• go to start→ setting
• add & remove
• change/ remove, tick on remove.
3.9 VIRTUAL PRIVATE NETWORK (VPN)
A virtual private network is used to convert public network address to private network. All the clients of VPN dial to public IP address of VPN server and receive private IP from virtual VPN dynamic host protocol (DHCP).in VPN one can have multiple virtual connections to a single IP address. This way ,one network card can host several inbound connections, rather than require a modem and telephone line for each simultaneous remote user.
Fig 15 : scenario of VPN server
Using VPN server we can connect many private networks to internet services i.e the remote connection. We can create a private network through public network, we can use firewall for security and data encryption in VPN server.
3.9.1 VPN components
(i) VPN server (ii) VPN Clients (iii) WAN Option (iv) Security Options VPN Server
VPN server, serve as the end points of a VPN connection. When configuring a VPN server, you can allow access to just that server, or pass traffic through VPN server so that the remote user gain access the resources of the entire network.
VPN Client
VPN clients establish connection to VPN server. They can also be routers that obtain the router-to-router secure connection. VPN client software is included in all the modern window operating systems, including Window 2003 server. Router-to router VPN connection can be made from computers running server2003 and Windows 2000
running Routing and Remote Access. Additionally, any client that support PPTP or L2TP connections can be VPN clients of a window server 2003 system.
WAN Options
These provide the physical mechanism for passing data back and forth. These connections typically include such similar network technologies such as T1or frame relay. In order for VPN connections to be successful, the VPN client and VPN server must be connected to each other using either permanent WAN connection or by dialing into an internet server provider (ISP).
Security Options
Since a VPN uses a network that is generally open to the public, it is important that the data passed over the connection remain secure. To aid with secure communication routing and remote access supports such security measure as logon and domain security, data encryption, smart cards, IP packet filtering and caller ID.
3.9.2 Types of VPN
(i) PPTP (Point to Point Tunneling Protocol )
(ii) L2TP (Layer 2 Tunneling Protocol) according to CCNA. Point to Point Tunneling Protocol (PPTP)
PPTP is Microsoft’s legacy protocol for supporting VPN. It was developed in conjunction with other communications companies such as Robotics as an extension to the PPP protocol. PPTP encapsulates IP or IPX packets inside of PPP datagram’s. This means that you can remotely run programs that are dependent upon particular network protocols. One of the keys to remember about PPTP is that the protocol provides encryption capabilities, making it much safer to send information over nonsecure networks.
Layer Two Tunneling Protocol (L2TP)
L2TP is a standard based encapsulation protocol with roughly the same functionality as a Point-to-Point Tunneling Protocol (PPTP). One of the key differences
between Window’s server 2003 implementation of L2TPand it cousin PPTP is that L2TPis designed to run natively over IP networks only. This implementation of L2TP does not support native tunneling over X.25, frame relay, or ATM networks. Like PPTP, L2TPencapsulates Point-to-Point Protocol (PPP) frames, which then encapsulate IP or IPX protocols, allowing users to remotely run programs that are dependent on specific network protocols . But unlike the PPTP protocol, L2TP does not provide encryption of the data. For data security L2TPrelies on the services of another standards- based protocol, IPSec.
3.9.3 How to configure VPN
• start→administrative tools
• Routing and Remote access
• Right click on computer name configure and enable Routing and Remote access
• next→ select remote access (dial up or VPN)
• next→ VPN→ next
• select LAN card which is connected to internet (172.15.15.50) public IP
• disable enable security → next
• from a specific range of address→ next→new
• enter the required range
• ok→next→ no radius
• next→ finish
3.9.4 Create users in VPN server
• open user properties→ dial in → allow access
• apply→ ok
3.9.5
Working on Client Side
• Right click on My Network Places→ properties
• Connect to network at my work place→ next
• Virtual private network connection→ next
• Enter company name (abc)→ next
• Enter public IP address of VPN server→ next
• Any one use →next
• finish
3.10
ROUTING
It is a process of transferring information through an inter network i.e from one network to another. Routing connect different networks having ID help in process of routing. The dial-in properties also allow for specific IP address to be assigned to a user. This is the only way in Window Server 2003 that you can assign a specific IP to a user. To assign a specific IP to a user, check the box next to assign A Static IP Address and enter a valid IP in the space provided. Static routing can also be specified as per user. By defining static routes, users can be limited to only specific parts of networks.
In an internetwork a router must then about all the networks present in the for effort websites, there are hardware routers like CISCO. Even win 2003 server computer configured as router. In simple words Router is a computer with two network cards. These two network cards, then, are attached to two different logical IP networks. The routing table helps direct traffic that is passed through the router.
Now when there is a router, also there is a routing table, there is a need to configure the router in order for that router to pass along traffic to the proper network. There are two ways the routing table can be built and modified: either manually or automatically.
3.10.1 Types of Routing
(i) Static Routing (ii) Dynamic Routing