The Authentication Type used for this interface. This
field is valid only when the Authentication Present bit is set.
The 'none' indicates the session doesn't support
authentication.
The 'simple' indicates the session supports simple
password authentication.
The 'md5' indicates the session supports Keyed MD5
authentication.
The 'mmd5' indicates the session supports
Meticulous Keyed MD5 authentication.
The 'sha1' indicates the session supports Keyed SHA1
authentication.
The 'msha1' indicates the session supports
Meticulous Keyed SHA1 authentication.