Take the computer for which you are making server, insert the second LAN in that computer.
Connect your internet connection into the first LAN (inbuilt) on that computer.
Enter the IP address which you got from your ISP and check whether you can able to use internet on that system.
Now make sure that the second LAN is detected and is showing Unplugged.
Open properties of the first LAN (inbuilt LAN) and then go to "Advanced" option which is available on the top, then check both the boxes and say ok. and close everything.
Now take an Internet cable which is crimped on both the sides with same colors of wires.
Connect one end to the second LAN and the other end to the switch.
Now open your second LAN properties and go to the TCP/IP properties and there enter IP address as (192.168.0.1) or anything you wish Subnet Mask (255.255.255.0)
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and the gateway as (192.168.0.1).
NOTE: - THE GATEWAY SHOULD BE SAME AS THE IP ADDRESS ONLY FOR
THE SERVER.
9. Now open click on the switch and you will get a notification on your server saying that "Local
Area Connection 2" is connected.
10. Now take an Internet cable and one end of that cable should be in any one port of the Switch and the other should be in the second computer.
11. Now you will get a notification that you are connected to internet, open the LAN properties and enter the IP address as (192.168.0.2) subnet mask and gateway should be same as server. say ok
12. You will now be able to browse Internet on that particular system now.
13. Do the same with the rest of the systems.
NOTE: - THE IP ADDRESSES SHOULD NOT BE USED SAME FOR TWO
SYSTEMS. SO BETTER GO WITH 192.168.0.1 (FOR SERVER) 192.168.0.2 (1ST CLIENT)
192.168.0.3(SECOND CLIENT) AND SO ON.......BUT THE SUBNET MASK AND
GATEWAYS SHOULD BE SAME FOR ALL THE CLIENT AND SERVER SYSTEM.
And one more thing should be kept in mind that is you won’t be able to browse internet unless or until your Server Pc is turned ON.
A virtual private network (VPN) is a network that uses primarily public telecommunication infrastructure, such as the Internet, to provide remote offices or traveling users access to a central organizational network.
VPNs typically require remote users of the network to be authenticated, and often secure data with encryption technologies to prevent disclosure of private information to unauthorized parties.
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VPNs may serve any network functionality that is found on any network, such as sharing of data and access to network resources, printers, databases, websites, etc. A VPN user typically experiences the central network in a manner that is identical to being connected directly to the central network.
VPN technology via the public Internet has replaced the need to requisition and maintain expensive dedicated leased-line telecommunication circuits once typical in wide-area network installations.
VPN Connecting Two Remote Sites across the Internet
PPTP-based VPN and L2TP/IPSec-based VPN connection properties are described in the following sections.
Encapsulation
VPN technology provides a way of encapsulating private data with a header that allows the data to traverse the network.
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Authentication
There are three types of authentication for VPN connections:
User authentication
For the VPN connection to be established, the VPN server authenticates the VPN client attempting the connection and verifies that the VPN client has the appropriate permissions. If mutual authentication is being used, the VPN client also authenticates the
VPN server, providing protection against masquerading VPN servers.
The user attempting the PPTP or L2TP/IPSec connection is authenticated using Point-to-
Point (PPP)-based user authentication protocols such as Extensible Authentication
Protocol-Transport Layer Security (EAP-TLS), Microsoft Challenge-Handshake
Authentication Protocol (MS-CHAP), Microsoft Challenge-Handshake Authentication
Protocol version 2 (MS-CHAP v2), Shiva Password Authentication Protocol (SPAP), and
Password Authentication Protocol (PAP). For PPTP connections, you must use EAP-
TLS, MS-CHAP, or MS-CHAP v2. EAP-TLS using smart cards or MS-CHAP v2 is highly recommended, as they provide mutual authentication and are the most secure methods of exchanging credentials.
Computer authentication with L2TP/IPSec
By performing computer-level authentication with IPSec, L2TP/IPSec connections also verify that the remote access client computer is trusted.
Data authentication and integrity
To verify that the data being sent on an L2TP/IPSec VPN connection originated at the other end of the connection and was not modified in transit, L2TP/IPSec packets include a cryptographic checksum based on an encryption key known only to the sender and the receiver.
Data Encryption
Data can be encrypted for protection between the endpoints of the VPN connection. Data encryption should always be used for VPN connections where private data is sent across a public network such as the Internet. Data that is not encrypted is vulnerable to unauthorized interception. For VPN connections, Routing and Remote Access uses
Microsoft Point-to-Point Encryption (MPPE) with PPTP and IPSec encryption with
L2TP.
Address and Name Server Allocation
When a VPN server is configured, it creates a virtual interface that represents the interface on which all VPN connections are made. When a VPN client establishes a VPN
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connection, a virtual interface is created on the VPN client that represents the interface connected to the VPN server. The virtual interface on the VPN client is connected to the virtual interface on the VPN server, creating the point-to-point VPN connection.
The virtual interfaces of the VPN client and the VPN server must be assigned IP addresses. The assignment of these addresses is done by the VPN server. By default, the
VPN server obtains IP addresses for itself and VPN clients using the Dynamic Host
Configuration Protocol (DHCP). Otherwise, a static pool of IP addresses can be configured to define one or more address ranges, with each range defined by an IP network ID and a subnet mask or start and end IP addresses.
Name server assignment, the assignment of Domain Name System (DNS) and Windows
Internet Name Service (WINS) servers to the VPN connection, also occurs during the process of establishing the VPN connection.
An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."
The designers of the Internet Protocol defined an IP address as a 32-bit number and this system, known as Internet Protocol Version 4 (IPv4), is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses, a new addressing system (IPv6), using 128 bits for the address, was developed in 1995, standardized as RFC 2460 in 1998, and is being deployed worldwide since the mid-2000s.
IP addresses are binary numbers, but they are usually stored in text files and displayed in human-readable notations, such as 172.16.254.1 (for IPv4)
There were five IP address classes in use before the majority of industry switched to classless routing. There were A, B, C, D, and E. Class A addresses were used for networks with a very large number of total hosts. Class B was designed for use on medium to large networks, and C for small local area networks (LANs). Class D and E were set aside for multicast and experimental purposes. In the following table, the four octets that make up an IP address (a, b, c, and d respectfully) are displayed in how they were distributed in classes A, B, and C. classes A, B, and C.
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The allocation of 4,294,967,296 Addresses
Class IP Address
A
B
C a.b.c.d a.b.c.d a.b.c.d
Network ID Host ID a a.b a.b.c b.c .d c.d d
In a class A address, the first octet is the network portion, so the class A address of,
10.1.25.1, has a major network address of 10. Octets 2, 3, and 4 (the next 24 bits) are for the hosts. Class A addresses are used for networks that have more than 65,536 hosts
(actually, up to 16,581,375 hosts!).
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In a class B address, the first two octets are the network portion, so the class B address of,
172.16.122.204, has a major network address of 172.16. Octets 3 and 4 (the next 16 bits) are for the hosts. Class B addresses is used for networks that have between 256 and
65,536 hosts.
In a class C address, the first three octets are the network portion. The class C address of,
193.18.9.45, has a major network address of 193.18.9. Octet 4 (the last 8 bits) is for hosts.
Class C addresses are used for networks with less than 254 hosts.
After the invention of the Domain Name System (DNS), industry realized that the use of
IP address classes would limit the scalability of the Internet. As a result, the IETF published RC 1518 and 1519 in 1993 to define the classless method of routing IPv4 data packets.
The most recent definition of the standard occurred in 2006 under RFC 4632. Classless
IP addressing was introduced as a more efficient means to make use of the IP address space when compared to Classful addressing. In classless addressing, the IP address is treated as a 32 bit stream where the boundary between the network identification and host can be at any of the bit positions.
The network portion of the address is determined by the number of 1’s that are in the subnet mask being applied to the address. A subnet mask is used locally on the hosts connected to the network and are never transmitted in an IPv4 data packet or datagram.
All of the hosts on the same network are configured to use the same subnet mask with the host section of the IP address being unique to the host.
The classless version of address is referred to as Classless Inter-Domain Routing (CIDR) and allows networks to be divided into different-sized subnets. The system avoids wasting IP addresses through the use of the subnet mask.
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Internet Address: An IP address of the system is called logical address.
Physical address: Each system having a NIC (Network Interface Card) through which two systems physically connected with each other with cables.
Port Address: There are many applications running on the computer. Each application run with a port no. on the computer.
Port address is the port being used ... for example... if you open Google... you computer would dynamically create a port and the request is set over that port... lets say 3999,
Now we all know http work on port 80 sot the request with be sent to port 80
IP address it the logical address of you computer and physical address it the mac address which is physically printed when a NIC card is being manufactured.
Open command prompt netstat -a and ipconfig /all that will give you some idea
Through logical address the system identifies a network (source to destination). After identifying the network physical address is used to identify the host on that network. The port address is used to identify the particular application running on the destination machine.
Logical Address: An IP address of the system is called logical address. This address is the combination of Net ID and Host ID. This address is used by network layer to identify a particular network (source to destination) among the networks. This address can be changed by changing the host position on the network. So it is called logical address.
Physical address: Each system having a NIC (Network Interface Card) through which two systems physically connected with each other with cables. The address of the NIC is called
Physical address or mac address. This is specified by the manufacture company of the card. This address is used by data link layer.
Port Address: There are many applications running on the computer. Each application run with a port no.(logically) on the computer. This port no. for application is decided by the Karnal of the
OS. This port no. is called port address.
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The IP Address of all hosts connected to the Internet are divided into two parts-:
1. The Network ID (NETID)
2. The Host ID (HOSTID)
The number of octets or bits allocated to the netid and the hostid parts depends on the class or the range to which the IP Address belongs. For Example, if an IP Address belongs to Class A, then the first 8 bits are allocated to the netid part, while the remaining 24 bits are allocated to the hostid part.
To find the Network ID and Host ID from an IP address you need to use a Subnet Mask. The address 220.43.6.8 is a class C IP address (Since the range of Class C address is 192.0.0.0 to
223.255.255.255).
The standard default mask for class C is 255.255.255.0
Hence, network address = 220.43.6.8 AND 255.255.255.0 = 220.43.6
The fixed portion of a unicast address prefix includes the bits up to and including the prefix length that have a defined value. The variable portion of a unicast address prefix includes the bits beyond the prefix length that are set to 0. Subnetting is the use of the variable portion of a unicast address prefix to create address prefixes that are more efficient (that waste fewer possible addresses) for assignment to the subnets of an organization network.
Subnetting for IPv4 was originally defined to make better use of the host bits for Class A and Class
B IPv4 public address.
A supernet is an Internet Protocol (IP) network that is formed from the combination of two or more networks (or subnets) with a common Classless Inter-Domain Routing (CIDR) prefix.
The new routing prefix for the combined network aggregates the prefixes of the constituent networks. It must not contain other prefixes of networks that do not lie in the same routing path.
The process of forming a supernet is often called supernetting, route aggregation, or route summarization.
Supernetting within the Internet serves as a preventative strategy to avoid topological fragmentation of the IP address space by using a hierarchical allocation system that delegates control of segments of address space to regional network service providers. This method facilitates regional route aggregation.
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The benefits of supernetting are conservation of address space and efficiencies gained in routers in terms of memory storage of route information and processing overhead when matching routes.
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