Specifies the type(s) of authentication, if any, to be negotiated with
the peer:
none No authentication is negotiated.
pap PAP negotiation only.
chap CHAP negotiation only.
papChap PAP negotiation is attempted first; if fails, attempt CHAP.
chapPap CHAP negotiation is attempted first; if fails, attempt PAP.
If authentication negotiation is not supported for this PPP interface,
then any attempt to explicitely set this object will result in a
notWritable error and it will be implicitily set to the DEFVAL on row
creation.
Setting this object to none(0) will set
juniPppLinkConfigAuthenticatorVirtualRouter object to an empty string.
This object returns a null(0) value on the get operation. New object
juniPppLinkConfigAuthentication2 will reflect the configured values.
Setting this object along with the juniPppLinkConfigAuthentication2 object
will return an inconsistentValue error.