Wednesday, February 24, 2010

How to wire your own ethernet cables

Required:
Cable - bulk Category (Cat) 5, 5e, 6 or higher cable
Wire Cutters - to cut and strip the cable if necessary
For Patch Cables:
RJ45 Plugs is an 8-position modular connector that looks like a large phone plug.
RJ45 Crimper
For Fixed Wiring:
RJ45 Jacks
110 Punch Down Tool

Recommended:
Wire Stripper
Cable Tester

About the Cable:
There are 2 kind of Cable UTP (Unshielded Twisted Pair) and Shield Twisted Pair cable with different Category , Two Type of Color Coding used i.e T568A and T568B.

T-568A Straight-Through Ethernet Cable

The TIA/EIA 568-A standard which was ratified in 1995, was replaced by the TIA/EIA 568-B standard in 2002 and has been updated since. Both standards define the T-568A and T-568B pin-outs for using Unshielded Twisted Pair cable and RJ-45 connectors for Ethernet connectivity. The standards and pin-out specification appear to be related and interchangeable, but are not the same and should not be used interchangeably.


T-568B Straight-Through Ethernet Cable

Both the T-568A and the T-568B standard Straight-Through cables are used most often as patch cords for your Ethernet connections.

If you require a cable to connect two Ethernet devices directly together without a hub or when you connect two hubs together, you will need to use a Crossover cable instead.

Subnet NEtworking

It not just easy,But not difficult too....

First Plan your requirement,i.e how many sub networks you need 2,3,4 according how many machine in each network. if you want around 60 machine in each network of 4 subnetwork. it very simple.

How calculation work

eg:
Decide the range of IP and Class of Network you wand A,B,C,D

Here i am taking the Range of Class " C" IP i.e 192.198.1.0-255
so my Subnet mask calculation will work like:
(255.255.255.0 - Standard Subnet mask)
Its converted into binary of eight decimal i.e 11111111.11111111.11111111.00000000(255.255.255.0)

The formula for figuring out the number of 'host' bits in a subnet mask is
2^n=(number of nodes ) (2^n means '2' to the power of 'n')
Since you know the number of nodes, you need to find 'n'.

Because you want 64 node(s), you want to leave 6 - '0' bits in the subnet mask since 64 = 2 ^ 6 (2x2x2x2x2x2).
This will give you the following subnet mask:

subnet mask: 11111111.11111111.11111111.11000000
Which is referred to as /26 or in dotted decimal notation as 255.255.255.192

So my SUBNET 1 will have IP Ranging from 192.168.0-63 were 0 is transmission ID and 63 Broadcast ID.
SUBNET 2 will have IP Ranging from 192.168. 64-127 were 64 is transmission ID and 127 Broadcast ID.
SUBNET 3 will have IP Ranging from 192.168.128-191 were 128 is transmission ID and 191 Broadcast ID.
SUBNET 4 will have IP Ranging from 192.168. 192-255 were 192 is transmission ID and 255 Broadcast ID.



easy online way to calculate:
http://www.t1shopper.com/tools/calculate/ip-subnet/

Tuesday, February 16, 2010

iPhone Troubleshooting

The below given details are just to have a self check i do not take any responsibility on this steps.... Perform it on your own interest.

1)Recharge issue:

The battery symbol below indicates that the
iPhone needs to be recharged.
use a high‐power USB port such as the one on a computer, or use an iPhone AC adapter.
DO not use the USB port on their keyboards because it may be a low‐power port and iPhone will not charge.
USE USB to charge iPhone. Firewire charging, through any third party device, is not supported by iPhone.
If the red part of the battery image flashes three times and then the screen goes black, it means that iPhone is not receiving power to charge.
If the iPhone battery is extremely low on power, the display may be blank for up to two minutes before one of the low battery images appears.

2)Restart Restarting the iPhone:

To turn iPhone off, press and hold the Sleep/Wake button until the red slider appears.
Slide your finger across the slider to turn off iPhone.
To turn iPhone on, press and hold the Sleep/Wake button until the Apple logo appears.
Does iPhone appear frozen?
To reset iPhone, press and hold the Sleep/Wake button and the Home button at the same time for at least 10 seconds.
During this time, a red ‘power off ‘ slider may appear and the screen may go black. Do not release Sleep/Wake and Home buttons until the Apple logo appears.

3)Reset Settings:

Tap Settings > General > Reset > Reset All Settings
Note: This will reset all settings. No data or media will be
deleted.

4)Restore:

Connect iPhone. When it appears in the Source list, click on Restore in the Summary tab using the latest version of iTunes.
Note: This will delete all media and data. All settings will be reset as well. If possible, sync iPhone with iTunes before restoring to backup most recent data and settings.