Fiber optics or optical fibers are made of pure glass which has about the diameter of a human hair. They are bundled into optical cables which can transmit light signals and can contain hundreds up to thousands of fibers. The bundles are wrapped in an outer covering or jacket.

Single-Mode or Unimode Fibers (SMF)

• small core that transmits a single ray of infrared laser light
• Fiber Optics Equipment is more expensive than multi-mode
• Better at retaining the fidelity and accuracy of each light pulse over long distances
• Preferred method in scientific research such as medical or mechanical imaging

Multi-Mode Fibers

• larger core transmitting infrared light generated by LED’s
• Lower-cost than the more expensive laser resources and equipment required for SMF
• Traditionally used for short distance communication such as within a building or campus

Plastic Fiber

• core can be 100 times larger than glass fiber and connectors as well as installation are  less expensive than glass fiber
• Traditionally used for low-speed, short-distance (<= 100m) networks

Fiber Optics Basics

In  optical fiber or fiber optic cable the light travels through the core by constantly bouncing along the cladding which is like a mirror-lined wall.

We all know that light travels in a straight line, so when you shine a flashlight beam down the hall it won’t illuminate what is around the corner. You could however place a mirror at the end of the hallway so the light beam would bounce of and reflect around the corner.

You might repeat this process by placing multiple mirrors at various corners and the light beam would just propagate. This is exactly what the cladding does in optical fiber.

Just as electrical signals though there is some degradation in light signal the further it travels. This is mostly because of impurities in the glass and the wavelength of the transmitted light. To compensate for this signal loss or degradation an optical regenerator is often spliced along the cable to boost the signal.

By using a special coating on a portion of optical fibers (Doping) the light that hits the doped coating is pumped with a laser beam that amplifies the signal.

Fiber Optics Broadband

Very-high-bit-rate Digital Subscriber (VDSL) uses fiber-optics to deliver Internet access to your home or business.

This can be achieved through Fiber to the Node (FTTN) or Local Exchange, Fiber to the Cabinet or Curb (FTTC), Fiber to the Building (FTTB) or for maximum speed Fiber to the home (FTTH).

In the case of FTTC the fiber runs all the way from the local telephony exchange to the street cabinet containing a DSLAM. From there on the signal is carried on to your house over metallic or copper wiring.

Suffice to say that the shorter the copper wire length, the higher the signal throughput. That is why FTTH is the fastest connection as there is no copper wire involved.

As mentioned before, FTTN means the fiber is terminated at the local Exchange while FTTC extends the fiber connection to a cabinet – containing a DSLAM – closer to your home or business before sending the signal over a copper wire.

http://computer.howstuffworks.com/fiber-optic.htm

The post Fiber Optics Communication System appeared first on pcuserinfo.com.

• Comparison of destination MAC address and bridge table addresses
• If unknown source address, new entry in MAC address table with source port gets created
• If destination MAC address from same segment as source, no forwarding (Filtering)
• If destination MAC address from different segment as source, forwarding
• If destination MAC address unknown, broadcast to all devices except receiving port (Flooding)

A LAN ethernet switch is essentially a multiport bridge that use microsegmentation to reduce the number of collisions in a LAN and increases the available bandwidth.
In addition to faster microprocessors and memory, two other technological advances made ethernet switches possible.

Content Addressable Memory (CAM) allows an ethernet switch to directly find a port associated with a MAC address without using search algorithms.

An Application-Specific Integrated Circuit (ASIC) is a device consisting of undedicated logic gates that can be programmed to perform functions at logic speeds. Operations that might have been done in software now can be done in hardware using ASIC.

Another function of a LAN ethernet switch that dramatically improves bandwidth is full-duplex transmission.

• Doubles the amount of bandwidth between nodes
• Provides a collision-free transmission environment

Microsegmentation facilitates the creation of a dedicated segment and provides dedicated bandwidth to each user on the network. It reduces collisions in a network and efficiently increases the capacity for each station connected to the network.

Ethernet Switch Latency (Propagation Delay)

Caused by

• Media delays
• Circuit delays
• Software delays

Delays caused by the content of the frame and where in the frame switching decisions can be made. For example, a device cannot route a frame to a destination until the destination MAC address has been read.

Latency is the time delay between when a frame first starts to leave the source device and when the first part of the frame reaches its destination.

Ethernet Switch Modes

• Store-and-forward – switch reads entire frame, checks for errors and sends. If errors are detected, frame is discarded. Must be used for asymmetric switching
• Cut-through – switch reads frame up to the destination MAC address, then sends, no error-checking
• Fragment-free – Reads initial 64 bytes where most errors and all collisions occur, before forwarding

Spanning-Tree Protocol

An ethernet switch sends special messages called bridge protocol data units (BPDU) out all its ports to let other switches know of its existence. The switches use a spanning tree algorithm (STA) to resolve an shut down the redundant paths in order to avoid loops and cause Broadcast storms.
Consequently switches have five operating modes

• Blocking – Port sends and listens to BPDUs but does not forward frames. Default state of all ports when switch is powered on
• Listening – Port listens to BPDUs to make sure there are no loops on the network, no frames are forwarded
• Learning – Port learns MAC addresses and builds an address table, no frames are forwarded
• Forwarding – Port forwards frames, BPDUs are sent and listened to
• Disabled – Port does not participate in the operation of STP. No listening to BPDUs or forwarding. Port is in “shutdown” state

Collision Domains and Broadcasts

Layer 1 media topologies

• Shared-media environment – Multiple hosts attached to the same medium. Traditional bus-based (coax) Ethernet and hub-based Ethernet (UTP)
• Extended shared-media environment – By using repeaters or multiple hubs, creates an extended collision domain
• Point-to-point network environment – Widely used in dialup networking, one device connected to only one other device. No collisions

Layer 1 devices do not break up collision domains. Layer 2 and 3 devices do brake up collision domains, also known as segmentation. Segmentation increases the amount of bandwidth in the collision domain. This works well as long as the traffic between segments is not too heavy. Otherwise the Layer 2 device could become a bottleneck itself.
Layer 2 Broadcasts

Layer 2 devices such as an ethernet switch must flood all broadcast (0xFFFFFFFFFFFF) and multicast traffic because they cannot learn the broadcast or multicast MAC address. The accumulation of broadcast and multicast traffic is referred to as broadcast radiation. Because the NIC must interrupt the CPU to process each broadcast or multicast group that it belongs to, broadcast radiation affects the performance of hosts in the network.

Workstations broadcast an Address Resolution Protocol (ARP) request every time they need to locate a MAC address that is not in the ARP. The three sources of broadcasts and multicasts in IP networks are workstations, routers, and multicast applications.

Broadcast storms can be caused by a device requesting information from a network that has grown too large.

So many responses are sent to the original request that the device cannot process them, or the first request triggers similar requests from other devices that effectively block normal traffic flow on the network.

A flat-switched network is a network of interconnected switches that does not utilize Layer 3 routing or something similar.

A particular video application can generate a 7-megabyte stream of multicast data that, in a switched network, would be sent to every segment, resulting in severe congestion.
Broadcast Domains

A broadcast domain is a grouping of collision domains that are connected by Layer 2 devices. Broadcast domains are controlled at Layer 3 because routers do not forward broadcasts. For a packet to be forwarded by a router, it must contain an IP address that is outside the range of addresses assigned to the LAN segment.

Data Flow

• Layer 1 device (NIC) – Always forwards frame
• Layer 2 device (Ethernet Switch) – Forwards unless something prevents it
• Layer 3 device (Router) – Does not forward unless it has to

Layer 2 and Layer 3 Switching Combined – Multi Protocol Label Switching (MPLS)

Multi protocol label switching MPLS  is a very flexible and scaleable architecture that basically integrates Layer 2 switching with Layer 3 routing capabilities. It allows for network engineering through the use of labels which are attached to the header of a packet only once.

This greatly reduces the time routers need to perform complex lookups in their routing tables as they forward packets based on the label without further examination of the packet. Mpls is sometimes said to  be operating at the 2.5 layer and is protocol agnostic which means it can transport any kind of data packets including IP, ATM and SONET.

MPLS Ethernet switch labeling allows most packets to be forwarded on the backbone at a layer 2 (switching) rather than a layer 3 (routing) level which explains its faster transfer speed.

http://www.pulsewan.com/data101/mpls.pdf

http://www.youtube.com/watch?v=H7KQcNRgGEk

The post What is an Ethernet Switch and Layer 2 Bridging Explained appeared first on pcuserinfo.com.

Website hosting is a tricky business because you are trusting a hosting server to be the constant cushioning for your site at all times. The web hosting server has a large impact on the way the client website is presented to users.

The loading speed, timing out of sessions and security wormholes all occur because of the webhost and client website’s interaction. What can a small business do when it cannot associate with expensive hosts but does not want to bear the negative effects of a weak server?

CloudFlare is One of the Best Web Hosts for Small Business

CloudFlare is a website and email hosting company that specializes in upgrading the performance of websites and making them more secure against attacks. It meshes your website into and passes your traffic through its community network.

CloudFlare helps speed up web page loading and makes the experience better for visitors who are less likely to leave the site quickly annoyed at slow loading and poor performance.

CloudFlare’s secure website hosting is just what a small business needs. The globally distributed network of the service helps spread out traffic so that the website’s incoming “pipes” don’t get clogged. CloudFlare blocks the entry of all kinds of malicious traffic like resource-wasting bots, crawlers and spiders, targeted attacks, viruses, and spamming sources.

By blocking the bad stuff, traffic influx is reduced to only legitimate visitors and general crawlers. This means your website is not only safe from being compromised, it will be wisely allocating its resources and bandwidth, and the site itself will be efficient and quick to load.

The main features of CloudFlare’s managed website hosting that set it apart from other website hosting providers, and that a small business can benefit from, are:

CDN (Content Delivery Network)

Cloudfare cloud website hosting globally distributes your website content over its network, saving the information at strategic locations. The nearest storage point is accessed whenever a visitor of any part of the world visits the website.
This greatly increases the speed of the downloading of webpage content onto the visitor’s computer since information isn’t being called from the far away home location of the site.

Dedicated Website Hosting Optimizer

Providing optimal performance is another feature of CloudFlare. Even heavy websites that contain a lot of images, advertisements and widgets from third party sources are downloaded swiftly – even on mobile devices! No matter the device you are using,

CloudFlare’s optimizer ensures the quickest website loading through its Rocket Loader feature by reducing network connections. To customize your services, you can very easily toggle an optimizer feature to on or off as per your requirements. Simple, quick and effective!

Business Website Hosting Security

CloudFlare’s security checks and blocking options are great for any website, particularly a small business site. The proxy servers which exist all over the world help enhance the blanket of security over all websites linked with the network and the system becomes stronger and more efficient as the network grows.

If there is an atypical shoot in site traffic, CloudFlare knows to assess for possible attack. By scrutinizing the visitors, the service searches for a familiar pattern that indicates a malicious intention.  About 15 percent of the incoming traffic to a site is of malicious intent – whether of automated design or individual hacker action. CloudFlare blocks spammers, hackers, cyber criminals, DDOS, SQL insertion and so on.

Analytics

CloudFlare provides statistics and analytics regarding your website traffic so that you are kept in the loop. Information regarding how many visitors hit your site, and which are search engine spiders or attack hits, is at your fingertips.

Unlike other analytics programs, CloudFlare analytics lets you monitor spiders from search engines, illegitimate traffic, and security threats; since about 20-50 percent of any website traffic is composed of these sources, this is information you could greatly benefit from.

Applications

CloudFlare requires no extra software or hardware purchase and installation, and no meddling with site code. The actual process of joining the network occurs in a matter of minutes. Likewise, the service also makes it quick and easy to install widgets and apps from the web to your website in a secure manner.

Packages and Plans – Best Website Hosting for Small Business

CloudFlare is offering its main services for new customers completely free. The free plan promises a security setup, enhanced website speed and performance, and the provision of statistics. Your static content will exist on each of the 23 mirror sites that have been set up worldwide and can be quickly loaded from any cache site. Furthermore, security is enforced by options like blocking specific IP or country access to the website, protection of email harvesting or hotlinking security.

There are many shared WordPress website hosting endeavors which partner with CloudFlare and provide their customers a unique shared experience whereby they are able to enjoy CloudFlare services within their original host accounts. This is the ultimate solution for small business owners for hosting their websites as they do not have to invest highly in security options or contact web developers for working on website performance.

Of the many partner hosts, a few notable ones are BlueHost, Hawk Host, VEXXHOST, HostPapa, Media Temple, Bluehost, and A2 Hosting.

The recent feather in CloudFlare’s cap is the initiation of an Optimized Hosting Provider program that adds to the existing Certified Hosting Provider program. CloudFlare’s shared hosting programs are a huge advantage for small business owner websites. The Optimized partners are automatically inducted into the Railgun technology service.

Railgun greatly improves the connection in the network linking the hosting provider and the cache site which is nearest a visitor accessing the website – hosts can now make websites available world over.

Affordable Website Hosting

CloudFlare also offers premium services in its Pro, Business, and Enterprise programs, but the website hosting cost is still very nominal for Pro package. Various higher-level security and performance enhancement features are offered to websites which register.

CloudFlare claims to enhance website performance by causing a reduction in bandwidth usage by up to 60 percent, and reduces incoming traffic by 65 percent – the resulting web page loading time is halved! Plus, your website is more safe and secure than ever.

The post Using CloudFlare To Improve Small Business WebSite Hosting appeared first on pcuserinfo.com.

The first thing every new college student learns is the art of saving money. Cutting costs on a laptop for college becomes a priority when running low on funds and time. Unfortunately, a computer is one of those things that every student needs but few students can actually afford. Don’t rack up more charges on the credit card; look for some wallet-friendly ways to get your tech gear instead.

This guide will share some of the smartest ways to stay connected this semester. Are you ready to whip that budget back into shape? Start with the following five suggestions.

How to Snag an Inexpensive Laptop for College – Look for the 3 “R”s

The three Rs are refurbished, recertified, and “rough condition”. You’ll find the first few terms on most retailer and manufacturer websites.

Refurbished and recertified both refer to laptops that a customer returned after purchase, put up for sale again after the manufacturer restored it to working condition.

Rough condition is a term you’ll find on secondhand auction sites and at pawn shops – if you don’t mind buying used, it’s better to buy an ugly laptop with scratches than a pretty laptop that fails to perform.

Laptop for College – Factor in the Long-Term Costs

Every retailer offers different incentives to lure you in. Instead of comparison shopping based on price alone, try to factor in the added bonuses. Things like warranties can save you thousands of dollars over the years. Two customers looking at the exact same Dell laptops might choose different retailers because one offers free technical support while the other offers free faceplates for customization. Where you shop does make a difference. Prioritize Needed Features

Retailers don’t like to display their most basic goods because they want to highlight the expensive models instead. You have to look for good deals. Opting for a smaller screen and less hard drive space will save you a lot of money. You can always invest in better hardware later, when you have the spare funds.

What is the Best Laptop for College – Buy Broken Goods

Most of the time, buying a broken laptop is a horrible thing – but not when you get the laptop for free or close to it. It is shocking how often laptops are given away for parts, because most of the time it’s just a single broken part that is stopping the computer from working. If you’re lucky, you might be able to fix a free laptop by replacing a $50 computer component. That’s a very inexpensive laptop.

What is a Good Laptop for College – Get Back to the Basics

It’s worth considering the idea that you might not need a laptop at all. Sometimes the price difference between two computers with the exact same performance ratings can differ by thousands of dollars depending on whether you’re dealing with a laptop or a desktop PC. If somebody offered you $1000 up front to write your notes on paper all year, would you do it? You can always transfer those notes to your PC later.

Spending money feels a little better when you know you racked up as much in savings as humanly possible. Saving money feels better when you know you didn’t have to sacrifice the things you need just to pinch pennies. Nothing feels better than being perfectly equipped for college without incurring a mountain of student loan debt.

The post 5 Ways to Save Money on a Laptop for College appeared first on pcuserinfo.com.

First thing to keep in mind when it comes to group policy management is that organizational units are not the same as security groups. The key thing to remember is that a security group is used to assign permissions whereas a OU is just a container of objects.

Take care of properly designing your OU structure by considering the geographical or departmental location and needs of your users.

As you will probably know, OUs most likely contain one or more child OUs which by default inherit security stings from the parent OU.

As usual, no matter the size of your company, try to keep it simple. The concept is very similar to AD design where a single domain in a single forest is the easiest to administer.

Windows 7 Group Policy Management

The same goes for OU structure, try to minimize the amount of OUs  in order to avoid too much complexity. Avoid creating additional administrative overhead by creating multiple OUs that are subject  to the same GPO or security settings.

OUs are designed to make administration more easy. Of course, also do not oversimplify your OU structure as this might very easily override GPO settings required for specific users or computers.

Group Policy Management Console – http://www.microsoft.com/en-us/download/details.aspx?id=21895

What is Group Policy – Group Policy Management Editor

The first thing to keep in mind is that GPOs are either applied to users or computers.

Starter GPOs

Multiple pre-configured GPO settings (3000 +) are available in Windows server 2008 R2. If you are not sure of the template you want just right click on a folder icon in the group policy management editor and choose Filter Options to enter your search criteria.

Multiple local group policy objects (MLGPO)

Whereas in the past, when you applied a local group policy restriction all users including administrators would be affected by the GPO. MLGPO enables you to enforce different GPOs based on the group the user is a member or any individual user account.

Site GPO

• GPO must already exist to link it to a site
• Not very common except to define network settings

Domain Linked GPO

General advice is to leave the default domain policy alone as any changes made to this policy are Doman wide

It is better to create a separate policy and scope and not touch the default domain policy.
Order of Inheritance (Screenshot)

Group Policy Management Scopes

As a rule child Ou settings will take precedence over domain or site settings GPOs There are ways to override this behavior, but they should only be used if all other options are not fit for your strategy.

One way would be to “Block Inheritance” Be very careful with this setting as it will block any other policies from being applied to the OU..
Enoforce GPO Settings will do just the opposite and should also be used sparingly.

Advanced Group Policy Management

Filtering

Very similar to using NTFS permissions.  Go to the properties tab and check the Deny Group Policy Setting. (screenshor) As always DENY overrides any other settings.

You should design the scope of management or inheritance  of your OUs properly and only resort to enforce or block inheritance as a rare exception.

WMI Filters allow you to filter GPOs based on

• Hardware
• Software Deployment

If there is anyone out there using Group Policy to distribute software, read on. Suffice to say that it can be accomplished the MS way.

• Assigned – Software gets installed regardless of user consent
• Published – user has the option to install
• Has to be an msi file

Admx vs adm files

In the old days –Win 2000 and earlier – we used to rely on Adm files, which were language dependent. They got replicated to all the SYSVOL folders in the domain so that every policy that is created also has every adm file connected to it stored in the SYSVOL. There often was an inconsistency between different language versions.

Admx and Adml

Admx files contain universal settings whereas the adml files contain language specific settings. These files can be stored in a central store making them a lot more efficient and less bulky than the adm files which had to be present in every SYSVOL volume in previous versions of Windows Server.

The post Group Policy Management Structuring and Design appeared first on pcuserinfo.com.

When search engines first began the process of locating relevant websites for people searching the internet, things were relatively simple. Most websites were pretty small and didn’t contain very much information. It was easy for the search engines to gather all of the information from a website and store it for use.

However, as websites continued to grow in size and popularity, this task became more difficult. Some business websites contained hundreds or even thousands of pages with links for individual products, and when blogs started becoming popular, websites were being updated daily with new information.

Search engines were forced to skip a lot of the information found on a website in order to continue to provide speedy results for users.

Google XML Sitemap Generator

In 2005, all of that changed when Google started using Sitemap 0.84 Protocol in XML format.

Sitemaps provide a way of organizing all of the data on a website in one location. They identify all of the URLs on the site and list the data found in each section.

While sitemaps did exist prior to 2005, they were geared more towards users, not search engines. The XML sitemap format designed by Google made it possible for the search engines to find data quickly and easily, completely changing the search industry.

Although the XML sitemap system worked great for Google, other search engines such as Yahoo and Bing did not use it. This meant that website programmers needed to create different sitemaps for each search engine. It created more work for programmers and confusion for website owners.

Thankfully, Google published the XML protocol under the Attribution/Share Alike Creative Commons license, allowing other search engines to pick it up as well. Today, website programmers are now able to create one sitemap for all search engines.

If you currently own or plan to own a website, you need to include an XML sitemap so that search engines will be able to locate and organize the data on your site for potential readers or customers.

XML Sitemap Generator

However, you don’t necessarily need a programmer to accomplish this. An XML sitemap generator makes that easy and, very often, completely free. XML sitemap generators take the information on your website and instantly generate two sitemaps for your website–one for search engines, and one for users.

You can then add these URLs to your website and instantly see the benefits of search engine visibility. A simple entry into your robots.txt file will let all search engines know where your sitemap is located so they can begin organizing and storing your website’s data.

It’s important to understand that using an XML sitemap generator to create an XML sitemap for your site does not replace the need for search engine optimization.

XML Sitemap Creator

An XML sitemap generator is simply a tool search engines use to make their searches and rankings more accurate. It is not necessarily going to get you higher rankings. While your traffic may increase a little after adding your XML sitemap, this is only temporary.

To see your website’s rankings and traffic continue to increase, you will need to hire an SEO firm or specialist to continue to fine-tune your website for search visibility and get ahead of your competition.

If you have recently launched your website, or plan to in the near future, use an XML sitemap generator to make it more visible to search engines. The XML sitemap protocol will help the search engines organize the data on your site so it can begin showing up in searches. There are many online XML sitemap generators, and many of them are free to use.

Once your sitemap has been added, continue to work with an SEO specialist so that your ranking and traffic will continue to increase.

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A few months ago, I decided that I would finally start my very own website. I didn’t know much about how to create a website, but luckily I found a free online host that made it very easy. All I had to do was follow the easy instructions within their editing system, and within about an hour, I had published my first website.

In fact, I didn’t begin to run into problems until the system asked me about mobile website design. As it turns out, there was no fee to publish my traditional website, but if I was interested in mobile website design, there was going to be a small monthly fee.

How to Design a Website For Mobile Phones

This of course, got me to asking whether or not I really needed a mobile website design, or if a traditional site was sufficient. In order to try and answer this question, I proceeded to access my site through my cell phone.

Unfortunately, the results were less than ideal. Not only could I not see several areas of my webpage due to the small screen on my cell phone,

I was unable to make a purchase using the traditional site. Right then, I knew that a mobile website design was going to be necessary.

Now that I had determined that I was in fact going to require mobile access to my website, the question was whether or not I would be accomplishing this task through the same server I had been using, or whether I should turn to a professional web designer for these services.

After comparing the monthly fees that were charged by the hosting site to the one time fee of a web designer, it turned out that hiring a professional was actually more cost efficient. While it did require me to make a more substantial initial investment, choosing to hire a professional web designer did not require payments on a monthly basis.

Choosing this option helped me to keep my overhead at a minimum while I was waiting for my site to take off.

Mobile Friendly Website Design

Once my site was mobile friendly, I started to see an increase in sales almost immediately. As it turns out, many of my customers choose to utilize mobile devices to access the internet. When my site was not mobile, these customers were unable to take advantage of my products and services.

Now that my site is easily accessed from any mobile device, the only problem I have is keeping up with the huge amount of orders that have been coming in. So if you are planning on starting a website, and are not really sure whether or not a mobile website design is really necessary, I urge you to take a few minutes to research a few statistics.

Once you learn how many of your customers are using their cell phones and tablets to access the web, you will understand exactly why it is so important for your site to be mobile. After all, customers will typically choose to use the site which is easiest for them to navigate, and the easiest for them to find.

Not only will your site be incredibly difficult, if not impossible to use without a mobile design, your site will also not be listed in the mobile directories. This will prevent your customers from finding you easily, and will often send them looking towards your competitors instead.

A small investment in a mobile design will ensure that your customers are able to find you easily, and utilize your site with a mobile friendly interface.

This will help to increase your profits, and expand your business. Personally, I believe that going mobile was the best thing that I have ever done for my business.

The post Do You Really Need To Utilize Mobile Website Design appeared first on pcuserinfo.com.

Drupal is the excellent technology that is utilized in order to build various websites. It is actually among the most favored modular free open source CMS (Content Management System) framework which adds plenty of importance on collaboration.

The creating and designing of this application is in a way that it has to be tailored or customized as per a particular project’s requirements. However, a restriction of its feature of customization is the fact that, such alterations are done through overriding and/or adding brand new modules into the already existent application.

Drupal is unique and exclusive as it separates the management of the content from the presentation of the content.

Using Drupal

Drupal technology web applications are utilized in order to create any type of web portal, online sites founded on ecommerce, web stores and also corporate websites.

The Drupal software is very dynamic and it can be used in order to build any type of website. A case in point is the fact that Drupal has been utilized also to build online directories as well as e-learning websites.

Drupal Spam and Security

Drupal technology is supported and secured by a booming security team which responds to all threats to keep it safe. Drupal is backed up by an always accessible online community, software developers, designers and site administrator that all work continuously in order to further improve the technology.

Drupal Content Management System technology is utilized not only to build online trading websites, but the software can also be used to successfully build instant messenger, it can be used also to incorporate video and audio facilities into the websites, together with image and photo galleries. The Drupal CMS is totally secure and safe.

The mere fact that Drupal developer technology easily allows the customization or personalization of its sites as per the specific needs of a particular website project makes the software even more special and unique as well as favorite among developers.

Drupal for Windows

The Drupal Content Management System technology is a very search engine friendly system as well that has led to the easy as well as efficient ranking of all the websites that are created with the use of such technology in order to rank good in search engines.

This makes it an excellent choice for marketers of products that are looking to gain some organic search traffic.

The best way in order for you to get the most out of using Drupal technology is to have your website built with this CMS technology by a reliable web solutions firm which has the experience and expertise in this field.

Web designers that are well trained with the Drupal technology can help alter the Drupal templates based on your needs and set your website up in accordance with your very own desire.

The post Getting Acquainted with Drupal Technology appeared first on pcuserinfo.com.

Domain name resolution or domain name to IP resolution in Windows can be achieved by using the NetBIOS Extended User Interface (NETBUI) in combination with WINS as well as DNS.

While the former two methods are a bit outdated and are said to become obsolete, they might still be required for some older legacy applications in your company that require single namespace resolution.

DNS resolves hosts names to IP addresses and contains several new features and enhancements in Windows Server 2008 R2 such as:

Stub Zone Support – A zone that only contains a copy of the authoritative servers for a zone like the SOA and NS records without including all the records for the hosts registered in that zone.

Stub zones in Active Directory are useful to hold records of child domains and therefore delegate authority to that child domain for any records it is responsible for.

These are called Delegation or Glue Records. Likewise, you can use stub zones in the child domain to hold records pointing to the parent domain.
To create a stub zone you must have administrator privileges on the target DNS server.

Domain Name Resolution – Conditional Forwarding

Without a stub zone a DNS server will forward a domain name resolution request to an upstream DNS server if it holds no records for the request in its database. This is called a recursive query as the upstream DNS server will contact other DNS servers if it has no record.

Conditional forwarding in Windows Server 2008 R2 means that you can configure a DNS server to forward queries for a particular domain space to one or more specified DNS servers. If no conditional forwarders are configured or the forwarder is unable to resolve the name the DNS server will fall back on its root hints in its attempt to resolve the name.

For Security purposes it is generally recommended to remove the root hints from a domain controller. If the server would use root hints to perform iterative queries it would be vulnerable to attacks from the Internet. Preferred practice would be to use a caching-only forwarder to perform these queries on the public Internet.

DNS Zone Transfers and Replication

As long as the zone is Active Directory-integrated and the DNS service runs on a domain controller, it is automatically replicated to all DNS servers. These DNS servers must be specified to allow for zone transfer.

Read Only Domain Controllers (RODCs)

RODCs contain a primary read-only zone which can only be updated by pulling new DNS records from a writeable domain controller it has access to.

DNS Security Extension (DNSSEC)

Uses digital signatures and certificates to improve domain name resolution security

DNS Cache Locking

A popular method of malicious servers sending the DNS server a response to write or overwrite an entry in the cache.  Cache poisoning involves overwriting the entries in the cache with entries pointing to the attackers’ server. Windows Server 2008 R2 lets you lock down the cache.

DNS Socket Pool

Allows for a randomized pool of source ports as opposed to the known DNS ports and thus helps in reducing attack attempts.

DNS Devolution

Provides host name resolution for child domains. It will first append the domain namespace of the parent domain and subsequently append the namespace for each child domain to facilitate domain name resolution.

Background Zone Loading

While it could take a long time in large organizations to load the DNS data and start servicing clients Windows Server 2008 R2 remedies this situation through background zone loading. Background Zone Loading in Windows Server 2008 R2 allows the server to respond to domain name resolution queries much faster by using information stored in Active Directory.

GlobalNames DNS Zone

While similar to WINS to resolve hostnames to a single namespace the GlobalNames zone is not supported for peer-to-peer name resolution. Instead the zone holds a CNAME resource record mapping a single-label name to a FQDN, usually belonging to corporate servers or websites.

WINS Push and Pull

As soon as a specified number of updated records have been reached in the WINS database the WINS server will push the updates to its peers.

Pull replication lets an administrator specify to allow updates at specific intervals.

Windows Server 2008 R2 – New DNS Features in Domain Name Resolution

• Background zone loading
• RODC support
• GlobalNames DNS Zone
• Full support for IPv6 forward and reverse lookup

Windows Server 2008 R2 DNS Role – http://technet.microsoft.com/en-us/library/cc753635%28v=ws.10%29

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Many of us have to leave our homes without protection during the day when we’re off to work early in the morning. On the other hand, some people often don’t feel safe leaving their children at home. These problems force us to think about home security camera systems.

Home monitoring is a necessary part of the house because of its repeated use. Although home camera security systems may not prevent or fight an attacker, home security camera systems warn us or help us identify criminals later on.

If you’re not using camera home security systems, the time has come for you to realize some of the inherent benefits of CCTV cameras.

First, you can leave your home with a quiet mind in the morning. Most importantly if you have kids you do not have to worry if the maid will take care of your children properly!

You can be sure that your garage is closed,  taking away the worries you would have without using a home systems security camera . When installing the system you can leave on a long vacation without worrying about the house.

IP Home Security Camera Systems

Sometimes we are afraid to buy home security camera systems, believing that the cameras are made for business purposes only. Well, security systems are available for both the home and commercial use. Some cameras are designed for indoor use.

The newer systems are available with a variety of innovative features. For example, IP-enabled security cameras and motion sensors with a lens are some of the significant progresses made in the field of home security.

The big advantage of buying camera security systems for home  is that you can provide a higher level of security for your property as well as people. You can select from a wide range of things. There are cameras to monitor an area at all times, regardless of any movement.

In addition, systems are triggered by any movement within the protected area. The first type of control system is generally, either permanently or from time to time, depending on the sensitivity of the protected zone.

Ability IP CCTV cameras are more developed than the previous models. The main advantage of this system is that it can be connected via the Internet. Notification is an important feature of this aspect.

This means that you will automatically receive e-mails sent from the security cameras when there is a negative impact within the protected area. This particular aspect has made the system very popular among users.

Wireless Home Security Camera Systems

Security system cameras can be divided between wired and wireless systems. The wireless camera systems include some of the older models. Although relatively new, wireless home security systems have become extremely popular.

However, wired systems are not without value and may serve as a more reliable alternative. Omba owns a store selling security products, check out his store here: http://firstclasssecurity.net/

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