC to a switch port.

Crosstalk

• Crosstalk is the distortion of transmitted messages from signals carried in adjacent wires.

IPv4 vs IPv6 Addresses Length

• IPv4 addresses are 32 bits in length.
• IPv6 addresses are 128 bits in length.

IPv4 vs IPv6 Address Representation

• IPv6 addresses are represented by hexadecimal numbers.
• IPv4 addresses are represented by dotted decimal numbers.

Auto-MDIX

• Auto-MDIX detects the Ethernet cable type.

Multicast MAC Address

• The address 01-00-5E is assigned to the first 24 bits of a multicast MAC address.

CSMA/CA

• CSMA/CA manages contention-based access on a wireless network.

Media Access Control

• Media access control may be affected by how nodes share the media.

Data Link Layer Addresses

• The data link layer addresses are used for local delivery.

Internet Layer Protocol

• ICMP functions as a protocol at the internet layer.

Protocols in Data Communications

• Protocols in data communications provide the rules required for a specific type of communication to occur.

Throughput

• Throughput measures the bits transferred across the media over a given period of time.

Wireless LAN Standards

• IEEE develops wireless LAN standards.

DHCP

• DHCP provides the automatic assignment of an IP address to each host.

Spyware

• Spyware secretly collects website data visited by users.

Multicast Address Reach

• The address 01-00-5E-0A-00-02 reaches a specific group of hosts.

Layering of Networking Model - Piece of Data

• PDU is the piece of data at any layer of a networking model.

Loopback Interface

• An IPv4 address of 127.0.0.1 is used to ping the loopback interface.

Message Reception

• Decoding process receives transmitted data and converts it into a readable message.

IP Packet Transmission

• An IP packet is encapsulated in a Layer 2 frame before transmission over the physical medium.

IPv4 Address Format

• The IPv4 address format created for ease of use is dotted decimal.

Binary Address Representation

• The dotted decimal format of the binary address 11101100 00010001 00001100 00001010 is 236.17.12.10.

Decimal Equivalent

• 201 is the decimal equivalent of 0xC9.

Ethernet Identifier

• MAC address identifies data uniquely at the data link layer of an Ethernet device.

NIC Attribute

• MAC address is an attribute of a NIC that would place it at the data link layer of the OSI model.

Full-Duplex Mode

• Full-duplex mode transmits data over the network in both directions at the same time.

LLC sublayer Function

• The LLC sublayer identifies which network layer protocol is being used.

OSI Model Data Link Layer Sublayers

• MAC and LLC are the two sublayers of the OSI model data link layer.

OSI Model Layer of Encapsulation

• The data link layer of the OSI model specifies the encapsulation method used for specific types of media.

Ethernet Cables Topology

• By connecting all Ethernet cables to a central device, the type of physical topology created is a star.

MAC Address Characteristic

• MAC addresses must be globally unique.

Ethernet Frame Host Reception

• A host on an ethernet network discards Ethernet frames that it recieves when the destination MAC address doesn't match its own.

Destination MAC Address

• Devices forward network traffic through MAC address.
• Switches make forwarding decisions, based on the destination MAC address.

LLC Sublayer Functions

• Interacts with upper protocol layers.
• Responsible for media access control.
• Adds a header and a trailer to form an OSI Layer 2 PDU.

Source Layer 2 Address

• Switches record the source Layer 2 address of incoming frames to build up its MAC address table.

Frame Address

• An address of 01-00-5E-0A-00-02 represents a specific group of hosts.

MAC Address Assignment

• The first three bytes of a MAC addresses are used by the vendor assigned OUI.

Online Shopping Network Access

• In order to do online shopping a home user must access the Internet.

Secure Remote Access

• A VPN, would allow an employee to gain secure remote access to a company network.

Internet Connection

• Cellular and satellite are two Internet connection options that do not require physical cables.

The Internet

• The Internet provides connections through interconnected global networks.

WISP - Rural Broadband Access

• The use of WISP is recommended in A farm in a rural area without wired broadband access

Large Geographic Networks

• MAN covers large geographic areas (districts, cities).

Guided Media

• Wireless LAN is not a guided media.

Default SVI on Cisco Switch

• VLAN1 is the default SVI on a Cisco switch.

Cisco Router Security

• Privileged EXEC is the type of access secured on a Cisco router or switch with the enable secret command.

Volatile Memory Location

• RAM is the memory location on a Cisco router or switch that loses all content when the device is restarted.

Security Threat

• A software secretly collecting data about visited web sites is a spyware.

Secure Corporate Network

• Extranet provides secure access to the corporate offices by suppliers, customers and collaborators

Large Corporations and Device Access

• When a large corporation allows users to network resources from personal devices, bring your own device is used.

Organization for Individuals

• Individual access the Internet though ISP.

Confidential Pricing Information

• Intranet provides confidential pricing information.

Connect Existing Devices

• Powerline networking technology connects existing home LAN using an adapter and an existing electrical outlet.

Security Breaches

• A network that allows patients to see others' records violates security.

Criteria to Select Medium

• Distance
• Environment

QoS network traffic

• Video conferencing requires QoS

Office Security

• Firewalls
• Antivirus software

Passwords in IOS

• VTY Interface
• Console Interface
• Privileged EXEC mode

L2 Switch Mode

_ The switch virtual interface allows remote management of a Layer 2 switch.

Process in Partial Type Word

• You can complete a partially typed word in IOS with hitting the Tab key.

NVRAM

• A technician can issue a reload command without saving the running configuration in NVRAM.

Key Strokes to Ping Command

• The Ctrl-Shift-6 interrupts the ping process command on the switch.

Device in IOS

• RAM is a Cisco Device.

Secure SVI

• It is not associated with any physical interface on a switch.
• It provides the same wireless.
• And LAN defualt, and is default to SVI.

Interface Condition

• show ip interface brief is used to verify the condition of the device and including configured the Ip adresses.

Unencrypted Passwords

• The (config)# service password-encryption will prevent all unencrypted passwords.

Encapsulation

• Encapsulation is a flow control that is used by two computers.

TCP/IP Model

• Through segmentation is sending data on segments.

Layer in Protocol

• FTP
• DHCP
• Transport Layer

Actions Performed By Cisco Switch

• Building MAC and IP address when building.
• Using source and destination addresses.

Function of Sublayer

• auto-MDIX enables the interface to automatically configure a straight.

1/ Cut Through

• lower density.

Multicast MAC Address

• 5E

Fiber or Coper

• Fiber is better due to the loss of signal
• Run greater distances