Term
| What is the purpose of DNS? Who runs it? |
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Definition
A hierarchical, distributed database that contains mappings of domain names to IP addresses.
Maps IP addresses to names
Authority is hierarchical – delegated to lower levels
DNS enables the location of computers and services by user-friendly names.
ICANN runs it |
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Term
| DNS is a layer on top of_____? |
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Definition
| the Internet rather than an integral part of the internet |
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Term
| Be able to explain how authority in DNS is delegated and how it is controlled. |
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Definition
| {host name.}[subdomain.[subdomain.]…][domain][.] |
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Term
| Understand the various domain levels, what they represent, and who controls them. |
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Definition
domain root - representing an unnamed level. When used in a DNS domain name, it is stated by a trailing period (.) to designate that the name is located at the root or highest level of the domain hierarchy. Names stated this way are called fully qualified domain names (FQDNs).
Top-level domain - Name of two or three letters used to indicate a country/region or the type of organization using a name. (.com .org .edu)
Second-level domain - Variable-length names registered to an individual or organization for use on the Internet. These names are always based upon an appropriate top-level domain, depending on the type of organization or geographic location where a name is used. (E.g. fullsail.com)
Subdomain - Additional names that an organization can create that are derived from the registered second-level domain name. Typically divided into departments or geographic locations.
(E.g. systems.fullsail.com)
Host or resource name - Names that represent a leaf in the DNS tree of names and identify a specific resource. Typically, the leftmost label of a DNS domain name identifies a specific computer on the network.
(E.g. host-a.systems.fullsail.com) |
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Term
| Know in detail the process involved in resolving a DNS request. |
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Definition
1. Resolution request for website
2. Resolution request for...website..again?
3. return the name server for .com
4. resolution request for msdn.microsoft.com
5. return the name server for microsoft.com
7. return the address for the msdn.microsoft.com server
8. resolution request for msdn.microsoft.com
9. return the IP address for the msdn.microsoft.com server |
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Term
| What is dynamic DNS, what does it do, and why is it useful? |
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Definition
it updates the DNS master file dynamically
typically used on servers that use a dynamic IP address.
client program informs the DNS server when the IP address changes
It is used for:
Local Host lookup
Master server lookup
personal internet gaming |
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Term
| Understand what the “hosts” file is and its purpose. |
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Definition
C:\Windows\system32\drivers\etc\hosts or
/etc/hosts
Hosts
Name mappings to IP addresses
Protocol
Services |
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Term
| What is the address-size of IPv6 and approximately how many addresses are there? |
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Definition
128-bit
3.4X10^38 (AKA a metric ass-ton) |
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Term
| What is the address-size of IPv4 and approximately how many addresses are there? |
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Definition
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Term
| Know the various ways to abbreviate an IPv6 address. |
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Definition
take out useless zeroes
combine entire repeating zero sections into :: (can only be done once) |
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Term
| What is the equivalent to 127.0.0.1 in IPv6? |
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Definition
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Term
| What is the equivalent to 0.0.0.0 in IPv6 |
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Definition
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