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VLAN LAN Encryption?

Is it posible to encrypt traffic in a LAN?. Let me explain. I am renting two floors on a building, I have users (15 users) in floor 10 and  users (30 users) in floor 22. The connectivity between the two floors (uplink) is provided by the building, so they give me one Ethernet cable in floor 10 and another Ethernet cable in floor 22 (so I don’t own the uplink cable) . And I have to put a switch on each floor, it is a L2 topology. What I want to do is secure the communications between the two floors. Is it possible to encrypt the traffic going through the uplink?.  I have to buy the switches, so I’m open to suggestions to buy a hardware that can do what I need. Thanks for any suggestion. Gonzalo

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Hall of Fame Super Blue

VLAN LAN Encryption?

You can purchase encryptors.  You deploy them so you connect the two encryptors together using the inter-floor uplinks.  Then you connect the other ethernet interface to your switches.  So traffic from one floor to the other is totally secure.

Because copper is easily "tapped", you can still run the risk of someone "listening" and collecting packets for future decryption.  But this scenario is really a far-fetched.

Community Member

VLAN LAN Encryption?

Leolaohoo, any advise on a particular equipment?

VIP Super Bronze

VLAN LAN Encryption?

You can use a device like in this link.  Hardware encryption devices are not usually cheap and most of the time they are capable of layer-3 with static routes and don't understand vlans. 

This device appears to do layer-2 with vlans.

If all possible, try using software encryption between the hosts.


Hall of Fame Super Blue

VLAN LAN Encryption?

Google for "ethernet encryption".

Take note that there's a major price difference between encryption appliance that can do 10, 100, 1000 and 10Gb.  So choose wisely.  Another thing, make sure the manufacturer quotes the speed supported to be FULL duplex and FULL encryption.  Some manufacturer will say that the blah-blah model can support up to 100 mbps but what they won't tell you is that the value of "100 mbps" is calculated at HALF duplex and no encryption. 

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