Which one is a logical address?

Which one is a logical address?

• MAC address
• NAT address
• IP address
• Mailing address 

 EXPLANATION

Internet Protocol version 4 (IPv4) defines an IP address as a 32-bit number.^[2] However, because of the growth of the Internet and the depletion of available IPv4 addresses, a new version of IP (IPv6), using 128 bits for the IP address, was developed in 1995,^[3] and standardized in December 1998.^[4] In July 2017, a final definition of the protocol was published.^[5] IPv6 deployment has been ongoing since the mid-2000s.
IP addresses are usually written and displayed in human-readable notations, such as 172.16.254.1 in IPv4, and 2001:db8:0:1234:0:567:8:1 in IPv6. The size of the routing prefix of the address is designated in CIDR notation by suffixing the address with the number of significant bits, e.g., 192.168.1.15/24, which is equivalent to the historically used subnet mask 255.255.255.0.
The IP address space is managed globally by the Internet Assigned Numbers Authority (IANA), and by five regional Internet registries (RIRs) responsible in their designated territories for assignment to end users and local Internet registries, such as Internet service providers. IPv4 addresses have been distributed by IANA to the RIRs in blocks of approximately 16.8 million addresses each. Each ISP or private network administrator assigns an IP address to each device connected to its network. Such assignments may be on a static (fixed or permanent) or dynamic basis, depending on its software and practices.

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What is CIDR when addressing a network subnet?

What is CIDR when addressing a network subnet?

• Classless Inter-Domain Routing
• Class Inter-Domain Routing
• Classless Inter-Domain Racking
• Drinking apple CIDR with a kick before starting 

EXPLANATION

  Classless Inter Domain Routing (CIDR) is a method for assigning IP addresses without using the standard IP address classes like Class A, Class B or Class C. CIDR is a newer addressing scheme for IP Networks which allows for a more efficient allocation of IP addresses than the older method which was by assigning organizations a class of IPs. CIDR was a result of running out of IPv4 addresses as well as addressing the issue with routing tables increasing in size.

There is a maximum number of networks and hosts that can be assigned unique IP addresses using the 32 bit addressing. Traditionally, the Internet assigned "classes" of addresses: Class A, Class B and Class C were the most common. Many large organizations were assigned Class A blocks. Others were assigned Class B blocks. The smaller organizations were assigned Class C blocks. Not all organizations used all of the IP addresses within the block they were assigned. This resulted in an inefficent use of the addressing scheme. For this reason, the Internet was, until the arrival of CIDR, running out of address space very quickly. CIDR effectively solved the problem by providing a new and more flexible way to specify network addresses.

Class	Network Bits	Host Bits	Decimal Range
Class A	8	24	1-126
Class B	16	16	128-191
Class C	24	8	192-223

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Which one of the following is a common problem that plagues VoIP?

Which one of the following is a common problem that plagues VoIP?

• Buffers
• Critters
• Bitters
• Jitters

EXPLANATION

Jitters, they're not just for coffee addicts anymore. Because the information is divided into packets, each packet can travel by a different path from the sender to the receiver.
When packets arrive at their intended destination in a different order then they were originally sent, the result is a jitter, a call with poor or scrambled audio.

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Which operating system would not be able to boot if it were installed on an NVMe drive?

Which operating system would not be able to boot if it were installed on an NVMe drive?

• Windows XP
• Windows 7
• Windows 8.1
• Windows 10 

 

EXPLANATION

Windows XP is too old, and there are no NVMe drivers available for it. Newer motherboards (Skylake and newer) that can boot from NVMe also will not support Windows XP.

SOURCE

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In the 3-2-1 backup strategy, what does the 2 stand for?

In the 3-2-1 backup strategy, what does the 2 stand for?

• 2 different admins
• 2 different locations
• 2 different media types
• 2 different copies 

EXPLANATION

The 3-2-1 backup strategy states that every bit of data should be backed up to, at the very least:

• 3 different copies
• 2 different types of media
• 1 off-site backup

This helps to ensure that if a copy is corrupt, there will be another copy available; that if there's something wrong with the primary media type, that there will be an additional media type to try; and that if something bad happens at the primary site to cause everything to be lost there, at least one other copy will be available to restore from elsewhere.
It does not include any details about how many backup administrators should be available, although having backup administrators is rarely a bad idea.
An external source that talks about this backup plan is http://www.networkcomputing.com/storage/3-2-1-backup-rule-recovery/108368175

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A DNS SPF record is for:

A DNS SPF record is for:

• Identifying mail server IP address(es) authorized to send on a domains behalf
• Resolving an ip address from a fully qualified host name
• Resolving the address of a mail server responsible for accepting mail messages on behalf of a domain
• Resolving an alias name to a host 

EXPLANATION

A Sender Policy Framework (SPF) record is a type of Domain Name Service (DNS) TXT record that identifies which mail servers are permitted to send email on behalf of your domain. The purpose of an SPF record is to detect and prevent spammers from sending messages with forged From addresses on your domain.  

An SPF record is a Sender Policy Framework record. It's used to indicate to mail exchanges which hosts are authorized to send mail for a domain. It's defined in RFC 4408, and clarified by RFC 7208. SPF record format. SPF records are typically defined using the TXT record type.

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What was "SystemPro"

What was "SystemPro"

• The working title for AMD
• The "first" real PC based Server.
• The first chip from Intel
• The first user group for system administrators 

EXPLANATION

Compaq SystemPro

The SystemPro from Compaq, released in November 1989, was arguably the first true PC based server. It supported Intel's 486 chip, a 32-bit bus, RAID disk and dual-processor support well before its main rivals. 

Innovative features

The SystemPro, along with the simultaneously released Compaq Deskpro 486, was one of the first two commercially available computer systems containing the new EISA bus. The SystemPro was also one of the first PC-style systems specifically designed as a network server, and as such was built from the ground up to take full advantage of the EISA bus. It included such features as multiprocessing (the original systems were asymmetric-only), hardware RAID, and bus-mastering network cards. All models of SystemPro used a full-height tower configuration, with eight internal hard drive bays. 

 

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