Difference between VPN and VLAN?

Hi

VPN
more of you trying to access a different LAN(say LAN1) through a different Network ( LAN2)all together. You would be needing VPN access softwares (infact client and authentication) is needed for you to 'remotely' access the computers on the other networks.

where as in a VLAN, you pick few computers and create something called as a virtual LAN covering them . They need not be belonging to same LAN.The systems can be grouped on any of the layers. ie MAC layer/Network Layer/IP layer. This technology ( as far as I know) is put into telco companies replacing the normal ATM switches. Thus in telco sense, instead of VCI/VPI values, you would rather be talking about VLAN IDs.

Hi ,

Here are the details,

VLAN: It is group of computers that can have same broadcast domain. So the group of computers in that particular VLAN can directly talk to each other . It is generally used when you need to have separae set of computers to whom you can't directly talk from outside the VLAN and need special permission to get access to the resources in the VLAN generally via ACL (access control list).

VPN: It is used to communicate is a secure way in a non-secure environment. If you want your computer in one network to communicate to another computer in some snother network than they teh communicate has to happen over internet which is insecure medium. And hence teh packets are are transeferd over a encrypted channel (tunnel) between teh two computers so that person sitting on internet cannot sniff/decode the packet.