# data[].attributes.attachment_link.readable_text
VMware Fusion delivers the best way to run Windows on the Mac, and the ultimate development and testing tool for building apps to run on any platform.

Ready for macOS 11.0 Big Sur, Fusion 12 supports macOS 10.15 Catalina and includes new features for developers, IT admins and everyday users.

Fusion 12 Pro and Fusion 12 Player both now provide DirectX 11 3D accelerated graphics on Windows 10 virtual machines, added support for eGPUs and USB 3.1 devices, improved performance and security, as well as new CLI support for local Kubernetes clusters and OCI containers.

Use the links below to start your free, fully functional 30-day trial, no registration required.

# data[].attributes.attachment_link.description
VMware Fusion delivers the best way to run Windows on the Mac, and the ultimate development and testing tool for building apps to run on any platform. Ready for macOS 11.0 Big Sur, Fusion 12 supports macOS 10.15 Catalina and includes new features for developers, IT admins and everyday users.

# data[].attributes.attachment_link.readable_text
The item you are trying to access is restricted and requires additional permissions!

If you think you should have access to this file, please contact Customer Service for further assistance.
Contact Customer Service

# data[].attributes.attachment_link.description
The item you are trying to access is restricted and requires additional permissions! If you think you should have access to this file, please contact Customer Service for further assistance. Contact Customer Service

# data[].attributes.headline
Webopedia: Online Tech Dictionary for IT Professionals

# data[].attributes.subject
Webopedia: Online Tech Dictionary for IT Professionals

# data[].attributes.attachment_link.readable_text
The IP address 127.0.0.1 is a special-purpose IPv4 address and is called the localhost or loopback address. All computers use this address as their own, but it doesn't let computers communicate with other devices as a real IP address does.

Your computer might have the 192.168.1.115 private IP address assigned to it so that it can communicate with a router and other networked devices. However, it still attaches the special 127.0.0.1 address as something like an alias to mean, in networking terms, this computer.

The loopback address is only used by the computer you're on, and only for special circumstances-unlike a regular IP address that transfers files to and from other networked devices. For example, a web server running on a computer can point to 127.0.0.1 so that the pages run locally and test before it's deployed.

How 127.0.0.1 Works

All messages generated by TCP/IP application software contain IP addresses for their intended recipients. TCP/IP recognizes 127.0.0.1 as a special IP address. The protocol checks each message before sending it to the physical network. Then, it automatically re-routes any messages with a destination of 127.0.0.1 back to the receiving end of the TCP/IP stack.

To improve network security, TCP/IP also checks incoming messages arriving on routers or other network gateways and discards any that contain loopback IP addresses. This doublecheck prevents a network attacker from disguising their traffic as coming from a loopback address.

Application software typically uses this loopback feature for local testing purposes. Messages sent to loopback IP addresses like 127.0.0.1 do not reach outside to the local area network. Instead, messages are delivered directly to the TCP/IP and receive queues as if they had arrived from an outside source.

Loopback messages contain a destination port number in addition to the address. Applications can use these port numbers to subdivide test messages into multiple categories.

Localhost and IPv6 Loopback Addresses

The name localhost also carries a special meaning in computer networking used in conjunction with 127.0.0.1. Computer operating systems maintain an entry in their host's files associating a name with the loopback address. This practice helps applications create loopback messages using a name rather than a hard-coded number.

Internet Protocol v6 implements the same concept of a loopback address as IPv4. Instead of 127.0.0.01, IPv6 represents its loopback address as ::1 (0000:0000:0000:0000:0000:0000:0000:0001) and, unlike IPv4, it does not allocate a range of addresses for this purpose.

127.0.0.1 vs. Other Special IP Addresses

IPv4 reserves all addresses in the range 127.0.0.0 up to 127.255.255.255 for use in loopback testing, although 127.0.0.1 is (by convention) the loopback address used in almost all cases.

127.0.0.1 and other 127.0.0.0 network addresses do not belong to any of the private IP address ranges defined in IPv4. Individual addresses in those private ranges can be dedicated to local network devices and used for inter-device communication, whereas 127.0.0.1 cannot.

People studying computer networking sometimes confuse 127.0.0.1 with the 0.0.0.0. IP address. While both have special meanings in IPv4, 0.0.0.0 does not provide any loopback functionality.

Thanks for letting us know!

Other Not enough details Hard to understand

# data[].attributes.attachment_link.title
What's so Special About 127.0.0.1 in Computer Networking?

# data[].attributes.attachment_link.description
The IP address 127.0.0.1 is a special-purpose IPv4 address and is called the localhost or loopback address. All computers use this address as their own, but it doesn't let computers communicate with other devices as a real IP address does.

# data[].attributes.body
https://www.youtube.com/watch?v=AOGD2OaV1aQ

# data[].attributes.body
http://www.engineeringradio.us/blog/2013/01/subnetting-101/

# data[].attributes.body
CCNAC (ITN): The Important Thing Summarizer

CCNAC (RSE): The Important Thing Summarizer

CCNAC (SN): The Important Thing Summarizer

CCNAC (CCNA Prep): The Important Things Summarizer

# data[].attributes.body
Practical Packet Analysis, 3rd Edition

# data[].attributes.body
I can see the 7 layers of the OSI model clearly in output.

In using wireshark, I notice the...

# data[].attributes.body
Access Method- set of rules used by LAN hardware to direct traffic on the network.

Bandwidth- The rated throughput capacity of a given network medium or protocol.

Broadcast- A form of transmission where on device transmits to all devices within the network
or on another network.

Classful Addressing-A unicast IP address that is considered to have
three parts: a network, subnet, and host

Classless addressing- An IPv4 addressing scheme that uses a subnet mask that does not
follow classful addressing limitations.Provides increase flexibility when dividing ranges
of ip addresses into separate networks.

Client-A network device that accesses a sevice on another computer remotely through a network.

Command-line Interface(CLI)-User interface to a computer OS or application that depends on
textual commands.

Connectionless- Term used to describe data transfer without the existence of virtual client.

Destination IP Address- The Layer 3 address to which data is going.

Fault Tolerant- Limits the impact of a failure so that fewest number of devices are affected.

Flow Control-The management of data flow between devices in a network.

Full Duplex-Both Devices an transmit and recieve on the media at the same time.

Half Duplex- Both devices can transmit and receive on the same media but cannot do so
simultaneously.

IEEE-maintains the standards for defining many LAN protocols

ISO- International Standards body that defines many network standards.

Kernel -The portion of the operating system that interacts directly with the computer hardware.

Latency- the amt of time, to include delays, for data to travel from one given point to another.

Medium- Provides the channel over which the message travels from source to destination.

Multiplexing- A process where multiple digital data streams are combined into one signal

Physcial Media-The cabling and connectors used in interconnect the network devices.

PDUs (Protocol data Unit)- A generic term from OSI that refers to the data, header, and trailers about which a
particular networking layer is concerned

QoS- A control mechanism that can provide different priorities to different users of data flows or guarantee
a certain level of performance to a data flow in accordance with requests from the application program.

Shell- the portion of the Operation system that interfaces with application and the user.

Spoofing- A person or program that masquerades as another to gain access to data and the network.

Stateful- Tracking of actual conversations and their state of communication session for the protocol such as TCP.

SVI-Virtual- interfaces for which there is no physical hardware on the device associated.

Throughput-The actual data transfer rate between two computers at some point in time.

Tunneling- Encapsulation an IP packet inside another IP packet.

Unicast- Message sent to a single network destination.

# data[].attributes.body
In Conf T mode:

username

# data[].attributes.body
In EXEC mode -

To backup:
copy running-config tftp:
Then enter creds.

To restore:
copy tftp: running-config
Enter creds.

-Matt

# data[].attributes.body
Dual Stacking
Corp(config)#ipv6 unicast-routing

Corp(config)#interface fastethernet0/0

Corp(config-if)#ipv6 address 2001:db8:3c4d:1::/64 eui-64

Corp(config-if)#ipaddress 192.168.255.1 255.255.255.0

# data[].attributes.body
IPv6 Routing Protocols
RIPng
Router1(config-if)#ipv6 rip 1 enable
EIGRPv6
Router1(config)#ipv6 router eigrp 10
Router1(config-rtr)#no shutdown
OSPFv3
Router1(config)#ipv6 router osfp 10
Router1(config-rtr)#router-id 1.1.1.1
Router1(config-if)#ipv6 ospf 10 area 0.0.0.0

# data[].attributes.body
IPv6 Address Types
Address Type Description
Unicast
-One to One (Global, Link local, Site local)
- An address destined for a single interface.

Multicast
One to Many
-An address for a set of interfaces
-Delivered to a group of interfaces identified by that address.
-Replaces IPv4 “broadcast”
Anycast
One to Nearest (Allocated from Unicast)
-Delivered to the closest interface as determined by the IGP

A single interface may be assigned multiple IPv6 addresses of any type (unicast,
anycast, multicast)

# data[].attributes.headline
How to configure IPv6 on switch or Router

# data[].attributes.subject
How to configure IPv6 on switch or Router

# data[].attributes.body
ipv6 unicast-routing.

ipv6 address ipv6-prefix/prefix-length eui-64. ipv6 address ipv6-prefix/prefix-length link-local. ipv6 address ipv6-prefix/prefix-length anycast. ipv6 enable.
**exit
**ipv6 unicast-routing.

# data[].attributes.body
Identity theft is the crime of obtaining the personal or
financial information of another person for the sole
purpose of assuming that person's
name or identity to make transactions or purchases.

Data Loss & Manipulation- Breaking into a computer to destroy or alter data records

Identity Theft -also known as identity fraud,
is a crime in which an imposter obtains key pieces of personally
identifiable information, such as Social Security or driver's
license numbers, in order to impersonate someone else.

Disruption of Service-prevention legit users
from accessing services to which they should be entitled.

# data[].attributes.body
Computer security reconnaissance is a type of computer attack in which an intruder engages with the targeted system to gather information about vulnerabilities. The attacker first discovers any vulnerable ports by using software's like port scanning.

Access attacks-unauthorized manipulation of data, system access or user privileges.

Denial of Service-disabling or corruption of network, systems or services

# data[].attributes.body
Computer security reconnaissance is a type of computer attack in which an intruder engages with the targeted system to gather information about vulnerabilities. The attacker first discovers any vulnerable ports by using software's like port scanning.

Access attacks-unauthorized manipulation of data, system access or user privileges.

Denial of Service-disabling or corruption of network, systems or services

# data[].attributes.body
http://www.ciscopress.com/articles/article.asp?p=2202410&seqNum=4

# data[].attributes.headline
Command for password encrypt, domain name, banner for Router

# data[].attributes.subject
Command for password encrypt, domain name, banner for Router

# data[].attributes.body
Configuration for password, banner, domain name, on a Router

router(config)#Banner motd “Authorized Access Only”
router(config)#security password min-length 10
router(config)#service password-encryption
router(config)#ip domain-name give a domain name
router(config)#username cisco secret "give a secret passwd"
router(config)#crypto key generate rsa
The name for the keys will be: "name the keys"

How many bits in the modulus [512]: 1024
% Generating 1024 bit RSA keys, keys will be non-exportable…[OK]

# data[].attributes.body
show running-config
show ip interface brief
show interfaces
show arp
show ip route
show protocols
show version

# data[].attributes.body
http://www.he.com

# data[].attributes.body
http://www.packetlife.net

http://tcpipguide.com

http://www.webopedia.com

# data[].attributes.body
https://www.sans.org/

# data[].attributes.body
Netspace

Cisco Learning Network

NETLAB

Cisco 3D Interactive Catalog

# data[].attributes.body
http://www.subnettingquestions.com/

# data[].attributes.body
PSH flag is also used to facilitate real-time communication via TCP. TCP's push capability accomplishes two things:

The sending application informs TCP that data should be sent immediately.

The PSH flag in the TCP header informs the receiving host that the data should be pushed up to the receiving application immediately.

# data[].attributes.body
Routers and switches on a network simultaneously running and transporting IPv6 and IPv4

# data[].attributes.headline
Tunneling encapsulates IPv6 into packets that can be sent over IPv4 networks

# data[].attributes.subject
Tunneling encapsulates IPv6 into packets that can be sent over IPv4 networks

# data[].attributes.body
https://www.youtube.com/watch?v=ZxAwQB8TZsM
-matt

# data[].attributes.body
R1#config t
R1(config)#hostname I_Am_Router
I_Am_Router#end
show run

# data[].attributes.headline
There is a trick in the Chapter 6 Skills Integration Challenge -- a flaw in the addressing.

# data[].attributes.subject
There is a trick in the Chapter 6 Skills Integration Challenge -- a flaw in the addressing.

# data[].attributes.body
Transport Layer encapsulate data into segments by adding TCP header; Network Layer encapsulates segements into packets - adds IP header; Datalink encapsulates into frames by adding MAC header, LLC header and the FCS; then into bits by the physical layer onto the media.

They travel from the layers down to the physical layer, then to the destination physical layer then it gets de-encapsulated in reverse order of the above process.

# data[].attributes.body
TCP -- Transmission Control Protocol

EIGRP -- Enhanced Interior Gateway Routing Protocol

DHCP -- Dynamic Host Configuration Protocol

DNS -- Domain Name System

FTP -- File Transfer Protocol

FCS -- Frame Check Sequence

HTTP -- Hypertext Transfer Protocol

IMAP -- Internet Message Access Protocol

SMTP -- Simple Mail Transfer Protocol

SSH -- Secure Shell

UDP -- User Datagram Protocol

IP -- Internet Protocol

ICMP -- Internet Control Message Protocol

ARP -- Address Resolution Protocol

DSL -- Digital Subscriber Line

MAC -- Media Access Control

BOOTP -- Bootstrap Protocol

# data[].attributes.body
10111111= 191
01111111=127

# data[].attributes.body
Application
Presentation
Session
Transport
Network
Data Link
Physical

# data[].attributes.body
Help with Binary

# data[].attributes.headline
Use PuTTY to console in and configure a switch or router.

# data[].attributes.subject
Use PuTTY to console in and configure a switch or router.

# data[].attributes.body
0-9
A=10
B=11
C=12
D=13
E=14
F=15

# data[].attributes.body
Split the 8 bit binary code into two groups of four bits each, calculate the binary value (8,4,2,1) and assign hex value according to the table above.

# data[].attributes.body
I can recall the OSI Reference Model and compare it to the TCP/IP Model.

# data[].attributes.body
I can list ten protocols and describe five of them to another person.

# data[].attributes.body
http://www.webopedia.com/quick_ref/OSI_Layers.asp

# data[].attributes.body
http://media.packetlife.net/media/library/images/tn_common_ports.pdf.jpg

# data[].attributes.body
I can navigate the modes of the IOS and use the help features to identify available commands.

# data[].attributes.body
I can access the CLI of IOS of a device, by connecting the correct cable to the correct interface, using emulation software.

I can identify the different copper medium.

# data[].attributes.body
I can calculate and convert between Base2, Base10 and Base16 numbering systems

I remember patterns: 160, 80, 40, 20, 10, 5; 128, 192, 224, 240, 248, and can count the rest?

# data[].attributes.body
Base-16: 1, 16
0-9
10 = A; 11 = B; 12 = C; 13 = D; 14 = E
15 = F

# data[].attributes.body
Base-2: 1, 2, 4, 8, 16, 32, 64, 128

# data[].attributes.body
Base-10: 1, 10, 100, 1000, etc

# data[].attributes.body
1. Cross-connect cable
connects like devices (eg. computer to computer)
568B on one side, 568A on the other
inband

2. Straight-through cable connects different devices (eg. computer to switch)
both sides are the same: 568B each
in-band

3. Console\Rollover cable connects out-of-band devices for initial configuration

# data[].attributes.body
Switch, Router, Wireless Router, Firewall

# data[].attributes.body
Desktop, Laptop, Printer, etc.