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Wednesday, April 17, 2019

Which routing protocol is designed to use areas to scale large hierarchical networks?

Which routing protocol is designed to use areas to scale large hierarchical networks?

  • BGP
  • OSPF
  • EIGRP
  • RIP

Which routing protocol is designed to use areas to scale large hierarchical networks?

EXPLANATION

Border Gateway Protocol is a standardized exterior gateway protocol designed to exchange routing and reachability information among autonomous systems on the Internet. The protocol is classified as a path vector protocol

Open Shortest Path First is a routing protocol for Internet Protocol networks. It uses a link state routing algorithm and falls into the group of interior gateway protocols, operating within a single autonomous system. It is defined as OSPF Version 2 in RFC 2328 for IPv4. The updates for IPv6 are specified as OSPF Version 3 in RFC 5340. OSPF supports the Classless Inter-Domain Routing addressing model.

 Enhanced Interior Gateway Routing Protocol is an advanced distance-vector routing protocol that is used on a computer network for automating routing decisions and configuration. The protocol was designed by Cisco Systems as a proprietary protocol, available only on Cisco routers. Partial functionality of EIGRP was converted to an open standard in 2013 and was published with informational status as in 2016.

 The Routing Information Protocol is one of the oldest distance-vector routing protocols which employ the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from source to destination. The largest number of hops allowed for RIP is 15, which limits the size of networks that RIP can support.

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In a virtual environment that includes a SAN and VMware ESXI 5.0 or later, which of these steps would you perform last (before re-scanning storage adapters) when removing a storage LUN?

In a virtual environment that includes a SAN and VMware ESXI 5.0 or later, which of these steps would you perform last (before re-scanning storage adapters) when removing a storage LUN?

  • Verify that the LUN is no longer used for storing VMs, templates, HA heartbeats, etc.
  • Detach LUN in VMware client
  • Disconnect LUN in SAN interface
  • Unmount datastore  [Partially Correct Please share your answers on commnet box]


EXPLANATION

Removing a LUN in ESXi/ESX 4.x is complex. Improvements are made in ESXi 5.0 and later to streamline the procedure to make it easier for Administrators to remove LUNs.
 

Unmounting a LUN checklist

Before unmounting a LUN, ensure that:
  • If the LUN is being used as a VMFS datastore, all objects, (such as virtual machines, snapshots, and templates) stored on the VMFS datastore are unregistered or moved to another datastore.

    Note: All CD/DVD images located on the VMFS datastore must also be unregistered from the virtual machines.
     
  • The datastore is not used for vSphere HA heartbeat.
  • The datastore is not part of a datastore cluster.

  SOURCE

 https://kb.vmware.com/s/article/2004605

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What is not a standard windows UART baud rate?

What is not a standard windows UART baud rate?

  • 150 Baud
  • 300 Baud
  • 55 Baud
  • 110 baud 

What is not a standard windows UART baud rate?

EXPLANATION

It started a long long time ago with teletypes — I think 75 baud. Then it's been mostly doubling ever since, with a few fractional (x1.5) multiples, for example 28,800, where there were constraints on phone-line modem tech that didn't quite allow it to double. Standard crystal values came from these early baudrates, and their availability dictates future rates. E.g.,

Most UARTS use a clock of
of the baudrate, more modern parts (e.g. NXP LPC) have fractional dividers to get a wider range by using non-binary multiples.
Other common standards are 31,250 (MIDI) and 250K (DMX), both likely chosen as nice multiples of 'round' clocks like 1MHz etc.

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What technology is not used to implement confidentiality?

What technology is not used to implement confidentiality?

  • Access Controls
  • Authentication
  • Auditing
  • Encryption 

What technology is not used to implement confidentiality?

EXPLANATION

What technology is not used to implement confidentiality, but is used verify that an administrator is not accessing data that he should not be accessing? Auditing

SOURCE

https://quizlet.com/111340244/understanding-security-layers-lesson-1-flash-cards/

 

 


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Which one is NOT one of the 4 layers of the TCP/IP model

Which one is NOT one of the 4 layers of the TCP/IP model

  • Data
  • Internet
  • Application
  • Network access


Which one is NOT one of the 4 layers of the TCP/IP model

 EXPLANATION

Layer 4. Application Layer

Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.
Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.


Layer 3. Transport Layer

Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.
The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

Layer 2. Internet Layer

Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagrams, which contain source and destination address (logical address or IP address) information that is used to forward the datagrams between hosts and across networks. The Internet layer is also responsible for routing of IP datagrams.
Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.
The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

Layer 1. Network Access Layer

Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.
The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.
The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.
IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

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What does the acronym GNU stand for?

What does the acronym GNU stand for?

  • Guaranteed Not Unix
  • GNU's Not Unix
  • Genuine Non-Unix
  • Gratis Not Unix 

What does the acronym GNU stand for?

EXPLANATION

In computing, an early tradition in the hacker community (especially at MIT) was to choose acronyms and abbreviations that referred humorously to themselves or to other abbreviations. Perhaps the earliest example in this context – from 1960 – is the backronym "Mash Until No Good", which was created to describe Mung, and a while later was revised to "Mung Until No Good". It lived on as a recursive command in the editing language TECO.[3] In 1977 or 1978 came TINT ("TINT Is Not TECO"), an editor for MagicSix written (and named) by Ted Anderson. This inspired the two MIT Lisp Machine editors called EINE ("EINE Is Not Emacs", German for one) and ZWEI ("ZWEI Was EINE Initially", German for two). These were followed by Richard Stallman's GNU (GNU's Not Unix).
Many others also include negatives, such as denials that the thing defined is or resembles something else (which the thing defined does in fact resemble or is even derived from), to indicate that, despite the similarities, it was distinct from the program on which it was based.[3]
An earlier example appears in a 1976 textbook on data structures, in which the pseudo-language SPARKS is used to define the algorithms discussed in the text. "SPARKS" is claimed to be a non-acronymic name, but "several cute ideas have been suggested" as expansions of the name. One of the suggestions is "Smart Programmers Are Required to Know SPARKS".[4] (this example is tail recursive)

SOURCE

https://en.wikipedia.org/wiki/Recursive_acronym

 

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The password management system found in MacOS is known as...

The password management system found in MacOS is known as...

  • Keychain
  • Key Ring
  • Key Fob
  • Key Grip 
 


EXPLANATION

Keychains were originally developed in the early 1990s for use with an Apple email system called PowerTalk. The idea was that PowerTalk could communicate with many mail servers and online services, so it would use a keychain file to hold user authentication information within the application to automatically and securely log the user into the variety of services. With the creation and release of Mac OS X in the early 2000s, Keychain became part of the operating system and was used to hold much more information.
 a secure database of a users passwords
-2 default chains: System and System Roots (belong to the OS)
-use Keychain Access utility to create multiple keychains







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