Net +

PDN, Public Data Networks!

2008-02-24T19:06:00.000-08:00

If you want to connect to someone from one of the States in America to another person in another country you can actually do that in two different ways. You can buy a PDN, a Public Data network. What a Public Data Network is , The providers takes care of the carrier, the routing services across the WAN, and the protocols. You deliver the data and the provider makes sure that the data gets to its destination.
What that actually means is that you send something over the network, and the provider just makes sure that it gets to the right place! The second option is to connect two distant offices to a contract carrier service. When you get involved with a contract carrier service they provide the hardware, but you have to deal with everything else, especially the routing issues!
Today we are going to talk about the grand daddy, big bad booty daddy. The server!
A server is a computer that provides shared resources to network users. A server is pretty much the computer that holds all of the data, that can be accessed by other computers that are connected to it. Now you can’t talk about a server unless you talk about the client. A client is a computer that access resources via the network on servers.

Here is a little example, a little tid bit that you can do, How to Share a folder.
This teaches you how to share a older on a Windows 95 workstation with share-level access control.
1. Open windows explorer by right-clicking on My Computer and selecting Explorer
2. Browse to the folder you want to share and right-click that folder.
3. Choose the option Sharing.
4. Select Shared as and enter a share name. Select the security level by clicking either Read-only, Full, or depends on Password.
5. Set a password for the chosen security level and click OK. If you do not set a password, anybody can access the folder with the given privilege.

Switched Networks, HUBS!

2008-02-22T23:32:00.000-08:00

Today we are going to discuss some Switched Networks. They have become quite popular lately. HUBS are devices that connects networked devices to each other. The problem with Hubs is that once one of them opens up to communicate with another, it opens up the port. Making it unusable for other Hubs in the network. A switching Hub can help remedy this problem. See it turns on a switch so it can connect the two hubs directly, and the other HUBS don’t have to deal with their communications and can communicate with other HUBS.
Now we’ve already discussed about LAN’s today let’s move on to WANs.
Now try to remember what we talked about with LAN’s. You see your company is now growing, all of your computers in your building are connected under a LAN. Now say that your company has expanded to all parts of the world. Your company needs to contact all of these other branches now, and try to communicate with one another. What to do? What to do? Well you can always set up a WAN. Which stands for Wide Area Network. It’s the same thing as a LAN but it has a larger geographical area! There are many great advantages to WAN’s. It’s easier to communicate, share, and organize data with other branches all across the states!

Net + Lessons, Repeaters, Bridges, and Broadcast storms!

2008-02-19T19:22:00.000-08:00

Well last time we discussed about Repeaters and Bridges, which were very simple concepts, but today we are going to into the disadvantages of the Bridges!
You see computers send out data packets without specific destination addresses, intended for all the computers it can reach. This is called a broadcast. A major disadvantage of bridge is that they don’t stop the broadcasts! Just think about a spam mailer, he lost his address book, so he just starts sending e-mails to EVERYONE on the internet! Since the broadcast packet doesn’t have a destination, the bridge has no other choice but to send it to everyone’s computer that is connected to the bridge. This can cause a BROADCAST STORM!!! Yeah it sounds scary, but that’s when the bridge sends the broadcasts to every segment on the network. It occurs when there are so many broadcast packets on the network that the capacity of the network bandwidth approaches or reaches saturation. The worst case scenario it can shut down the network!
Now that’s the professional definition of it, but try to take it apart and make it something simpler. Let’s say that you are making a smoothie, and you fill it up with loads of fruits and veggies. But then you start to overflow it, and now the blender won’t even start. You can use any other analogies that you want, as long as you understand the concept. TOO MUCH OF ANYTHING WILL SHUT IT DOWN!
The last thing that we will talk about today is the Routed Networks. See Routers are like the next step after the bridges. Bridges uses the destination MAC address, the Router uses the destination network address to see where a packet should go. Let’s pretend that the number of your house is your MAC, and the Network address is you street name. You can now see why using bridges can cause a broadcast storm right? You’d be sending all that information to anyone with the same numerical address as you. But with Routers it sends it to the STREET Address! Much more simpler.

Net + Lesson 2... Repeaters, and Bridges

2008-02-18T14:36:00.000-08:00

Ok welcome back, last time we talked about LAN, but we never discussed any of the medians that are used to carry certain signals from computer to computer. Now if you think about it, when you send something through any network, does the signal stay strong forever. Think about it this way, when you drive your car down the east coast, say from New York, all the way down to Florida, is that car going to get you there on one tank of gas? Well I know we’ve had some breakthroughs with some hybrid cars, but the answer is no. You’d have to stop at a gas station and fill your car up with gas to make it more powerful, more energized wouldn’t you?
Same thing goes for signals, you see when networks first started out they were very small, it’s understandable because that’s how everything starts out, small. See early network cables had short maximum lengths, so a lot of the signals would become weakened. What could they do in order to re-energize the signal? Well Using a Repeater of course.
Repeater connects network cables by regenerating signals so they can travel on additional cable lengths. I think you understand this concept from the whole car driving example above! Computers on either side of the Repeater could access data on their computers as long as they were using the same media access design and the same protocol and transmission method. It means that if you were in your office, you could log into one computer, open up your desktop and see all of your files. Then you can log off, go to the next computer and log in the same way, and all of your files will be there!
But there is a disadvantage of the Repeaters. They simply pass on any data they receive to both segments that are attached to the device. What this means, is, Say you have 10 computers, and 10 workers. One person wants to send a file to just one other person, but the Repeater sends that file to everyone’s computer. Now imagine if each person on the network wanted to send one file to one other person, that would mean that over a thousand files would be sent over to everyone computer and it could easily flood the network! But there is a solution, and that will be the last thing that we talk about for the day. That solution to this problem is called a BRIDGE! The BRIDGE is just like the Repeater, but it can filter the data that it receives. A great invention, in order to stop the overflow of data going into the network! Study hard, and try to take what you don’t understand, and make it simple!

The Reboot of Net + Lessons. LESSON 1!

2008-02-18T11:24:00.000-08:00

Ok, it’s been a while since I’ve been on here, but I’ve been busy learning, and memorizing a lot of information! So let’s restart everything, and since a lot of my old readers have left, we will try to get some new ones, we are going to start from the very very beginning!
All right, this is in no way shape or form a way of selling books online, this is just a guy, who is learning some computer stuff, and just helping out his fellow computer lovers out there! I heard that when you learn something you only retain so little of what you hear, but when you teach it to someone else, you’d retain about 50% of what your teaching or even more!

So let’s begin with the very first lesson!

What is a network? Hopefully everyone reading this should at least know what it means, even in the common sense, non computeristic way! Networking in the real world is to open one’s social circle and invite others into it, to discuss and communicate with one another! Networking that deals with computers is pretty much the same thing! A Network is two or more computers and their associated peripherals connected by a communication medium! Here is the jist of it.

Take two computers, and place them next to one another, are they going to share any information with each other? No they can’t talk, so what you have to do is use something to connect them to one another! See simple enough! All you need is something it connect them to one another!
Now we can start talking about LAN and WAN. LAN = Local Area Network, WAN = Wide Area Network.
I’m pretty sure that you can distinguish just exactly that means! If not then let’s discuss about LAN and WAN’s in some detail, but first we’ll go over the Local Area Network this time, and save WAN’s for later!
A LAN is a collection of computers that are connected in a geographically close network. What this means, is take for an example an office building. All of the computers are connected to one another. People can send their information from computer to computer, print from the same printer, do other things because they are all connected to one another in a small close area!
Study hard, and try to take what you don’t understand, and make it simple!

Net + Lesson 6

2007-09-24T21:53:00.000-07:00

Well today I'm going to go back and discuss about Bus topologies, because it seems like a tough subject! Well not really. its a very easy and interesting concept to grasp in NET +. Just imagine a row of buses, it's as simple as that.

Today we are going to talk about Repeaters.
Have you ever had a signal go weak on you? Well I haven't really, had a signal go weak on me, but I bet it happens to people all the time!
Repeters Work on the physical layer of the OSI model! Repeaters pretty much make signals stronger! Simple, and easy to understand

Bridges and Routers

They provide a way of segmenting network traffic and connect different LAN types.

Now If you plan ahead, you can efficiently use Routers and create a great system in which you can have an incredible communications environment!

Net + Lesson 5

2007-09-20T13:41:00.001-07:00

What is... and Operations Manager? Do you know? Well? Come on out with it... Let me know what an Operations Manager is! Well I guess i can give a small explanation for the whole thing about Operation managers!

It's pretty much like a secret agent that you put into your computer, so it can monitor the computer!
It watches a lot of things on the computer, such as Windows Event log for alerts etc!
There are a few Versions of Operations Managers
- Microsoft Operations Manager 2000
- Microsoft Operations Manager 2005
- System Center Operations Manager 2007

Well I know it's a random topic about operations managers, but My teacher talked about it today, and this is actually the notes he gave me... so I'm posting it!

Today we are going to talk about the differences between Baseband vs. Broadband!
- The baseband transmision method uses the media so that the cable is taken up by a single transmission

- Broadband communications, the communicators use different frequencies to seperate their messages from others by using the same media at the same time!
More tomorrow... we'll talk about Half-duplex... full-duplex!

Net + Lesson 4

2007-09-11T17:57:00.001-07:00

In today's lesson we will cover more things that have to do with.... NET + hahaha!
Today we are going to talk about the OSI model. Open Systems Interconnection Basic Reference Model
The OSI model has several layers... infact it has 7 whole layers. that's a lot of layers. The Seven Layers are as follows

7. Application
6. Presentation
5.Session
4.Transport
3. Network
2. Data link
1. Physical

Yeah it's back wards... in fact it goes from the bottom up.. kind of weird huh?

Today we are going to cover just two of the OSI model layers! First we'll discuss the Physical layer and the data link layer!

1. Physical layer-
This pretty much controls how data is transmitted across the media.

2. The OSI Data link layer-
The data link layer tells how devices attached to a network gain access to the various computing resources

There are two sub layers in the Data link layer:
-The logical Link control (LLC)
-Media Access Control (MAC)

Net + lesson 3

2007-09-10T19:05:00.000-07:00

Today, we are going to discuss in Net + about topologies. Some say that topologies are the hardest concepts to capture in Net +... But i think it's the easiest thing to learn out of all there is to learn in Net +.
There are four main types of topologies:
-Bus
-Ring
-Star
-Mesh
They are all pretty much self explanatory. But we have to go into a simplistic way of looking at all of these Topologies in Net +. I'll explain it the same way as I've understood it.

Bus topology:
Imagine a school bus... go ahead... did you imagine a bus yet? What a bus topology is... just that... a row of computers in a line all connected to one another. there is computer A connected to B... B is connected to C... etc... and they are all linked! So if one crashes... they all crash!

A Ring topology:
Just like a bus... imagine a circle... with computers all surrounding the entire ring. But this one has a File Server and Mau... in order for them to work... none of the computers can be broken!

Star Topology:
It seems to be the best... because the way it is set up... that if one computer is broken or working improperly... all the other computers won't be affected... So There is a central hub... which has it's own connections to each different computer... which makes networking easy!

Mesh topology:
Think of Mesh topology as a messy topology... it's like a group of three freinds... that live in different parts of the state... and they all stay connected to one another... like this...

ABCD
EFGH

A connects to E... F... G.... H
B connects to E...F...G...H...
ETC!!!

More next time folks... more on Net + and Networking!

Net + Lesson 2

2007-09-10T12:55:00.000-07:00

Today we will discus the Role of Network Operating Systems, servers, workstations, and hosts!

What is a network operating system you ask? Well In computer lingo it's NOS. It runs on a server in a cleint/server network configuration and turns a PC into a network server...

Servers:
A server is a computer that was made to use, or run NOS's!

Workstations:
Is a personal computer that is pretty much connected to a network, which can do stuff through applications and utilities.

Hosts:
It pretty much any network device that has a TCP/IP address

There are many kinds of Servers out there...

a few of them include

CD servers
E-mail servers
Fax servers
Print servers.

We'll discuss about CD Servers today as well.

It usually is alone, and consists of four or more, CD-ROM readers... could be up to 100 CD ROM readers.

E-mails Servers:
Is pretty much what e-mail is. there is a server that holds all the mail coming in from the internet.. and it just sends it out to the appropriate place!
Well that's all for today... more tomorrow!

Net +... computer basics

2007-09-09T20:45:00.000-07:00

I'm into computers and I'm a very technical guy! I love computers and I love using it! Today I'm gonna talk about the different types of networks.
1. A legacy network:
- In a legacy network all of the processing takes place at the central computer. That means that anything you do... on ur computer... it all is actually done on one main computer.
- It's very hard to get softwards and other products for legacy networks.. most of the applications are custom built... and it becomes pretty darn expensive.
2. Peer to Peer networks:

See the simple explaination of this network... is that everything... is done on each persons seperate computers... All of the files are in their own computers... Each computer has the ability to transfer files to one another... that's why it makes file sharing and using one printer easier!

The last one I will be talking about today is About a WAN

WAN:
WAN means its a Wide area network... it covers a really big geographical area, it can be as big as the national or international level. They have low to high speed links... this is a great type of server and is very useful int eh internet world! Hope this was helpful... More later!