Cisco Catalyst 3560-X Series, Software Configuration Manual

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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-25303-03
Chapter 1 Configuring Switch-Based Authentication
Configuring the Switch for Secure Socket Layer HTTP
You can remove this self-signed certificate by disabling the secure HTTP server and entering the no
crypto pki trustpoint TP-self-signed-30890755072 global configuration command. If you later
re-enable a secure HTTP server, a new self-signed certificate is generated.
Note
The values that follow TP self-signed depend on the serial number of the device.
You can use an optional command ( ip http secure-client-auth ) to allow the HTTPS server to request an
X.509v3 certificate from the client. Authenticating the client provides more security than server
authentication by itself.
For additional information on Certificate Authorities, see the “Configuring Certification Authority
Interoperability” chapter in the
Cisco IOS Security Configuration Guide, Release 12.4 .
CipherSuites
A CipherSuite specifies the encryption algorithm and the digest algorithm to use on a SSL connection.
When connecting to the HTTPS server, the client Web browser offers a list of supported CipherSuites,
and the client and server negotiate the best encryption algorithm to use from those on the list that are
supported by both. For example, Netscape Communicator 4.76 supports U.S. security with RSA Public
Key Cryptography, MD2, MD5, RC2-CBC, RC4, DES-CBC, and DES-EDE3-CBC.
For the best possible encryption, you should use a client browser that supports 128-bit encryption, such
as Microsoft Internet Explorer Version 5.5 (or later) or Netscape Communicator Version 4.76 (or later).
The SSL_RSA_WITH_DES_CBC_SHA CipherSuite provides less security than the other CipherSuites,
as it does not offer 128-bit encryption.
The more secure and more complex CipherSuites require slightly more processing time. This list defines
the CipherSuites supported by the switch and ranks them from fastest to slowest in terms of router
processing load (speed):
1. SSL_RSA_WITH_DES_CBC_SHA—RSA key exchange (RSA Public Key Cryptography) with
DES-CBC for message encryption and SHA for message digest
2.
SSL_RSA_WITH_RC4_128_MD5—RSA key exchange with RC4 128-bit encryption and MD5 for
message digest
3. SSL_RSA_WITH_RC4_128_SHA—RSA key exchange with RC4 128-bit encryption and SHA for
message digest
4.
SSL_RSA_WITH_3DES_EDE_CBC_SHA—RSA key exchange with 3DES and DES-EDE3-CBC
for message encryption and SHA for message digest
RSA (in conjunction with the specified encryption and digest algorithm combinations) is used for both
key generation and authentication on SSL connections. This usage is independent of whether or not a
CA trustpoint is configured.
Configuring Secure HTTP Servers and Clients
These sections contain this configuration information:
• Default SSL Configuration, page 1-51
•
SSL Configuration Guidelines, page 1-51
• Configuring a CA Trustpoint, page 1-51