D-Link DES-3028 User Manual - Ssl

DES-3028 DES-3028P DES-3052 DES-3052P Layer 2 Fast Ethernet Managed Switch 

SSL 

Secure Sockets Layer or SSL is a security feature that will provide a secure communication path between a host and client through 

the use of authentication, digital signatures and encryption. These security functions are implemented through the use of a 

ciphersuite, which is a security string that determines the exact cryptographic parameters, specific encryption algorithms and key 

sizes to be used for an authentication session and consists of three levels: 

1.  Key Exchange: The first part of the ciphersuite string specifies the public key algorithm to be used. This switch utilizes 

the Rivest Shamir Adleman (RSA) public key algorithm and the Digital Signature Algorithm (DSA), specified here as the 

DHE DSS Diffie-Hellman (DHE) public key algorithm. This is the first authentication process between client and host as 

they “exchange keys” in looking for a match and therefore authentication to be accepted to negotiate encryptions on the 

following level.  

2.  Encryption: The second part of the ciphersuite that includes the encryption used for encrypting the messages sent 

between client and host. The Switch supports two types of cryptology algorithms: 

Stream Ciphers – There are two types of stream ciphers on the Switch, RC4 with 40-bit keys and RC4 with 128-

bit keys. These keys are used to encrypt messages and need to be consistent between client and host for optimal 

use.  

• 

•  CBC Block Ciphers – CBC refers to Cipher Block Chaining, which means that a portion of the previously 

encrypted block of encrypted text is used in the encryption of the current block. The Switch supports the 3DES 

EDE encryption code defined by the Data Encryption Standard (DES) to create the encrypted text. 

3.  Hash Algorithm: This part of the ciphersuite allows the user to choose a message digest function which will determine a 

Message Authentication Code. This Message Authentication Code will be encrypted with a sent message to provide 

integrity and prevent against replay attacks. The Switch supports two hash algorithms, MD5 (Message Digest 5) and SHA 

(Secure Hash Algorithm). 

These three parameters are uniquely assembled in four choices on the Switch to create a three-layered encryption code for secure 

communication between the server and the host. The user may implement any one or combination of the ciphersuites available, 

yet different ciphersuites will affect the security level and the performance of the secured connection. The information included in 

the ciphersuites is not included with the Switch and requires downloading from a third source in a file form called a certificate. 

This function of the Switch cannot be executed without the presence and implementation of the certificate file and can be 

downloaded to the Switch by utilizing a TFTP server. The Switch supports SSLv3 and TLSv1. Other versions of SSL may not be 

compatible with this Switch and may cause problems upon authentication and transfer of messages from client to host. 

Download Certificate 

This window is used to download a certificate file for the SSL function on the Switch from a TFTP server. The certificate file is a 

data record used for authenticating devices on the network. It contains information on the owner, keys for authentication and 

digital signatures. Both the server and the client must have consistent certificate files for optimal use of the SSL function. The 

Switch only supports certificate files with .der file extensions. The Switch is shipped with a certificate pre-loaded though the user 

may need to download more, depending on user circumstances. 

Ciphersuite 

This window will allow the user to enable SSL on the Switch and implement any one or combination of listed ciphersuites on the 

Switch. A ciphersuite is a security string that determines the exact cryptographic parameters, specific encryption algorithms and 

key sizes to be used for an authentication session. The Switch possesses four possible ciphersuites for the SSL function, which are 

all enabled by default. To utilize a particular ciphersuite, disable the unwanted ciphersuites, leaving the desired one for 

authentication.  

When the SSL function has been enabled, the web will become disabled. To manage the Switch through the web based 

management while utilizing the SSL function, the web browser must support SSL encryption and the header of the URL must 

begin with https://. (Ex. https://10.90.90.90) Any other method will result in an error and no access can be authorized for the web-

based management. 

To view the windows for Download Certificate and Ciphersuite, click Security > SSL: 

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