Showing posts with label Internet. Show all posts
Showing posts with label Internet. Show all posts

DHCP

The Dynamic Host Configuration Protocol is used by computers for requesting Internet Protocol parameters, such as an IP address from a network server. The protocol operates based on the client-server model. DHCP is very common in all modern networks ranging in size from home networks to large campus networks and regional Internet service provider networks. Most residential network routers receive a globally unique IP address within the provider network. Within a local network, DHCP assigns a local IP address to devices connected to the local network.

When a computer or other networked device connects to a network, its DHCP client software in the operating system sends a broadcast query requesting necessary information. Any DHCP server on the network may service the request. The DHCP server manages a pool of IP addresses and information about client configuration parameters such as default gateway, domain name, the name servers, and time servers. On receiving a request, the server may respond with specific information for each client, as previously configured by an administrator, or with a specific address and any other information valid for the entire network, and the time period for which the allocation (lease) is valid. A host typically queries for this information immediately after booting, and periodically thereafter before the expiration of the information. When an assignment is refreshed by the client computer, it initially requests the same parameter values, but may be assigned a new address from the server, based on the assignment policies set by administrators.

On large networks that consist of multiple links, a single DHCP server may service the entire network when aided by DHCP relay agents located on the interconnecting routers. Such agents relay messages between DHCP clients and DHCP servers located on different subnets.

Depending on implementation, the DHCP server may have three methods of allocating IP-addresses:
·    Dynamic allocation:  A network administrator reserves a range of IP addresses for DHCP, and each client computer on the LAN is configured to request an IP address from the DHCP server during network initialization. The request-and-grant process uses a lease concept with a controllable time period, allowing the DHCP server to reclaim (and then reallocate) IP addresses that are not renewed.
·   Automatic allocation: The DHCP server permanently assigns an IP address to a requesting client from the range defined by the administrator. This is like dynamic allocation, but the DHCP server keeps a table of past IP address assignments, so that it can preferentially assign to a client the same IP address that the client previously had.
·       Static allocation: The DHCP server allocates an IP address based on a preconfigured mapping to each client's MAC address. This feature is variously called static DHCP assignment by DD-WRT, fixed-address by the dhcpd documentation, address reservation by Netgear, DHCP reservation or static DHCP by Cisco and Linksys, and IP address reservation or MAC/IP address binding by various other router manufacturers.

DHCP is used for Internet Protocol version 4 (IPv4), as well as IPv6. While both versions serve the same purpose, the details of the protocol for IPv4 and IPv6 are sufficiently different that they may be considered separate protocols.

HLR , VLR


A Home Location Register (HLR) is a database of user (subscriber) information, i.e., customer profiles, used in mobile (cellular) networks. It is a key component of mobile networks such as GSM, TDMA, and CDMA networks. A HLR contains user information such as account information, account status, user preferences, features subscribed to by the user, user’s current location, etc. The data stored in HLRs for the different types of networks is similar but does differ in some details.
 
HLRs are used by the Mobile Switching Centers (MSCs) to originate and deliver arriving mobile calls.
 
A Visiting Location Register (VLR) is a database, similar to a HLR, which is used by the mobile network to temporarily held profiles of roaming users. This VLR data is based on the user information retrieved from a HLR. MSCs use a VLR to handle roaming users.
 
How HLR & VLR are used
Each mobile network has its own HLRs and VLRs. When a MSC detects a mobile user’s presence in the area covered by its network, it first checks a database to determine if the user is in his/her home area or is roaming, i.e., the user is a visitor.
·         User in Home Area: HLR has the necessary information for initiating, terminating, or receiving a call.
·         User is Roaming: VLR contacts the user’s HLR to get the necessary information to set up a temporary user profile.
 
The user’s location is recorded in the HLR, and in case the user is roaming, it is also recorded in the VLR.
 
In case the user wants to make a call:
·         User in Home Area: MSC contacts the HLR prior to setting up the call.
·         User is Roaming: MSC contacts the VLR prior to setting up the call.
 
In case there is a call for the user (call goes to the home MSC):
·         User in Home Area: Home MSC delivers the call immediately.
·         User is Roaming: Home MSC contacts the VLR to determine the appropriate switch in the roaming area to handle the arriving call and then transfers the call to the roaming area MSC.
 
Issues with HLRs:
·      Slow Performance, due to lookups.
·     Questionable adaptability in handling different types of networks, including 3G networks.
·         Limited capability/data to support user authentication.
·         Limited Support for data backups, fault tolerance, and reliability.
·         Scalability.

7 Best things about Internet


Entertainment – You can listen to unlimited music, watch movies or read emails send out by your friends. You will never get bored if you have internet access and will be always preoccupied with lot of stuffs to do.

Savings – Online investments can be done easily with the help of internet. Investments like mutual funds, life insurance policy, online trading in shares / stock market, openings a fix deposit account or a savings account.

Communicate – Communication between friends, family or relatives through emails, social networking sites can be done easily. Also you can put across your views and opinions to the whole world and discuss with them effectively.

Shopping – Internet is used to purchase and sell all kinds of stuffs online. Great and fabulous offers are available online which can help you save few bucks and also can provide you with extra goodies.

Online Banking – Internet users can open savings, current, demat account easily and also access the same through net banking. Online fund transfer, Fixed Deposit and applying for a new cheque book request can be raised with help on internet.

Social Networking – World seems smaller and closer due to availability of social networking sites. You are now closer to your old friends and family members through social websites like Facebook, Twitter and Google+.

Start your own Business – Internet provides numerous opportunities to start up your own business online. You can start with a simple blog, online retail store, buying or selling of products, consultation, online surveys, data entry jobs and marketing of products. Online business requires less capital and no infrastructure as compared to other types of businesses.

7 Best things about Social Networking


Making New Friends – Social Networking helps in reconnecting with your friends and also making new friends. Many of us have found our old school or college friends through social networking sites which was not possible earlier.

Reduced Barrier – Social Networking sites have helped us in reducing communication barrier between friends, families and relatives. We can now share or express our views to anyone easily and freely.

New Business Opportunities – Social networking sites are loaded with Business services and provide good opportunities for earnings. Social Networking sites like Facebook and Twitter have understood the benefits and started linking their sites providing business services like advertising and Marketing.

Express Yourself – You can express your views and opinion on any topic like politics, news, movie, sports freely and also get feedback on the same through social networking. With the help social networking you are updated with current news and affairs around the world 24/7.

Birthday / Anniversary Reminders – Now it is easy to remember birthdays and anniversary dates of your friends, families and relatives with help social network sites. So you will have less complains now and will never miss an important date.

Building new Contacts – Social Networking sites like LinkedIn helps is establishing and creating new business contacts. People of same business domain or profession can share, communicate and discuss on similiar thoughts within the same group easily.

Invitations – Best and the most liked option by me. You can send invitations to your friends and relatives easily without waiting for days for courier or postal services to deliver it for you. You can even alert your friends well in advance and block their calendar’s.

7 Best things about Blogging


Knowledge –Blogging helps you to gain and share knowledge. There are various types of blogs available on the internet. Blogs like fashion, technology, communication, education, movies, health etc are available easily and freely on the web.

Improves Writing Skills – Writing blogs will help you in practicing and improving your writing skills. You are able to improve your writing skills if you are a regular blogger and writing blogs on a continuous basis.

Monetize – Earn money while you blog, you would see this on the internet on various pages or sites. Yes, it is very easy to earn money if you are niche blogger through different sources like being a publisher, affiliate or writing blogs for others.

Hobby – Writing blogs can be a hobby and you can share your thoughts, feelings, views to the world easily without any additional investment. You can start your own blog free of charge and share your thoughts to the world.

New Contacts / Friends – New contacts, friends can be made through blogs. There are lots of meets organized by different blogging communities like indiblogger where you can meet people of your kind, share thoughts, make new friends and have fun.

Getting Famous – People around the world now knows you better because of your blog. Your blog can make you famous and noticeable to the world.

Get Solution / Provide Solution – You can get solutions or provide solutions on any topic which you require or desire information on. Internet is loaded with all types of solutions and provides solutions for your queries.

How to increase traffic on your blog


How can I increase my blog traffic, many of us have these questions and looking out for answers. Here are few ways by which you can increase your traffic.

 
1.      Post regularly - At least twice a day, to keep your readers happy and updated

2.      Keywords - Use keywords by which users can find your site easily

3.      Add Blog to Social Media - Connect your blog to Facebook or Twitter. This will help in gaining traffic and more readers.

4.      Comment on other blogs - Get noticed by readers and other bloggers

5.      Get yourself registered on Twitterfeed and it will ensure Facebook and Twitter are updated with your new updates

6.      Fire up the search engines or ping your sites through Pingomatic or Pinggoat.

7.      Encourage your readers to subscribe to RSS - Feedburner is the best option

8.      Submit your blog to blog directories like Technorati, Techmeme, Blogcatalog

9.      Have Patience - Don't get dishearten if your traffic is low, as it takes time to gain popularity and increase traffic.

Since you have already got into blogging and wish to be a blogger, have patience and take it slow. Even a building is constructed slowly step by step. So don't try to rush and be impatient. All the best.

7 Best things about Blogger


Free Service – A new blogger can start immediately with its own blog without any fee payment or deposits. Blogger hosting is a free service provided by Google.

Easy to Use – User friendly and easy to use interface making it very convenient for a blogger to use from start to the finish.

Templates – Free and paid varieties of templates are available on the web as per your choice and convenience. Google also provides with basic custom templates which very good to use.

Reliable Hosting – Since blogger service is provided by Google, you will never find your blog is down or slow. Great advantage and benefit for blogger users.

Earn while you Blog – Blogger allows user to insert and monetize from their blogs. User can use different types and sizes of ads available in the market and earn money definitely.

Managed by Google – Since Blogger is owned and managed by Google, your site will be index quickly and will reflect in search engines by default.

No Hacking Problem – You can be assured and relax that your site will never be hacked as it is managed and monitored by Google regularly. Since your blogger account linked with your email id, it is impossible for anyone to hack it unless you have shared your user credentials with someone.

7 best things about having your own website

You own brand: Your own website will help you to create your own image and in representing yourself to the world in your own way. Your friends and family can know you better through your website. You can share and discuss about your hobbies, art, pictures, likes and dislikes.

24 / 7 reachable: Friends and family can reach you at anytime, from anywhere through online / website portal. Customers can buy product from your website on weekends or holidays and you don’t need to be online all the time. You can earn while you are sleeping.

Making Money: Making money through your own website is easy and convenient. There is no limit on earnings through your own website as you don’t have to do any huge investments and buy infrastructure. You are the sole owner and don’t have to depend or share your profits with anyone. You can buy a website of your own at $10 per month and start your business. You can also sell space for advertisement to other websites or product sellers.

Blog: Through blogs you can be in touch with your clients and update on new products or queries. Blog helps you to be in touch with them and communicate with them on regular basis. Blogs have grown popularity over past few years and helps in improving business. More blogs means, more traffic on your website.

Save on Advertising Cost: By having your own website, you can save a lot of money on advertisement. No need to go for large printing ads, on the web you can post your ad and reach million customers through your website. You can also advertise on other websites and market your products are very cheap rates.

Each to reach your clients: You can reach and make your own customers through your web portal. Personalized services can be provided to these customers and improve interactions with them will help in increase your business and customer satisfaction.