EEG, Enterprise Encryption Gateway is a layer2 encryption device that allows strong encryption and authentication of data across wireless medium. The client devices have client-side authentication/encryption software, and the EEGs are the encryption termination point in the network. Autonomous access points are placed downstream from the EEGs and may act as an 802.1X authenticator. Encryption techniques traditionally used with wireless have been very weak. WPA2/802.11i was only recently introduced to give the market standards-based strong authentication and encryption. Some vendors previously had taken it upon themselves to build stronger solutions based on the AES encryption algorithm. In the result, all EEGs are proprietary. Some of the EEGs offer high compression in order to offset latencies experienced by encryption. EEGs have an “encrypted” and “unencrypted” sides. The unencrypted side is the upstream backbone side where all of the network resources reside. Access points and client devices reside downstream on the encrypted side. Everything on the encrypted side of EEG is encrypted unless you, as the administrator, specifically configure it to be not. For example, you might configure AP management traffic to pass unencrypted only to the IP addresses of known APs on specific ports. Clients must use special software that communicates with the gateway to build secure tunnel. Users authenticate so they can gain access to upstream network resources. In this solution, like any other where the APs themselves are not specifically involved in the security protocol, the APs are left open to attack and hsould be secured as tightly as possible.

Example of EEG: airFortress AF2100 (http://www.keenansystems.com/airfortress_af2100_review.htm).

EWG, Enterprise Wireless Gateway is a device that can provide specialized authentication and connectivity for wireless clients. EWGs are appropriate for medium and large scale wireless environments providing a multitude of manageable wireless LAN services, such as client role-based access control, QoS, encrypted VPN tunneling, infrastructure management, and support for variety of back-end authentication systems. EWGs should have either Fast Ethernet or Gigabit Ethernet wired interfaces, due to large number of high-speed access points they support. The more access points EWG is supporting, the higher the uplink interface speed should be. Some EWGs may even provide PoE to downstream APs through multiple downlink ports. EWGs are usually configured through console ports (TELNET, SSH, HTTPS). Some EWGs are software-only implementations build around Open source operating systems such as OpenBSD. In this case manufacturer will provide you with the list of supported hardware which would be able to host you EWG environments. Many EWGs terminate PPTP, L2TP, SSH and IPsec VPN tunnels. Enterprise Wireless Gateways are so comprehensive that manufacturers highly recommend that you take the manufacturer's training courses before making a purchase so that the deployment of the device will go smoothly. Newer EEGs implement roaming too, so mobile users could move freely between APs while using encryption and not losing connectivity.

Example of EWG:  Vernier IS-6500p (http://www.verniernetworks.com/)

The differences are that these two devices are completely different, and there is no point comparing them at all. EEGs operate on layer2, while EWG operate on layer2 and up. EWGs are much more complicated and are responsible for far more functions than EEG is capable of.

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