CodeTextPro | Free Web Tutorial

CodeTextPro | Free Web Tutorial

Codetextpro Provides free Web tutorial, HTML, CSS, C, C++, Java, JavaScript, PHP, MySql, Python, Program, Programming Notes, Programming Questions and more.

Programming

Breaking

Monday, September 16, 2019

Improve Your Presentation Skills | Three P's of Presentation | CodeTextPro

9:00 AM 0
Improve Your Presentation Skills | Three P's of Presentation | CodeTextPro



Presentation Skills

A presentation is a means of communication that can be adapted to various speaking situations, such as talking to a group, addressing a meeting or briefing a team.

A presentation can also be used as a broad the term that encompasses other ‘speaking engagements’ such as making a speech at a wedding, or getting a point across in a video conference.

To be effective, step-by-step preparation and the method and means of presenting the information should be carefully considered.

A presentation requires you to get a message across to the listeners and will often contain a 'persuasive' element. It may, for example, be a talk about the positive work of your organization, what you could offer an employer, or why you should receive additional funding for a project.

The Key Elements of a Presentation

Making a presentation is a way of communicating your thoughts and ideas to an audience

Consider the following key components of a presentation:
Context

  • Ask yourself the following questions to develop a full understanding of the context of the presentation.
  • When and where will you deliver your presentation?
  • There is a world of difference between a small room with natural light and an informal setting, and a huge lecture room lit with stage lights. The two require quite different presentations, and different techniques.
  • Will it be in a setting you are familiar with, or somewhere new?
  • If somewhere new, it would be worth trying to visit it in advance, or at least arriving early, to familiarise yourself with the room.
  • Will the presentation be within a formal or less formal setting?
  • A work setting will, more or less by definition, be more formal, but there are also various degrees of formality within that.
  • Will the presentation be to a small group or a large crowd?
  • Are you already familiar with the audience?


    With a new audience, you will have to build rapport quickly and effectively, to get them on your side.

  What equipment and technology will be available to you, and what will you are expected to use?

 In particular, you will need to ask about microphones and whether you will be expected to stand in one place, or move around.

    What is the audience expecting to learn from you and your presentation?

    Check how you will be ‘billed’ to give you clues as to what information needs to be included in your presentation.

All these aspects will change the presentation. For more on this, see our page on Deciding the Presentation Method.


Presenter

The role of the presenter is to communicate with the audience and control the presentation.

Remember, though, that this may also include handing over the control to your audience, especially if you want some kind of interaction.

    You may wish to have a look at our page on Facilitation Skills for more.


Audience

The audience receives the presenter’s message(s).

However, this reception will be filtered through and affected by such things as the listener’s own experience, knowledge and personal sense of values.

    See our page: Barriers to Effective Communication to learn why communication can fail.


Message

The message or messages are delivered by the presenter to the audience.

The message is delivered not just by the spoken word (verbal communication) but can be augmented by techniques such as voice projection, body language, gestures, eye contact (non-verbal communication), and visual aids.

The message will also be affected by the audience’s expectations. For example, if you have been billed as speaking on one particular topic, and you choose to speak on another, the audience is unlikely to take your message on board even if you present very well. They will judge your presentation a failure because you have not met their expectations.


Reaction

The audience’s reaction and therefore the success of the presentation will largely depend upon whether you, as a presenter, effectively communicate your message, and whether it met their expectations.

As a presenter, you don’t control the audience’s expectations. What you can do is find out what they have been told about you by the conference organizers, and what they are expecting to hear. Only if you know that can you be confident of delivering something that will meet expectations.

    See our page: Effective Speaking for more information.


Method

How will the presentation be delivered?

Presentations are usually delivered directly to an audience.  However, there may be occasions where they are delivered from a distance over the Internet using video conferencing systems, such as Skype.

It is also important to remember that if your talk is recorded and posted on the internet, then people may be able to access it for several years. This will mean that your contemporaneous references should be kept to a minimum.


Impediments

Many factors can influence the effectiveness of how your message is communicated to the audience.

For example background noise or other distractions, an overly warm or cool room, or the time of day and state of audience alertness can all influence your audience’s level of concentration.

As a presenter, you have to be prepared to cope with any such problems and try to keep your audience focussed on your message.  


The three P's of presentation

Preparation

Confidence is a great selling point, feeling fully prepared when you go into a presentation is going to make you and your audience feel secure. When you are developing the content of your presentation, make sure you have a beginning, a middle and an end.

Make sure you understand the goals of the presentation; what do you and the audience need to get out of it? Ensure that you have your materials ready in plenty of time before you deliver, so you can set up quickly without adding to your nerves. Arrange them properly. Do the research nicely so that you can be having the proper knowledge to deal with the topic concerned.

Practice

Ahead of the day, practice what you are going to say, either to a mirror or a tolerant friend. This will help you to refine the narrative, ensure you get timings correct and as a result, you will come across as prepared and competent. You will also be more familiar with the presentation, which will help to reduce your nerves on the day.

Perform

If you are presenting for the first time or simply delivering new material, you need to accept that it may not be perfect. I’m an experienced trainer but when delivering new material, I will need to practice and finesse new elements before and after delivery. Hopefully, all will go very well. But if it doesn’t, learn from it, change it, prepare and practice for next time. The day is very important. Keep yourself as confident as possible. Take the time factor seriously. Be ready to make some necessary changes in your rehearsed presentation as and when the situation arises. Keep the audience attached to your presentation by making it interactive, adding interesting facts, making it interesting and respect their time.

Here are some more tips on perfecting your presentation skills:


Breathe

Breath is the engine of the voice, air from your lungs pass over your vocal cords and is transmitted to your audiences’ ears. So it is a good idea to breathe in before you speak.

Breathing is also a great way to combat nerves, a couple of good deep breaths before presenting increases oxygen in your system relaxing your muscles and energizing your brain.


Relax

Easier said than done, but if you follow the advice above it will help you to keep a level head and feel more in control of the situation. There are many relaxation techniques you can use to get you in the right frame of mind for presentation. Deep breathing, stretches and visualization can really help to combat nerves.


Know your audience

Research your audience just as vigorously as your content. Tailor your content to them, if they are technical include appropriate jargon and technical detail; if they are non-technical then avoid jargon and try using plain language instead.

Also, try to pre-empt the questions you may be asked during and after the presentation, you can prepare answers for the most commonly asked questions so the flow of the presentation isn’t interrupted and you appear knowledgeable and confident.

The critical outcome of any presentation is that the audience understands your message and your goals.

Winston Churchill wrote all his speeches for the comprehension of a 12-year-old, as he understood the power of simple words. Never try to impress anyone with your vocabulary, impress them with your knowledge, experience, and passion.

Saturday, September 14, 2019

What is a Flexible Single Master Operation (FSMO) | Roles of FSMO

9:16 PM 0
What is a Flexible Single Master Operation (FSMO) | Roles of FSMO



What does FSMO stand for?

FSMO stands for Flexible Single Master Operations, and FSMO roles (also known as operations master roles) help you prevent conflicts in your Active.


What is the role of PDC emulator?

The PDC Emulator (Primary Domain Controller) - This role is the most used of all FSMO roles and has the widest range of functions. The domain a controller that holds the PDC Emulator role is crucial in a mixed environment where Windows NT 4.0 BDCs are still present.


What FSMO role is the master time server?

Because an Active Directory role is not bound to a single DC, it is referred to as a Flexible Single Master Operation (FSMO) role. Currently, in Windows, there are five FSMO roles: Schema master. Domain naming master.


What is the schema master?

The Schema Master FSMO role owner is the DC responsible for performing updates to the directory schema. This DC is the only one that can process updates to the directory schema. Once the schema update is complete, it is replicated from the Schema Master FSMO role owner to all other DCs in the directory.


What is a RID in Active Directory?

The RID is a monotonically increasing number at the end of the SID. Each domain controller is assigned a pool of RIDs from the global RID pool by the domain controller that holds the RID master role (also known as flexible single master operations or FSMO) in each Active Directory domain. Nov 25, 2009


What is the Fsmo roles?

Active Directory knows seven FSMO roles with different scopes:**PDC Emulator (One per domain)**RID Master (One per domain)**Schema Master (One per forest)**Domain Naming Master (One per forest)**Infrastructure Master (One per domain)**Domain DNS Zone Master role (one per domain)**Forest DNS Zone Master role (one per forest)


What is a global catalog server?

The global catalog is the set of all objects in an Active Directory Domain Services (AD DS) forest. A global catalog server is a domain a controller that stores a full copy of all objects in the directory for its host domain and a partial, read-only copy of all objects for all other domains in the forest.


What is the use of global catalog in Active Directory?

The global catalog is the set of all objects in an Active Directory Domain Services (AD DS) forest. A global catalog server is a domain controller that stores a full copy of all objects in the directory for its host domain and a partial, read-only copy of all objects for all other domains in the forest


What is the child domain?

child domain is another domain under a parent one in an active directory domain hierarchy. A child domain under a parent first root domain form a Tree. All Trees exists within a Forest, a forest is the security boundary.

A domain tree is made up of several domains that share a common schema and configuration, forming a contiguous namespace. Domains in a tree are also linked together by trust relationships. Active Directory is a set of one or more trees. Trees can be viewed in two ways.


What is the use of additional domain controller?

With low network bandwidth or a large directory database, this replication can take hours or days to complete. With servers running Windows Server 2003, you can create an additional domain controller using a restored backup was taken from a domain controller running Windows Server




What is a forest in Active Directory?

A forest is a collection of one or more domains which may have one or more trees. What makes a forest unique is that it shares the same schema. The schema defines what and how Active Directory objects are stored.


What is the Active Directory service?

Active Directory services include Active Directory Certificate Services (AD CS), Active Directory Domain Services (AD DS), Active Directory Federation Services(AD FS), Active Directory Lightweight Directory Services (AD LDS), and Active Directory Rights Management Services (AD RMS).


What is a domain controller in Active Directory?

domain controller is a server that is running a version of the Windows Server® operating system and has Active Directory® Domain Services installed. Note. In Windows Server 2003 and Microsoft Windows® 2000 Server, the directory service is named Active Directory.


What is a member server?

A member server is a computer that runs an operating system in the Windows 2000 Server family or the Windows Server 2003 family, belongs to a domain, and is not a domain controller.


What is the meaning of standalone server?

A standalone server is a server that runs alone and is not a part of a group. In fact, in the context of Microsoft Windows networks, a standalone server is one that does not belong to or is not governed by a Windows domain.


What do you mean by client-server architecture?

Client-server architecture (client/server) is network architecture in which each computer or process on the network is either a client or a server. Servers are powerful computers or processes dedicated to managing disk drives (file servers), printers (print servers), or network traffic (network servers).


What is Correspondence? Meaning | Definition | Explanation

8:36 AM 0
What is Correspondence? Meaning | Definition | Explanation

What is correspondence? correspondents, meaning of correspond

Any written or digital communication exchanged by two or more parties. Correspondences may come in the form of letters, emails, text messages, voicemails, notes, or postcards. Correspondences are important for most businesses because they serve as a paper trail of events from point A to point B.

In simple Correspondence is communication in writing between two personsCorrespondence is communication in writing of ideas/opinions/views between friends /relatives /between business houses/officesMatters relating to personal matters/welfare/trade &commerce/official mattersCommunication takes place between parties living at distant places




Different kind of correspondence are-

Business documents:-Reports/proposals/procedures/manuals/guidelines/business plans/memorandum/letters/emails/circular/notices/newsletters/websites.

Written communication has great significance in today’s business world. It is an innovative activity of the mind. Effective written communication is essential for preparing worthy promotional materials for business development. The speech came before writing. But writing is more unique and formal than speech. Effective writing involves the careful choice of words, their organization in the correct order in sentences formation as well as the cohesive composition of sentences. Also, writing is more valid and reliable than speech. But while speech is spontaneous, writing causes delay and takes time as feedback is not immediate.



Advantages of Written Communication

In order that it may be used as and when needed for references and providing permanency of record, written communication is preferred as it is the most effective method of communication.

Written communication is an excellent way of transmitting information across the organizational level. The documents that contain the rules and regulations and procedures or the policy manuals are the example of written communication. Besides, the written communication, through email or memos or in the form of letters, is used whenever the superiors need to advise or instruct their subordinates to carry out particular tasks.

Employees need to be well informed about the policies and the procedures of the organization, so that they may act accordingly. The written communication through policy manual and procedure are written on the related documents, such as loan application form, leave application form, etc., serve the purpose.

Written communication serves as evidence of the events or the actions that have been taken. Also, there are situations that call for the letters or memos on whose basis certain actions are to be taken. In this way, written communication is of great importance to clear the discrepancies. Aside from these, whenever there is a need to convey the important and urgent message to various persons in the organization, written communication may be of great help and assistance providing the required information, which can save the time and effort to be taken to conduct a meeting for that particular purpose. This way written communication provides permanency of records as well.



  • Written communication helps in laying down apparent principles, policies, and rules for running of an organization.

  • It is a permanent means of communication. Thus, it is useful where record maintenance is required.

  • It assists in the proper delegation of responsibilities. While in case of oral communication, it is impossible to fix and delegate responsibilities on the grounds of speech as it can be taken back by the speaker or he may refuse to acknowledge.

  • Written communication is more precise and explicit.

  • Effective written communication develops and enhances an organization’s image.

  • It provides ready records and references.

  • Legal defenses can depend upon written communication as it provides valid records.


Disadvantages of Written Communication

  • Written communication does not save upon the costs. It costs huge in terms of stationery and the manpower employed in writing/typing and delivering letters.

  • Also, if the receivers of the written message are separated by distance and if they need to clear their doubts, the response is not spontaneous.

  • Written communication is time-consuming as the feedback is not immediate. The encoding and sending of the message take time.

  • Effective written communication requires great skills and competencies in language and vocabulary use. Poor writing skills and quality have a negative impact on an organization’s reputation.

  • Too much paperwork and e-mails burden are involved.

What is better oral communication or written

communication?

Both are equally important. It depends on factors effecting communication.

There are three things you need to take into account:


1.    What is the communicator comfortable with?
2.    What is the recipient comfortable with?
3.    What is the outcome you want?


1. What the communicator is comfortable with
There are very few like Churchill who is both powerful writers and speakers.
The creator's natural bent of mind could lean either way. If he plays to his strengths, he is far more likely to communicate effectively. 

2. What the recipient is comfortable with
Effectiveness depends to a large extent on the recipients, and their learning styles. Speaking eloquently and persuasively can have little effect on someone who is a visual learner (either through images or the written word). Writing a nuanced, moving piece on what you want to convey would have no impact on someone who cannot, or doesn't want to, read.

3. The intended outcome
The most important question you have to ask yourself is, What do you want to be effective for? 


·         If you want to communicate facts or complex ideas, writing is usually better. The written word allows the reader to move at their own pace, or back and forth as the need arises, to clarify the topic.

·         If you want to rouse emotion or inspire action, then a good bit of oratory is what you need.


Effective Business Correspondence :Basic Principles

  Place the Reader First
  Keep to the point
  Set  the right tone
  Write a strong opening
  Write a strong close

Thursday, September 12, 2019

What is DNS Records? - Definition from Codetextpro

10:06 PM 0
What is DNS Records? - Definition from Codetextpro

What is DNS Records?


What are DNS Records?


DNS records or Zone files are used for mapping URLs to an IPs. Located on servers called the DNS servers, these records are typically the connection of your website with the outside world. Requests for your website are forwarded to your DNS servers and then get pointed to the WebServers that serve the website or to Email servers that handle the incoming email.


Different Types of DNS Records With Syntax and Examples
Types of DNS Records/ DNS records types
DNS zone types
A
AAAA
CNAME
MX
PTR
NS
SOA
SRV

The above DNS records are mostly used in all DNS Configurations. Now we will see each one with examples.

A Record

An A record or address record.

Address Record assigns an IP address to a domain or subdomain name. When the domain name system was designed it was recommended that no two A records refer to the same IP address.
Suppose you have some domain.TLD domain and want to assign 10.10.0.1 IP address to your web server, then you should create an A record with "www.somedomain.tld" as Fully Qualified Domain Name and "10.10.0.1" in the Value field.

From now on, all the requests for www.somedomain.tld will be sent to a server with that IP.

Basically is useful to use an A record when you have subdomains residing on various systems.

Useful tip: you might use a "*.somedomain.TLD" A record to allow WHATEVER.somedomain.tld to be resolved to your IP, though a wildcard CNAME record is often better than a wildcard A record.


Example of A Record with Syntax

example.com. IN A 69.9.64.11




Where

IN indicates Internet

A indicates the Address record.

The above example indicates that the IP Address for the domain example.com is 69.9.64.11

AAAA Record

An AAAA record or IPv6 address record maps a hostname to a 128-bit IPv6 address.

The regular DNS Address resource record is defined for a 32-bit IPv4 address, so a new one was created to allow a domain name to be associated with a 128-bit IPv6 address. The four “A”s (“AAAA”) are a mnemonic to indicate that the IPv6 address is four times the size of the IPv4 address. The AAAA record is structured in very much the same way as the A record in both binary and master file formats; it is just much larger. The DNS resource record Type value for AAAA is 28.

Example of AAAA Record with Syntax

The AAAA record is to help transition and coexistence between IPv4 and IPv6 networks.An IPv4 nameserver can provide IPv6 addresses:

linux aaaa 3ffe:1900:4545:2:02d0:09ff:fef7:6d2c

CNAME Record

A CNAME record or canonical name record makes one domain name an alias of another. The aliased domain gets all the subdomains and DNS records of the original.

You should use a CNAME record whenever you want to associate a new subdomain to an already existing A record; i.e. you can make "www.somedomain.tld" to "somedomain.tld", which should already have been assigned an IP with an A record.

This allows you to have as many subdomains as you wish without having to specify the IP for every record. Use a CNAME if you have more services pointing to the same IP. This way you will have to update only one record in the convenience of a change of IP address.

Example of a CNAME record: "stuff.everybox.com CNAME www.everybox.com" where 'www.everybox.com' is an A record listing an IP address, and 'stuff.everybox.com' points to 'www.everybox.com'. It will NOT allow you to forward a domain to a specific web page. Use a webshop for that. Port numbers can be changed with webshops, as well; CNAMEs cannot change the HTTP default of 80 to any other port number.

Do not use CNAME defined hostnames in MX records. For example, this is not recommended

Example Of CNAME With syntax
mail.example.com IN CNAME mail.example.net

where

IN indicates Internet

CNAME indicates a CNAME record.

MX Record

An MX record or mail exchange record maps a domain name to a list of mail exchange servers for that domain.

Example with MX Record Syntax - Single mail servers

mydomain.com. 14400 IN MX 0 mydomain.com.

The MX record shows that all emails @ mydomain.com should be routed to the mail server at mydomain.com. The DNS record shows that mydomain.com is located at 26.34.9.14. This means that email meant for test@mydomain.com will be routed to the email server at 26.34.9.14. This finishes the task of the MX record. The email server on that server then takes over, collects the email and then proceeds to distribute it to the user ``test''.

It is important that there be a dot(``.'') after the domain name in the MX record. If the dot is absent, it routes to ``mydomain.com.mydomain.com''. The number 0, indicates Preferance number. Mail is always routed to the server which has the lowest Preference number. If there is only one mail server, it is safe to mark it 0.

Using Multiple mail servers

If you want to use multiple mail servers you have to use MX record preferences. The MX record preference values indicate which mail server to use and in which order to try them when they fail or don't respond. A larger preference number is less preferred. Thus, a mail exchanger with a preference of zero (0) is always preferred over all other mail exchangers. Setting preference values to equal numbers makes mail servers equally preferred.




Example with MX Record Syntax - Multiple mail servers

mydomain.com. 14400 IN MX 0 mydomain.com.
mydomain.com. 14400 IN MX 30 server2.mydomain.com

You can have unlimited MX entries for Fallback or backup purpose. If all the MX records are equal Preference numbers, the client simply attempts all equal Preference servers in random order, and then goes to MX record with the next highest Preference number.



PTR Record

A PTR record or pointer record maps an IPv4 address to the canonical name for that host. Setting up a PTR record for a hostname in the in-addr. arpa domain that corresponds to an IP address implements reverse DNS lookup for that address. For example www.name.net has the IP address 122.0.3.16, but a PTR record maps 16.3.0.122.in-addr.arpa.


Example of PTR Record with syntax

16.3.0.122.in-addr.arpa. IN PTR name.net

Here as you see the IP Address is reversed and added within-addr.arpa and this has come to the left side while the actual domain name has gone to the right side of IN PTR.

This is mostly used as a security and an anti-spam measure wherein most of the webservers or the email servers do a reverse DNS lookup to check if the host is actually coming from where it claims to come from. It is always advisable to have a proper reverse DNS record (PTR) is been setup for your servers especially when you are running a mail / SMTP server.


NS Record

An NS record or name server record maps a domain name to a list of DNS servers authoritative for that domain. Delegations depend on NS records.

NS Record Name Server Record which indicates the Authoritative Name Servers for a particular Domain. The NS records of the Authoritative Name Server for any given Domain will be listed on the Parent Server. These are called the Delegation Records as these records on the Parent Server indicates the delegation of the domain to the Authoritative servers.

The NS record will also be listed in the Zone records of the Authoritative Name Server itself. These records are called as the Authoritative Records.


The NS records found on the Parent Server should match the NS records on the Authoritative Server as well. However, you can have NS records listed on the Authoritative server that is not listed in the Parent Server. This arrangement is normally used to configure Stealth Name Servers.

Example of NS Record With syntax
example.com. IN NS ns1.live.secure.com.

where

IN indicates the Internet

NS indicates the type of record which Name Server record

The above indicates that the ns1.live.secure.com is the authoritative server for the domain example.com


SOA Record

An SOA record or start of authority record specifies the DNS server providing authoritative information about an Internet domain, the email of the domain administrator, the domain serial number, and several timers relating to refreshing the zone.

An SOA(State of Authority) Record is the most essential part of a Zone file. The SOA record is a way for the Domain Administrator to give out simple information about the domain like, how often it is updated when it was last updated when to check back for more info, what is the admins' email address and so on. A Zone file can contain only one SOA Record.

A properly optimized and updated SOA record can reduce bandwidth between nameservers, increase the speed of website access and ensure the site is alive even when the primary DNS server is down.



Example of SOA Record with syntax

Here is the SOA record. Notice the starting bracket ``(``. This has to be on the same line, otherwise, the record gets broken.

; name TTL class rr Nameserver email-address
mydomain.com. 14400 IN SOA ns.mynameserver.com. root.ns.mynameserver.com. (
2004123001; Serial number
86000; Refresh rate in seconds
7200; Update Retry in seconds
3600000; Expiry in seconds
600; minimum in seconds )

name - mydomain.com is the main name in this zone.

TTL - 14400 - TTL defines the duration in seconds that the record may be cached by client-side programs. If it is set as 0, it indicates that the record should not be cached. The range is defined to be between 0 to 2147483647 (close to 68 years !).
Class - IN - The class shows the type of record. IN equates to the Internet. Other options are all historic. So as long as your DNS is on the Internet or Intranet, you must use IN.
Nameserver - ns.nameserver.com. - The nameserver is the server which holds the zone files. It can be either an external server in which case, the entire domain name must be specified followed by a dot. In case it is defined in this zone file, then it can be written as ``ns''.
Email address - root.ns.nameserver.com. - This is the email of the domain name administrator. Now, this is really confusing, because people expect an @ to be in an email address. However, in this case, email is sent to root@ns.nameserver.com but written as root.ns.nameserver.com. And yes, remember to put the dot behind the domain name.

Serial number - 2004123001 - This is a sort of a revision numbering system to show the changes made to the DNS Zone. This number has to increment, whenever any change is made to the Zone file. The standard convention is to use the date of update YYYYMMDDnn, where nn is a revision number in case more than one updates are done in a day. So if the first update was done today would be 2005301200 and second update would be 2005301201.
Refresh - 86000 - This is time(in seconds) when the slave DNS server will refresh from the master. This value represents how often a secondary will poll the primary server to see if the serial number for the zone has increased (so it knows to request a new copy of the data for the zone). It can be written as ``23h88M'' indicating 23 hours and 88 minutes. If you have a regular Internet server, you can keep it between 6 to 24 hours.

Retry - 7200 - Now assume that a slave tried to contact the master server and failed to contact it because it was down. The Retry value (time in seconds) will tell it when to get back. This value is not very important and can be a fraction of the refresh value.

Expiry - 3600000 - This is the time (in seconds) that a slave server will keep a cached zone file as valid if it can't contact the primary server. If this value were set to say 2 weeks ( in seconds), what it means is that a slave would still be able to give out domain information from its cached zone file for 2 weeks, without anyone knowing the difference. The recommended value is between 2 to 4 weeks.
Minimum - 600 - This is the default time(in seconds) that the slave servers should cache the Zone file. This is the most important time field in the SOA Record. If your DNS information keeps changing, keep it down to a day or less. Otherwise, if your DNS record doesn't change regularly, step it up between 1 to 5 days. The benefit of keeping this value high is that your website speeds increase drastically as a result of reduced lookups. Caching servers around the globe would cache your records and this improves site performance.


SRV Record

The theory behind SRV is that given a known domain name e.g. example.com, a given service e.g. web (Http) which runs on TCP in this case, a DNS query may be issued to find the hostname that provides such on behalf of the domain - and which may or may not be within the domain.
Example of SRV Record with syntax
srvce.prot.name TTL class rr pri weight port target
_http._tcp.example.com. IN SRV 0 5 80 www.example.com.

srvce

Defines the symbolic service name (see IANA port-numbers) prepended with a '_' (underscore). Case insensitive. Common values are:

_http - web service
_ftp - file transfer service
_ldap - LDAP service

prot

Defines the protocol name (see IANA service-names) prepended with a '_' (underscore). Case insensitive. Common values are

_tcp - TCP protocol
_udp - UDP protocol

name

Incomprehensible description in RFC 2782. Leaving the entry blank (without a dot) will substitute the current zone root (the $ORIGIN), or you can explicitly add it as in the above _http._tcp.example.com. (with a dot).

TTL

Standard TTL parameter. For more information about TTL values.



pri

The relative Priority of this service (range 0 - 65535). Lowest is the highest priority.

weight

Used when more than one service with the same priority. A 16-bit unsigned integer in the range 0 - 65535. The value 0 indicates no weighting should be applied. If the weight is 1 or greater it is a relative number in which the highest is most frequently delivered i.e. given two SRV records both with Priority = 0, one with weight = 1 the other weight = 6, the one with weight 6 will have its RR delivered the first 6 times out of 7 by the name server.

port

Normally the port number assigned to the symbolic service but does this is not a requirement e.g. it is permissible to define an _http service with a port number of 8100 rather than the more normal port 80.

target
The name of the host that will provide this service. Does not have to be in the same zone (domain). 






Sunday, September 8, 2019

Metering Modes Help How Your Camera Meter Works

7:25 AM 0
Metering Modes Help How Your Camera Meter Works

Camera metering determines the correct shutter speed and aperture should be, depending on the amount of light that goes into the camera and the sensitivity of the sensor.

The most common metering modes in digital cameras today are-

1. Matrix Metering ( Nikon), also known as Evaluative Metering (Canon)
2. Center-weighted Metering
3. Spot Metering 

Some Canon EOS models also offer "Partial Metering", which is similar to Spot Metering.

camera metering modes explained





Matrix (Nikon)/ Evaluative(Canon) Metering:-

Matrix Metering or Evaluative Metering mode is the default metering mode on most DSLR. It works by dividing the entire frame into multiple "zones", which are then all analyzed on an individual basis for light and dark tones. One of the key factors that affect matrix metering is where the camera focus point is set to. The metering system looks at where we focused on the frame and marks it more important than all other zones.

We should use this mode for most of the Landscape photography.





Center-weighted Metering

Center-weighted Metering evaluates the light in the middle of the frame and its surroundings and ignores the corners. Compared to Matrix Metering, Center-weighted Metering does not look at the focus point we select and only evaluates the middle area of the image Use this mode when we want the" camera to the middle of the frame, which works great for close-up portraits and relatively large subjects that are in the middle of the frame.





Spot Metering

Spot Metering only evaluates the light around we focus point and ignores everything else. It
evaluates a single zone/cell and calculates exposure based on that single area.

This mode can use for Wildlife photography.