Category Archives: Computer Networking

How to add Users and Groups – CCProxy

Read previous post about CCProxy ->

To manage network flow through your proxy server, first you need to create filters and time schedules and then you have to create users or groups in CCProxy in order to make it work. To create a user or group, click “account” tab, Then in the “option” area change Permit Category  to the “Permit Only” then you will unlock options for creating users and groups. 

Click the “New” button and there will be a new window open for creating users and groups. To create groups, Put a tick on “As Group”. And you can see unnecessary options will be locked with that option clicked. To create user, follow the procedure without clicking that.

you can name your user first. then can choose to use password for each user and your users needs to know password to connect each time to your server. but this feature doesn’t seem to work really well with all the browsers. so you may have to keep in that mind. in such case, user has to open Internet Explorer and sign in to the network. It’s recommended to use IE for troubleshooting and stuff instead use other web browsers. To create user, you have to use an IP address / range, Mac Address or Host name. you can bind one of them or all of them as you wish. if you know the IP address or host name you can simply import MAC address by clicking the question mark on the side.

Next, you can add this user to group by clicking “Belongs to Group” option. But you have to create a group first for that.

These settings are can be applied to both users and groups.

Maximum Connections: It’s totally depend on the user’s workload and application that use. so it could be 1 or 100. If you really want limit maximum connections just monitor it first. However, by limiting maximum connections you can control abnormal traffic on your network.

Download Bandwidth: As it’s said you can control your each users Internet speed. However, it doesn’t intelligently distribute your Internet connection among users. setting up high bandwidth maybe make everyone Internet connection slow. So you have to fine tune your speed limit to get maximum performance. For the example, if you have 10 users with 10Mbps internet connection, you can add 10Mbps or more to each user to get maximum speed. but what’s going to happen is, first user put something to download and get full bandwidth while other users has to be wait till it’s done. So eventually it’s become a disaster. In other hand you could simply allocate 1Mbps for each. That could work if 1Mbps enough for one user and all users works on the same time. But in reality that’s not going to happen. If it’s less than 10 people on your network no one going to get advantage of it. Or you have 100 users, from 100Kbps, no one is getting work done. So that’s why you need a fine tune these values as your requirement needs. Just remember that you have to add those values in KB not KB. So keep that in mind.

Upload bandwidth: As download bandwidth you have to limit upload bandwidth. The important thing about this is always an Internet connection Upload speed is 2,3 times lower than download speed. In the next section you can block or allow types of connections as you wish. For the general use you don’t need to change anything on this.

Web filter / Time schedule : If you wish to use filter or enable time schedule on this user or group, you can use already created web filters and time schedules in drop down menu here. you can select one of them. if you haven’t create them you can read this post.

Auto disable at: As it says you can set a date and time to automatically disable to account. It’s good to add expire date for temporary users.

Bandwidth quota: You can allocate bandwidth for each user or group by this setting. If you use limited bandwidth Internet connection, this is an extremely useful option. For the example, if you set 512MB for 1 day, that user or group can use maximum download or upload data worth 512Mb for each day and if that exceeded, they have to wait till 1 day cycle reset to get new quota.

Left Time: Add left them in this section if required.

If the all options below are done, click the Save and OK. You will be able to see users and groups you added in the account manager. So you can add more users and groups for the CCProxy and when you have done, always remember to Export your setup to the.Ini file, so in case you had to do the same you can just simply import file with all the setting, users and filters.

How to use CCProxy to manage network connection

If you looking for something to manage your Internet connection in between small or medium scale network, proxy is one of ancient yet popular method to use. In the use of proxy CC-Proxy is one of best and easy to use application today for windows environment. You can download the application from following link.

Official Site : http://www.youngzsoft.net/ccproxy/

For the use this application in local environment you have to use the windows server machine or regular windows PC with 2 network adapters. you can also use the usb to rj45 adapter or wifi adapter.

After installation startup screen will look like this. so in order to use this we have to setup CC-Proxy before use.

first of all you must setup local IP and Proxy IP. usually CC-Proxy will automatically detect those but you have to check whether it’s correct or not. To the setup click “Options” icon and then configuration tab will appear.

Pretty much these setting doesn’t need to explain, this image shown here is custom setup, so it’s not necessary to be same as your setting. for now you can keep the defaults settings. Local IP address should be in auto detect mode and IP address shown here should be your proxy address. if it’s not, disable auto detect and manually put the correct address.

If you got this far, It’s pretty much done and in your local network users can use internet connection with proxy enable with their device. For above settings, client should use proxy address 192.168.0.154 and port 808 without user name and password. Also you can use “Monitor” icon to monitor network traffic going through your proxy server.

When the traffic starting to flow, you can see visual represent of network traffic in home tab. Green line represent your local area connection traffic and yellow line represent internet connection. Right click on the green mesh would open  “line chart options” that allows you to control maximum connections and bandwidth sizes.

However in this setup you only can monitor and limited control over the traffic. for more control and management you have to go for further settings with adding users to the network, which I explain in next post — >

 

All About IP Addressing part – 02

What is subnetting?

subnetting is a technique to break up a large network into smaller networks by sacrificing bit Host ID on the subnet mask to be used as a new Network ID.

example:

IP address 192.168.10.0 with a subnet mask 255.255.255.0 default is defined as a class C which means that IP address without subnetting a network address has only one fruit with 254 IP addresses that can be made (192.168.10.1 / 192.168.10.254).

Now we will divide the existing network into several the subnetwork using subnetting techniques by replacing a few bits of Host IDs that exist on the subnet mask with the number 1.

Before subnetting:

IP address: 192.168.10.0
Subnet Mask in Binary: 11111111.11111111.11111111.00000000
Subnet Mask in Decimal: 255.255.255.0

After Subnetting Being:

IP address: 192.168.10.0
Subnet Mask in Binary: 11111111.11111111.11111111.11000000
Subnet Mask in Decimal: 255.255.255.192

1. Determining the number of subnets (Sub Network) has formed. use the formula 2^n-2 where n is the number of 1 bits in the host ID that has been modified (11000000), the importance of the 2^n-2=2. so the IP 192.168.10.0 2 subnets obtained after subnetting new.

2. Determine the Number of Hosts of subnets, use the formula 2^h-2, h is the number 0 on the host ID bits (11000000), then on to 2^h-2=62, so there are 62 hosts persubnet. or in other words from two groups of the subnetworks, each the subnetwork can accommodate 62 computers with different IP addresses.

3. Determining Block subnet and IP address ranges Block subnet is obtained by subtracting 256 (2^8) with the numbers behind the subnet mask that has been modified, 256-192=64, then total the number of these reductions to the same subnet behind the numbers in order to get 64+64=128, 128+64=192. so the IP address that is applied to two new the subnetwork is 64:

192.168.10.64 / 192 168 127, the first subnet

192.168.10.128 / 192 168 191, the second subnet

4. Determining the IP Address that can be used. From the range of IP addresses on each subnet above are not everything can be used as a Host IP address:

Sub-network 1.

Subnet address: 192.168.10.64
The first Host Address: 192.168.10.65
Last Host Address: 192.168.10.126
Broadcast Address: 192.168.10.127

Sub-network 2.

Subnet address: 192.168.10.128
The first host address: 192.168.10.129
Last Host Address: 192.168.10.190
Broadcast Address: 192.168.10.191

Reason why we do subnetting..???

=>Reduce the density of traffic data: a LAN with 254 hosts will be more dense data traffic compared to a LAN with 64 hosts.

=>More the number of hosts, will be less of a chance each host in accessing data in a network which means reducing the performance of the network itself.

=>Simplification of managers: a remote network, the large number of computers that must connect will be made easier to manage when the network itself rather than have to be one big network.

All About IP Addressing part – 01

If you are reading this which means you are already know something about IP address in networking and now you are seeking something more. In below i’m going to explain everything I know about Ip address and I’ll explain all these in simple and easy to understand way which begin with basic level.

What is IP address?

In our regular world how our home address works? that’s the exact way Ip address works in networking world. If we have to send letter or parcel to  someone in far away we have to know his or her address to send it. like that in network world we use IP address to do same job as home address. In home address also contain particular structure. First we put name, then house number, then street address like this.. like that in IP addressing we use unique structure to make things works.

There are few IP address protocoles such as IPv4, IPv6. most commonly we use IPv4 and we are here first explain about it and latter we can go for IPv6. No matter what protocol is there are always 2 parts of it,
1. Host id
2. Network id

IP address = Network id + Host id

Host id is id of a device that other devices can connect to for access to resources. Host act like service provider. A network id is a id of device that are connected together to access and share resources provided by hosts. Both host and network devises can be any device such as computers, routers, switches or may be a printer.