PCinfospace

You hear so much about protocols.  To the average person this may seem like French or at least a language you don’t understand.

I will attempt to simplify it here.  It is a language or process that uses certain rules. It is the kind of language needed to communicate between one device and another, one computer or another or even one network and another. It is the process need to accomplish a specific task. EXAMPLE: The phone rings, you pick up the receiver (with a cell phone you maybe just flip open the cover). You normally say hello and the conversation begins. If the person doesn’t answer you know there is a problem and you use a certain process to solve it.

In networks very stringent rules must be followed for things to work. A network card must know how to talk to other network cards in order to pass on information. Operating system must know how to talk to networks cards etc.

Some examples of protocols are TCP/IP,FTP,IPX/SPX along with many others.

If you plan to work with networks at all you must understand what a protocol is and which ones work together. For example: if you want to send large amounts of data to or from a server you may want to know what FTP is. This stands for File Transfer Protocol and is widely used to move files to and from servers and of other data transfer points.

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This is a very common problem.  This can also relate to trying to open a document that is sent to you over you office network or through a USB drive or CD or other media.

Here is an example: If you receive an e-mail with an attachment that you can’t open it is probably because you have an earlier version of the software program.  If you have Word 97 and the person that sent the document has Word 2007 you will not be able to open it.  Also, if you do not have the program at all you will not be able to open what somebody sent you.

What about PDF files?
There are quite a few PDF file being sent these days.  In fact a high percentage of all Company attachments are PDF format.  If you don’t have Adobe Reader or a version that is up to date you may not be able to read the PDF form sent to you.

In the past most people were not upgrading their computers or at least not their production packages such as Office.  With the introduction of Window XP many of the old programs were not compatible and people were forced to change.  When Vista came around this became more urgent than ever.  In XP most of the old programs would work in compatibility mode.  Not so in Vista.  Now Windows 7 is here. Prior programs may not work in this operating system either. This quickly weeded out old printers because manufactures did not make drivers that were compatible to older systems.  A wider range of people were buying laptop also.  These all came with the latest and greatest operating system only adding to the already complex problem.

Driver updates
The biggest problem when you change operating system is drivers for video cards, sound or even your network card may need to be updated and/or even totally changed.

Hardware issues
Periodically you may need to change your hardware because the manufacturer doesn’t make a driver or software compatible to the newer operating system.

How to fix this
You can ask the person that sent the document to send you a copy that is farther back or equal to the one you have. Most programs such as Word allow you to save it in an earlier version. This is a fix if you just don’t want to upgrade.  However, the number of times you have to do this may become unbearable.

Try to keep your computer up to date the best you can.  You will most likely be forced to buy the latest and greatest word processing program or other programs that will work with your system. Mostly it should be worth the upgrade.  The newer computers are much faster and have features that may help you in doing things better and maybe faster.

I should define the word packet before I start.  A packet is a message that is sent over the network from one node (Computer) to another node. The packet includes the address of the node that sent the packet, the address of the node the packet is being sent to, and the data.

I feel that a person that uses networks or wants to understand how they work should at least read about this concept.

It is a “model” because it is a general theory.  Defined: O.S.I.  stands for Open System Interconnection Reference Model.  It is a description of layered communications and computer network protocol design.  A protocol is a language needed to communicate between one device or piece of hardware and another. It is normally integrated into the operating system of the computer.

The model divides the Network into seven layers. These layers are: Application, Presentation, Session, Transport, Network, Data-Link, and Physical Layers. Each layer provides service to the layer above it.

The seven layers are:
1. Physical – Controls the layout of cables and devices such as repeaters, hubs and Network Interface Cards.
2. Data Link – Provides  MAC (Media Access Control) addresses  to uniquely identify network nodes and a means for data to be sent over the physical layer in the form of packets. Bridges and switches are layer 2 devices.
3. Network – Handles routing network messages from one computer to another.
4. Transport – Concerns the transfer of information from one computer to another. The purpose is to have packets  transported reliably and without error. This is where you find the TCP (Transmission Control Protocol).
5. Session – Establishes sessions between network applications. Session layers include:  Simplex,
Half-duplex and Full-duplex.
6. Presentation – Converts data so that systems that uses different data formats can exchange information. In other words, the presentation layer transforms data so that the application layer can understand it.
7. Application – Allows applications to request network services. This layer represents the programming interfaces programs such as Microsoft Office or QuickBooks  to request network services. Some Application Layer protocols include: DNS, FTP,SMTP ,SMB, NFS and Telnet.

The above information may or may not be easy to understand.  It is however, a general definition of what every bit and packet of information goes through.  It could serve as a means of troubleshooting.  If you understand which layer is causing the problem you may be able to zero in on why the network isn’t working.

Bluetooth is a short-range wireless technology designed to connect devices to each other without the use of a cables or a wireless access point.  It is one way to create a network of computers.
Uses of this technology include but are not limited to:
§    Keyboards
§    Mice
§    Phones
§    PDAs
§    Cord free headsets
§    Global Positioning Systems

The list above keeps growing and the devices keep getting better and cheaper.

Here is some general information that may interest you.

§    This technology was turned into a standard known as 802.15 in 1998 by a consortium of companies.
§    Bluetooth operates at 2.4GHz.  This is the same frequency as some cell phones and WI-FI networks.  This has caused some interference problems.  This is the reason wireless phone started to be manufactured that were over 5GHz.
§    Bluetooth operates at 721Kbps which is slower than WI-FI. It is not designed to carry large amounts of data.  WI-FI is used for that purpose.
§    Because Bluetooth operates at low power it is ideal for cell phones, PDAs and other devices.
§    Bluetooth come in three classes.  Class I is one hundred Megawatts and its range is 300 feet, Class II is ten Megawatts, and has a range of 30 feet and Class III which is only one Megawatt and has a range of less than 30 feet.

How do you add Bluetooth to your computer?

Many computers (especially laptops) now come with this technology.  If not, you only need to purchase a USB Bluetooth adapter.  If your computer has Windows XP with Service Pack 2 operating system or above it should install automatically. If it doesn’t install by itself a driver disk may be included or you may be sent to a web site to download a drive.  It will attempt to connect to any Bluetooth device within range.  Prices vary and change rapidly.