An offerer MUST include this tag in the Require header field if the offer contains one or more "mandatory" strength-tags. If all the strength-tags in the description are "optional" or "none" the offerer MUST include this tag either in a Supported header field or in a Require header field. Defined in rfc 3312.

public const string precondition

Public Const precondition As String

public:
literal String^ precondition

static val mutable precondition: string