Today's telecommunication arena is rapidly moving towards next-generation networks (NGNs) that offer ubiquitous, converged services over converged voice, video, data and mobile networks. Until very recently, the prevailing telecommunications paradigm was based on multiple types of networks, each serving different types of applications.
While IP-related technology holds the most promise for meeting the requirements of NGNs, the use of the global Internet is quite limiting. The IP Multimedia Subsystem (IMS) is an architecture that allows delivery of identical services to fixed and mobile customers - regardless of whether they are connected through the packet-switched (PS) or circuit-switched (CS) network. IMS-based services enable communication in a variety of modes - including voice, text, location, presence, messaging, pictures and video, or any combination of these.
In addition to service creation and delivery, IMS handles call control issues, and can easily be adapted to serve roaming subscribers. The IMS architecture is inherently capable of bridging between separate networks, and will ultimately be used for all types of networks, such as wireline Voice-over-IP (VoIP) networks, WiMax wireless networks and packet cable networks.
The expansion and acceptance of IMS is an indication of just how important this technology is to the future of unified communications. Many organizations which are responsible for network standardization are currently adopting IMS technology. The ramifications for the industry are significant, and the entire telecommunications industry is gearing up for the imminent widespread implementation of IMS.
Based on a Strong Signaling Foundation: Session Initiation Protocol (SIP)
IMS technology was originally developed for the cellular arena to define how to set up advanced services for 3G cellular networks and grew out of a group of standards created by the 3rd Generation Partnership Project (3GPP).
IMS is a Media-over-IP network and uses the Session Initiation Protocol (SIP), originally standardized by the IETF, as its base signaling protocol. The 3GPP chose SIP as its base protocol because previous telecom signaling protocols failed to comply with all IMS requirements. Because SIP is an Internet protocol, it can accommodate convergence, and has the potential to meet all the needs of the IMS architecture. For instance, SIP can signal between different network entities, including endpoints and servers. In IMS, each network server has its own role, in contrast to traditional networks where a central office switch does it all, including call control and service control. In addition, SIP uses Internet extensibility mechanisms. A service provider with IMS networks initially may only have a small number of subscribers. As the subscriber base grows, IMS networks must be easily scalable to add more subscribers. SIP is also very flexible, and uses standard extensions. SIP's flexibility enables IMS networks to adapt and change signaling protocols to meet dynamic market needs. Finally, SIP provides adequate security, with both internal and external security mechanisms.
IMS SIP: A Complex Challenge
While offering the right foundation, SIP in its IMS form has proven to be quite complex and presented many technological challenges. There were many gaps between the SIP initially defined by the IETF, and the features required for full IMS support. To solve this problem the 3GPP defined dozens of SIP extensions - additions that are specific to IMS networks. Collectively, these extensions comprise the IMS SIP protocol, which is defined in the 3GPP TS.24.229 standard. These extensions, such as extended call control, presence and instant messaging, extend the functionality of SIP on IMS networks. This new IMS SIP usage profile is perhaps the most important in the telecommunications industry, and is uniquely the most appropriate for NGN networks.
To illustrate the inherent complexity of IMS SIP and all its extensions, we will review the major extensions below:
SigComp (RFC 3320)
The SigComp extension defines how to compress SIP textual signaling data, which can be very large and problematic to transmit, causing delay. SigComp solves the challenges of roundtrip delays, as well as mobile user equipment battery life
P-headers (RFCs 3455 and 3325)
(P- Private) In addition to standard headers, the 3GPP defined additional headers targeted at solving specific IMS network problems, such as obtaining information about the access network (cell ID) and the visited network (roamed network), and determining caller identity.
Security Agreement (RFC 3329)
This IMS SIP extension specifies how to negotiate security capabilities for multiple types of endpoints.
AKA-MD5 (RFC 3310)
This IMS SIP extension determines how terminals and networks are authenticated using already defined mechanism (e.g. ISIM), as well as specific key exchange.
IPSec
IPSec is used on various IMS interfaces and between different IMS networks. IMS uses IPSec in the transport mode, as opposed to the standard used in VPN services.
Media Authorization (RFC 3313)
Ensures that only authorized media resources are used.
Mobile Registration (RFCs 3327 and 3608)
On IMS networks, the terminal registration process is more complicated, as it includes various security extensions and must deal with registration from a visited network. RFC 3608 and RFC 3327 define the syntax and SIP entity usage of the Service-route and Path headers.
Reg-event Package (RFC 3680)
Used by the terminal and the P-CSCF to know the terminal registration status on the network.
IPv6
IMS prefers IPv6 networks, which offers distinct advantages. It permits a larger set of addresses and contains embedded IPSec functionality that may eliminate the need for entities like NATs and firewalls.
Preconditions (RFC 4032)
Specifies method for negotiating QoS, security and other required call behavior between two terminals.
IMS Resource Reservation (RFC 3312)
Defines how to make resource reservations for phone calls or sessions.
Session Description Protocol (SDP)
SDP defines the basic negotiation process for the media streams, and includes the bit rate and codec to be used, as well as other media attributes. IMS extends SDP with even more extensions, such as grouping of media lines, QoS and preconditions attributes, supplemental codec support, and bandwidth modifiers.
XML Usage
IMS SIP signaling uses XML protocols extensively, including XCAP, to implement various kinds of SIP message contents, and to allow full function interfaces between IMS entities.
IMS Simple Extensions
The SIMPLE group is an IETF working group that defines presence and instant messaging signaling requirements. Basic SIMPLE definitions were inadequate for IMS applications because they were not efficient enough for use on the air link. IMS SIP extended this standard with the following:
. Partial Notifications / Publications
. Notifications filtering
. Resource list / SIP exploders
. Message Session Relay Protocol (MSRP)
IMS SIP Expertise: A Prerequisite for Success
The use of SIP in IMS networks requires a great deal of adaptation and extension of the original signaling protocol. Given the breadth, variety and complexity of IMS SIP, it is indeed an arduous task to develop new services and applications from scratch. A more reasonable approach is to use prepared toolkits and infrastructure products that encompass all the nuances of IMS SIP, and where much of the development effort and interoperability testing (IOT) have already been completed.
In order to execute IMS roadmaps and ensure on-time deployment, developers need solutions that are finely tuned to the unique characteristics of IMS SIP and that provide the extended SIP signaling infrastructure needed for IMS applications.
Tuesday, November 16, 2010
Text Messaging Costs
Aside from calling, text messaging is the feature getting the greatest use on most cell phones and probably the primary reason for higher than expected bills. With the cost of sending a domestic message around $.15 and receiving one approximately $.10 with the typical cell phone plan, an avid user can rack up an exorbitant bill within days.
Customers have struggled to reign in the costs. Individuals and families have instituted "call, don't text" rules within their household, only to find that received text messages still send them over the edge. In some instances, users have been able to block texting from their service but then miss the privacy and the efficiency that texting offers. Many families have tried to quell an adolescent's texting excess by making teens responsible for their own texting costs while others provide only prepaid services to assure that usage is held in check.
However, an answer to the cost of the burgeoning use of text messaging which may create greater family harmony while allowing consumers to make full use of the feature may come from the cellular providers. Increasingly, the major players in the telecommunications industry are providing cell phone plans which offer options that will cap texting expenses. Cell phone plans which include unlimited texting features are increasingly common while adding on a more predictable $10 to $20 per month to the plan cost.
All "unlimited texting" cell phone plans however are not necessarily equal and consumers will need to shop to find the plan that fits their usage. The following items are some of the major things to consider when comparing plans:
• How much texting is used?
If a consumer only sends/receives a few hundred messages per month, the cellular provider probably offers a texting feature with a cap at 200, 300, or 500 messages which will be less expensive than a cell phone plan that offers no limit on texting.
• Does the unlimited plan include out of network messaging?
Many now do but some can be limited to messages only within the same network.
• Does the unlimited plan include just texting?
Some of the newer unlimited texting cell phone plans include not only texting but also picture and video messaging which is an important distinction for those who use such features routinely.
• Is there a data transfer cap?
Some "unlimited" plans actually cap the amount of data transferred and will charge additional for amounts that exceed the cap.
• Will unlimited texting apply to all lines?
For those who have multiple lines within their cell phone plan, it is important to know if all lines are covered.
• Is international text messaging included in the unlimited messaging?
In many cases it will not be, and the average $.35 cost per sent message can be a rude surprise if consumers are caught unaware.
• Can you discontinue unlimited text messaging at any time?
In some cases, the unlimited messaging is an add-on feature and it can be dropped to reduce the expense at any time. In other instances, the unlimited messaging is part of the cell phone plan itself. Some carriers allow consumers to switch plans at will, while others to do not. Consumers just need to know what flexibility they will or will not have during the contract period.
Customers have struggled to reign in the costs. Individuals and families have instituted "call, don't text" rules within their household, only to find that received text messages still send them over the edge. In some instances, users have been able to block texting from their service but then miss the privacy and the efficiency that texting offers. Many families have tried to quell an adolescent's texting excess by making teens responsible for their own texting costs while others provide only prepaid services to assure that usage is held in check.
However, an answer to the cost of the burgeoning use of text messaging which may create greater family harmony while allowing consumers to make full use of the feature may come from the cellular providers. Increasingly, the major players in the telecommunications industry are providing cell phone plans which offer options that will cap texting expenses. Cell phone plans which include unlimited texting features are increasingly common while adding on a more predictable $10 to $20 per month to the plan cost.
All "unlimited texting" cell phone plans however are not necessarily equal and consumers will need to shop to find the plan that fits their usage. The following items are some of the major things to consider when comparing plans:
• How much texting is used?
If a consumer only sends/receives a few hundred messages per month, the cellular provider probably offers a texting feature with a cap at 200, 300, or 500 messages which will be less expensive than a cell phone plan that offers no limit on texting.
• Does the unlimited plan include out of network messaging?
Many now do but some can be limited to messages only within the same network.
• Does the unlimited plan include just texting?
Some of the newer unlimited texting cell phone plans include not only texting but also picture and video messaging which is an important distinction for those who use such features routinely.
• Is there a data transfer cap?
Some "unlimited" plans actually cap the amount of data transferred and will charge additional for amounts that exceed the cap.
• Will unlimited texting apply to all lines?
For those who have multiple lines within their cell phone plan, it is important to know if all lines are covered.
• Is international text messaging included in the unlimited messaging?
In many cases it will not be, and the average $.35 cost per sent message can be a rude surprise if consumers are caught unaware.
• Can you discontinue unlimited text messaging at any time?
In some cases, the unlimited messaging is an add-on feature and it can be dropped to reduce the expense at any time. In other instances, the unlimited messaging is part of the cell phone plan itself. Some carriers allow consumers to switch plans at will, while others to do not. Consumers just need to know what flexibility they will or will not have during the contract period.
Cell Phone Insurance
Our cell phones are a life line, a work tool, and in some cases, the tie that binds families. To be without a cell phone is unimaginable for many but it is a reality that they are faced with at some time as record numbers of handsets are lost, stolen, or rendered useless each year. However, in a nation that attempts to insure every possession, cell phone insurance is available.
Numerous insurers have popped up in recent years promising to end the turmoil caused by the unexpected absence of these handy devices. These companies reassure us that we won't go more than a matter of hours when a cell phone is stolen as they strive to quickly resolve claims and replace our valuable goods. But is this insurance really cost effective? Does it provide the service that consumers anticipate? Potential buyers need to take the time to seek out the details of a policy before deciding that such insurance is a solution to the issue of a cell phone gone missing or bad.
When reviewing a cell phone insurance policy, buyers should consider a few things:
Consider the cost of the coverage.
This includes the monthly payments times the number of months the owner anticipates having the phone. For instance, a $5/month policy held on a phone that is owned for 3 years would total $180. That is $5 x 36 months = $180. Now the potential buyer must also factor in any deductible. For our example lets say there is a $50 deductible. The new total of $230 represents what the buyer would actually be paying if indeed their phone had to be replaced. Consumers need to compare the cost of a new, equivalent cell phone compared to the cost of the coverage. If they can obtain a new phone on their own for nearly the same amount as the cost of the policy, they are better off forgoing the insurance.
How are cell phones replaced?
Is there a guarantee that the phone will be replaced with a model of equivalent or better value? A guarantee that the phone will be new rather than refurbished? Is there language assuring the time frame in which the phone will be replaced? These types of questions will help determine whether or not the service will meet the needs for immediacy in obtaining a replacement and if the replacement will be inferior or equivalent to the original equipment.
What does the cell phone insurance policy cover?
Does the policy apply to cell phone theft, cell phone loss, and significant damage? It is important to know which situations are covered and which are most likely to occur. If the policy does not cover the situations that a particular buyer is most concerned with, then the policy is useless to them. Many policies will differentiate between loss and theft; sometimes requiring a police report for thefts.
Know what the cellular provider can do in these instances
Some cellular providers are willing to help replace a damaged or missing cell phone that a user has had for more than a year. In some cases, a replacement will be provided or discounted, minimizing the need for the additional protection of cell phone insurance.
Like any type of insurance coverage, cell phone insurance could provide significant assistance in quickly replacing a vital device that an owner can not afford to replace in some circumstances. However, in many instances it is merely an added expense. Consumers need to carefully review the policy to determine whether or not it offers the type of protection they need for their cell phone.
Numerous insurers have popped up in recent years promising to end the turmoil caused by the unexpected absence of these handy devices. These companies reassure us that we won't go more than a matter of hours when a cell phone is stolen as they strive to quickly resolve claims and replace our valuable goods. But is this insurance really cost effective? Does it provide the service that consumers anticipate? Potential buyers need to take the time to seek out the details of a policy before deciding that such insurance is a solution to the issue of a cell phone gone missing or bad.
When reviewing a cell phone insurance policy, buyers should consider a few things:
Consider the cost of the coverage.
This includes the monthly payments times the number of months the owner anticipates having the phone. For instance, a $5/month policy held on a phone that is owned for 3 years would total $180. That is $5 x 36 months = $180. Now the potential buyer must also factor in any deductible. For our example lets say there is a $50 deductible. The new total of $230 represents what the buyer would actually be paying if indeed their phone had to be replaced. Consumers need to compare the cost of a new, equivalent cell phone compared to the cost of the coverage. If they can obtain a new phone on their own for nearly the same amount as the cost of the policy, they are better off forgoing the insurance.
How are cell phones replaced?
Is there a guarantee that the phone will be replaced with a model of equivalent or better value? A guarantee that the phone will be new rather than refurbished? Is there language assuring the time frame in which the phone will be replaced? These types of questions will help determine whether or not the service will meet the needs for immediacy in obtaining a replacement and if the replacement will be inferior or equivalent to the original equipment.
What does the cell phone insurance policy cover?
Does the policy apply to cell phone theft, cell phone loss, and significant damage? It is important to know which situations are covered and which are most likely to occur. If the policy does not cover the situations that a particular buyer is most concerned with, then the policy is useless to them. Many policies will differentiate between loss and theft; sometimes requiring a police report for thefts.
Know what the cellular provider can do in these instances
Some cellular providers are willing to help replace a damaged or missing cell phone that a user has had for more than a year. In some cases, a replacement will be provided or discounted, minimizing the need for the additional protection of cell phone insurance.
Like any type of insurance coverage, cell phone insurance could provide significant assistance in quickly replacing a vital device that an owner can not afford to replace in some circumstances. However, in many instances it is merely an added expense. Consumers need to carefully review the policy to determine whether or not it offers the type of protection they need for their cell phone.
Data Service Plans
The history of the cell phone has seen an evolution from simple communication devices to the smartphones that are prevalent today. With these more advanced cousins of the original cell phone, internet capabilities such as text messaging and web browsing, audio and video playback, and the ability to sync up with a PC have been added to their work load. For busy consumers who want to increase their connectivity and productivity, a smartphone is an excellent option to provide the access and tools that are needed.
Once the decision is made to move up to a smartphone however, purchasing a web enabled cell phone is only the first step in the process of getting started. Cell phones operate in conjunction with a voice plan from a cellular provider; when using such a device for internet related functions, the user must have a data plan to make the appropriate connection.
When considering a data plan for a cell phone there are a number of details to consider:
What functions will be used?
Users need to carefully consider what functions they will be needing. Some data plans allow e-mail functions only, providing the benefit of a lower monthly cost. Other plans allow users to send and receive e-mail via their cell phone, access the internet, download games, music, video, sync with their PC to access various software applications, and perform a variety of other functions.
Users also want to be sure they know what web access they will be allowed via their data plan. Some plans allow access to selected sites only while others provide unlimited access. Some data plans allow internet access via cell phone but not on a laptop when tethered to a cell phone acting as a modem. The data plan will need to match up with how the individual wishes to use the service.
Is the coverage sufficient?
Just as with a voice plan, users should check to assure that the coverage through the data plan will be sufficient for their location and in other locations where they will commonly need to access the service through their cell phone. In some instances, the quality or speed of the connection can vary from location to location.
What is the cost of the data service plan?
Cell phone owners are charged a monthly fee for their data plan. Users pay for data plans through either the amount of data used or the time spent on the service. Data use fees may be based on a predetermined amount of data transmitted and received over the course of a month or may be "unlimited".
Plans which charge a set fee for a prescribed amount of data transfer may be economical if use of the service is very limited and consists primarily of e-mails and text documents. However, in many instances, unlimited plans that set no limit on the number of megabytes used in a month are often a safer option. As an example, a plan with limited data transfer may allow 5MB per month but receiving a single MP3 music file could consume 3-4MB alone. Just as with voice plans, it is expensive to exceed the data plan limits; average $.06 per kilobyte.
As mentioned above, rather than charging for the amount of data transfer, some cellular providers draw from voice plan minutes to cover time spent on the web. Individual users would need to carefully assess whether or not the consumption of additional voice time would be the best option for them.
As cell phones have matured into the smartphones of today, millions of busy, time limited people are finding them increasingly indispensable. However, new users will need to learn the details of the various data plans to assure that their new web enabled cell phone can meet their expectations.
Once the decision is made to move up to a smartphone however, purchasing a web enabled cell phone is only the first step in the process of getting started. Cell phones operate in conjunction with a voice plan from a cellular provider; when using such a device for internet related functions, the user must have a data plan to make the appropriate connection.
When considering a data plan for a cell phone there are a number of details to consider:
What functions will be used?
Users need to carefully consider what functions they will be needing. Some data plans allow e-mail functions only, providing the benefit of a lower monthly cost. Other plans allow users to send and receive e-mail via their cell phone, access the internet, download games, music, video, sync with their PC to access various software applications, and perform a variety of other functions.
Users also want to be sure they know what web access they will be allowed via their data plan. Some plans allow access to selected sites only while others provide unlimited access. Some data plans allow internet access via cell phone but not on a laptop when tethered to a cell phone acting as a modem. The data plan will need to match up with how the individual wishes to use the service.
Is the coverage sufficient?
Just as with a voice plan, users should check to assure that the coverage through the data plan will be sufficient for their location and in other locations where they will commonly need to access the service through their cell phone. In some instances, the quality or speed of the connection can vary from location to location.
What is the cost of the data service plan?
Cell phone owners are charged a monthly fee for their data plan. Users pay for data plans through either the amount of data used or the time spent on the service. Data use fees may be based on a predetermined amount of data transmitted and received over the course of a month or may be "unlimited".
Plans which charge a set fee for a prescribed amount of data transfer may be economical if use of the service is very limited and consists primarily of e-mails and text documents. However, in many instances, unlimited plans that set no limit on the number of megabytes used in a month are often a safer option. As an example, a plan with limited data transfer may allow 5MB per month but receiving a single MP3 music file could consume 3-4MB alone. Just as with voice plans, it is expensive to exceed the data plan limits; average $.06 per kilobyte.
As mentioned above, rather than charging for the amount of data transfer, some cellular providers draw from voice plan minutes to cover time spent on the web. Individual users would need to carefully assess whether or not the consumption of additional voice time would be the best option for them.
As cell phones have matured into the smartphones of today, millions of busy, time limited people are finding them increasingly indispensable. However, new users will need to learn the details of the various data plans to assure that their new web enabled cell phone can meet their expectations.
Better Pictures
Camera capabilities have become common on cell phones and, for some users, these camera phones are their only means of capturing and sharing images. Certainly, the camera within a cell phone is readily available and portable, making them a good option for more spontaneous photography. In addition, they are less conspicuous than all but the more compact stand alone digital cameras, allowing users to take more candid shots easily.
Cell phone cameras also have a reputation for their limitations however. From slower shutter speeds that make blurry pictures likely, lack of manual control to adjust exposure, white balance, focus, and so forth, to the common lack of high quality lenses, CMOS sensors, and the megapixels necessary for sharp images, the average camera phone often doesn't compete well with stand alone digital cameras for producing high quality images for print.
With recent advancements in the design of cell phone cameras however, consumers can now find devices that are capable of creating far better images, even in the printed form. By choosing the right camera phone and employing a few basic photographic techniques, the images users create are usually quite acceptable.
For users who want to be able to print sharp, detailed 5x7 images, there are a few things to consider when making a camera phone purchase:
• Get better resolution. Until recently a 1.3 megapixel camera was the best available. Now cell phones that offer a camera with a CMOS sensor and 3 megapixels, or more, are available.
• Get a higher quality lens, and protect it. Some cell phone cameras offer better lenses; a Carl Zeiss lens for instance is highly regarded. Getting a lens cover to protect the lens from scratches, dirt, and dust can be important too; cell phones are often thrown into situations and locations that put them at risk for damage.
• Get features to reduce camera shake. Cell phones are small, thus more difficult to hold steady. Slower shutter speeds further exacerbate the need for a very steady hand. A camera with optical image stabilization can help to reduce blurriness and one that the user can securely grip is a bonus as well.
• Get optical zoom. Many cell phone cameras offer digital zoom. Better cameras offer optical zoom. When photographers can't step close to a subject, optical zoom is the answer without reducing image quality.
• Get features that allow some manual control. Great photographs often require photographers to adjust exposure, white balance, and focus. At a minimum, a user should have the option of turning off the flash.
• Get an LCD that helps in framing the scene that is to be photographed. A screen with a large viewing area is important in setting up shots. Good viewability should be checked, especially in sunlight. Potential buyers should pick the cell phone up and try framing a few shots indoors, and outdoors if possible.
Once a good camera phone is in hand, users then need to heed a few critical photographic rules that are particularly pertinent when shooting with small cell phone devices:
• Use high resolution settings on the camera phone in case prints are desired later; prints require higher resolution than sharing images on a screen.
• Keep the camera steady. Try holding the cell phone with both hands, bracing arms/elbows against the body. Try bracing against a doorway, a tree, a table, and so forth for added stability. It can also be useful to remain stationary for a few seconds after pressing the button to assure that the camera has completed the process of capturing the image.
• Get close to the subject. Camera phones are better at capturing nearby subjects rather than landscapes and such. Avoid using digital zoom.
• Keep the lens clean. Cell phones, as noted before, tend to be tossed around and accumulate a lot of fingerprints, dirt, and scratches without extra care.
• Lighting is critical as in all photography. Camera phones are better adapted for outdoor use in general. Avoid backlighting subjects; side lighting is generally best.
Cell phone cameras are improving and, although not yet competitive with most stand alone digital cameras, are capable of producing very acceptable images for the average user. For those who value the photographic ability of their cell phone, good options are available if they know how to make the right choice and are able to compensate for their limitations with good photographic techniques.
Cell phone cameras also have a reputation for their limitations however. From slower shutter speeds that make blurry pictures likely, lack of manual control to adjust exposure, white balance, focus, and so forth, to the common lack of high quality lenses, CMOS sensors, and the megapixels necessary for sharp images, the average camera phone often doesn't compete well with stand alone digital cameras for producing high quality images for print.
With recent advancements in the design of cell phone cameras however, consumers can now find devices that are capable of creating far better images, even in the printed form. By choosing the right camera phone and employing a few basic photographic techniques, the images users create are usually quite acceptable.
For users who want to be able to print sharp, detailed 5x7 images, there are a few things to consider when making a camera phone purchase:
• Get better resolution. Until recently a 1.3 megapixel camera was the best available. Now cell phones that offer a camera with a CMOS sensor and 3 megapixels, or more, are available.
• Get a higher quality lens, and protect it. Some cell phone cameras offer better lenses; a Carl Zeiss lens for instance is highly regarded. Getting a lens cover to protect the lens from scratches, dirt, and dust can be important too; cell phones are often thrown into situations and locations that put them at risk for damage.
• Get features to reduce camera shake. Cell phones are small, thus more difficult to hold steady. Slower shutter speeds further exacerbate the need for a very steady hand. A camera with optical image stabilization can help to reduce blurriness and one that the user can securely grip is a bonus as well.
• Get optical zoom. Many cell phone cameras offer digital zoom. Better cameras offer optical zoom. When photographers can't step close to a subject, optical zoom is the answer without reducing image quality.
• Get features that allow some manual control. Great photographs often require photographers to adjust exposure, white balance, and focus. At a minimum, a user should have the option of turning off the flash.
• Get an LCD that helps in framing the scene that is to be photographed. A screen with a large viewing area is important in setting up shots. Good viewability should be checked, especially in sunlight. Potential buyers should pick the cell phone up and try framing a few shots indoors, and outdoors if possible.
Once a good camera phone is in hand, users then need to heed a few critical photographic rules that are particularly pertinent when shooting with small cell phone devices:
• Use high resolution settings on the camera phone in case prints are desired later; prints require higher resolution than sharing images on a screen.
• Keep the camera steady. Try holding the cell phone with both hands, bracing arms/elbows against the body. Try bracing against a doorway, a tree, a table, and so forth for added stability. It can also be useful to remain stationary for a few seconds after pressing the button to assure that the camera has completed the process of capturing the image.
• Get close to the subject. Camera phones are better at capturing nearby subjects rather than landscapes and such. Avoid using digital zoom.
• Keep the lens clean. Cell phones, as noted before, tend to be tossed around and accumulate a lot of fingerprints, dirt, and scratches without extra care.
• Lighting is critical as in all photography. Camera phones are better adapted for outdoor use in general. Avoid backlighting subjects; side lighting is generally best.
Cell phone cameras are improving and, although not yet competitive with most stand alone digital cameras, are capable of producing very acceptable images for the average user. For those who value the photographic ability of their cell phone, good options are available if they know how to make the right choice and are able to compensate for their limitations with good photographic techniques.
Phone in Every Pocket
Cell phones (telefone celular) or mobile phones have had a great impact on the way we lead our lives. In today's world, where change is the only constant, cell phones have been upgraded with lots of new technological features. There has been a tremendous growth in the use of cell phones all over the world and now almost anybody has a personal cell phone. What started in 1960s as a bulky radio communication equipment to be used at the time of war, it has now become a small pocket device with a host of special features specially crafted for the common consumer. It satisfies more than the basic need to communicate. It is a fashion statement - an identity of self - and it comes in hundreds of models. Nokia is the world's largest manufacturer of cell phones followed by Motorola, Samsung, BenQ, Siemens, Panasonic, Philips, LG, NEC, Sony Ericsson, Fujitsu and many more. Apart from calling and texting, cell phones are used for a variety of purposes - to keep contact information, to make task lists and daily schedules, browse mobile websites and check emails, play games, watch video clips, listen to music, take pictures and much more. Also cell phones (telefone celular) are easy to integrate with other electronic devices such as notebooks, music systems and etc. With the availability of infrared and Bluetooth technology, a lot of wireless connectivity is possible, such as the use of wireless headphones. Also you can make your phone interact with your notebook without any physical connection.
So, what should you look for while purchasing a new cell phone (telefone celular)? The points to consider include the service plan, price, size, weight, features and technical specifications, compatibility with other devices, display screen resolution and a very important feature: battery life. The latest features offered by cell phones are mega pixel camera, wireless connectivity, modem capability, PC synchronization, music and video player and a lot more.
Today, you can access the World Wide Web through your cell phone (telefone celular). To access internet, your cell phone has to be WAP-enabled. Many companies have created mobile compatible websites that make browsing on your phone very easy. You can get the latest news, stock quotes and game scores on the move through your cell phone. The advanced third-generation phones (3G phones) will soon storm the market and will have high-end graphical display that will enable better video conferencing and gaming experience.
Everybody must follow basic cell phone (telefone celular) etiquettes. Your mobile should not ring in public and disturb others. Sometimes mobile phones ring at odd instances like in movie theatres, weddings, funerals, important official meetings, etc., and to top it the fancy ring tones disturb everybody else around you. You should keep your cell phone in the silent mode when you are at a public place and you must never talk on the cell phone while driving. This might put you in trouble in many countries as there are heavy fines on cell phone misuse.
Cell phones (telefone celular) have become an intrinsic part of our lives that most of us cannot imagine a single day without it. Ring tones, caller tunes, mobile gaming, camera, texting, MMS and video messaging, audio and video recording and viewing are still not enough. New technologies are developed often to reduce size and weight, increase speed, provide a better user interface, to pack more high-definition features into a small pocket device. With GPS (global positioning system) capability, cell phones have become so useful that a person carrying one could be located to a range of a few meters, anywhere on the globe! GPS cell phones are important devices in locating users in emergency situations, which allows emergency services to be quickly dispatched.
So, what should you look for while purchasing a new cell phone (telefone celular)? The points to consider include the service plan, price, size, weight, features and technical specifications, compatibility with other devices, display screen resolution and a very important feature: battery life. The latest features offered by cell phones are mega pixel camera, wireless connectivity, modem capability, PC synchronization, music and video player and a lot more.
Today, you can access the World Wide Web through your cell phone (telefone celular). To access internet, your cell phone has to be WAP-enabled. Many companies have created mobile compatible websites that make browsing on your phone very easy. You can get the latest news, stock quotes and game scores on the move through your cell phone. The advanced third-generation phones (3G phones) will soon storm the market and will have high-end graphical display that will enable better video conferencing and gaming experience.
Everybody must follow basic cell phone (telefone celular) etiquettes. Your mobile should not ring in public and disturb others. Sometimes mobile phones ring at odd instances like in movie theatres, weddings, funerals, important official meetings, etc., and to top it the fancy ring tones disturb everybody else around you. You should keep your cell phone in the silent mode when you are at a public place and you must never talk on the cell phone while driving. This might put you in trouble in many countries as there are heavy fines on cell phone misuse.
Cell phones (telefone celular) have become an intrinsic part of our lives that most of us cannot imagine a single day without it. Ring tones, caller tunes, mobile gaming, camera, texting, MMS and video messaging, audio and video recording and viewing are still not enough. New technologies are developed often to reduce size and weight, increase speed, provide a better user interface, to pack more high-definition features into a small pocket device. With GPS (global positioning system) capability, cell phones have become so useful that a person carrying one could be located to a range of a few meters, anywhere on the globe! GPS cell phones are important devices in locating users in emergency situations, which allows emergency services to be quickly dispatched.
GPS Cell Phone
The Global Positioning System (GPS) was funded, developed and controlled by the US Department of Defense. Since the late seventies, GPS has become an important aid to navigation around the world. Initially designed for the US military, GPS became publicly available years later and it is now considered an important feature in lots of consumer products.
How does GPS work? Well, basically there are three elements that make everything work: satellites, earth monitoring stations and receivers (ex: cell phone, telefone celular). GPS provides specially coded satellite signals that can be processed in a GPS receiver, enabling the receiver to compute position, velocity and time.
Today, most cell phones (telefone celular) are not limited to carry on just a conversation. Features like mp3 player, digital camera and video camera have all become standards in the latest cell phone models. It is expected that the GPS feature will soon be added to this list, and it will offer the capability of tracking any cell phone user.
The capability of tracking a cell phone user becomes important in emergency situations, like a car accident, thru the use of 911 emergency phone call, where every minute may be a matter of life or death. In situation like this, the GPS system may pinpoint the exact location of the road accident, enabling emergency services to be quickly dispatched.
It is important to mention that so far most GPS system in cell phone (telefone celular) is restricted to tracking information only. However, one can have navigational capability thru the use of full screen cell phone/PDA combos with map displays and other cellular phone accessories, and third party paid services. If one does not want to sign up for a monthly paid subscription service, he can make use of one-time-paid-only software programs that will enable some of the navigational capabilities.
Although there are many benefits in using GPS cell phones (telefone celular), there are some people who are concerned about the violation of personal privacy. Since the US Congress has not authorized location tracking without actual evidence of wrongdoing, there have been court hearings which have not approved the requests of government agencies in obtaining the cell phone GPS tracking information for suspects or ordinary citizens.
This privacy matter has made some progress towards the cell phone user`s rights, since there are some laws that have been passed which guarantees that GPS cell phone users will have some protection from the release of the tracking information, with the exception of 911 emergency cell phone calls (telefone celular). It is expected that these laws will guarantee that the benefits of GPS in cell phones will be enjoyed by everyone without infringing anybody`s privacy.
Sometimes when there is a technological innovation, there are also some concerns about privacy or some rights infringements. But no matter how much of a concern this is, it seems that a compromise will always have to be reached, so that new technologies will take their places in everyone`s lives. After all, we all live in a globalized consumer world. By the way, have you already got your GPS cell phone?
How does GPS work? Well, basically there are three elements that make everything work: satellites, earth monitoring stations and receivers (ex: cell phone, telefone celular). GPS provides specially coded satellite signals that can be processed in a GPS receiver, enabling the receiver to compute position, velocity and time.
Today, most cell phones (telefone celular) are not limited to carry on just a conversation. Features like mp3 player, digital camera and video camera have all become standards in the latest cell phone models. It is expected that the GPS feature will soon be added to this list, and it will offer the capability of tracking any cell phone user.
The capability of tracking a cell phone user becomes important in emergency situations, like a car accident, thru the use of 911 emergency phone call, where every minute may be a matter of life or death. In situation like this, the GPS system may pinpoint the exact location of the road accident, enabling emergency services to be quickly dispatched.
It is important to mention that so far most GPS system in cell phone (telefone celular) is restricted to tracking information only. However, one can have navigational capability thru the use of full screen cell phone/PDA combos with map displays and other cellular phone accessories, and third party paid services. If one does not want to sign up for a monthly paid subscription service, he can make use of one-time-paid-only software programs that will enable some of the navigational capabilities.
Although there are many benefits in using GPS cell phones (telefone celular), there are some people who are concerned about the violation of personal privacy. Since the US Congress has not authorized location tracking without actual evidence of wrongdoing, there have been court hearings which have not approved the requests of government agencies in obtaining the cell phone GPS tracking information for suspects or ordinary citizens.
This privacy matter has made some progress towards the cell phone user`s rights, since there are some laws that have been passed which guarantees that GPS cell phone users will have some protection from the release of the tracking information, with the exception of 911 emergency cell phone calls (telefone celular). It is expected that these laws will guarantee that the benefits of GPS in cell phones will be enjoyed by everyone without infringing anybody`s privacy.
Sometimes when there is a technological innovation, there are also some concerns about privacy or some rights infringements. But no matter how much of a concern this is, it seems that a compromise will always have to be reached, so that new technologies will take their places in everyone`s lives. After all, we all live in a globalized consumer world. By the way, have you already got your GPS cell phone?
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