Wimax standards and Security The Wimax

SHA-1 SHA computes a hash value of 160 bits (20 bytes) out of an arbitrary- sized binary document
SS wireless subscriber station
TEK traffic encryption key, the key used to encrypt the WiMAX traffic
WiMAX worldwide interoperability for microwave access, a technology spec- ified by the IEEE 802.16 standards to enable the delivery of last mile wireless broadband access
WiMAX security sublayer a protocol set defined in the WiMAX MAC layer.
It secures SSs, BSs, and transmission connections
X.509 an ITU-T standard for public key infrastructure (PKI)
X.509 certificate a digital certificate structured according to the X.509 guide- lines
XOR exclusive-or



Appendix I: X.509 Certificate
The X.509 certificate is specified in IETF RFC 3280 (Internet X.509 public key infrastructure: certificate and certificate revocation list (CRL) profile). An X.509v3 certificate consists of three parts:

1. 
   A certificate body containing
   
   • 
     The version number (currently, v3, v2, and v1 are also possible)
     
   • 
     A unique serial number assigned by the responsible certification authority (CA)
     

• 
  The declaration of the signature algorithm to be used to sign the certificate
  
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  The ID of the CA that issued and signed the certificate
  
• 
  The validity period (not valid before/not valid after)
  
• 
  The subject (user) ID
  
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  The public key of the subject (user), and
  
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  Any number of optional v2 or v3 extensions
  
1. 
   The definition of the signature algorithm used by the CA to sign the certificate
   
2. 
   The signature guaranteeing the authenticity of the certificate, consisting of the hashed certificate body encrypted by the CA’s private key
   

X.509 certificates are binary encoded using the destinct encoding rules (DER). The size of a DER-encoded X.509v3 certificate containing a 1024-bit RSA public key is usually between 900 and 1500 bytes, depending on the length of the subject (user) ID, issuer IDs, and the version number being used.