-type property_group() :: [property_parm()].

-type property_groups() :: [property_group()].

-type property_parm() :: #'PropertyParm'{name :: term(), value :: term(), extraInfo :: term()}.

-type sdp() ::
    sdp_o() |
    sdp_s() |
    sdp_i() |
    sdp_u() |
    sdp_e() |
    sdp_p() |
    sdp_c() |
    sdp_b() |
    sdp_k() |
    sdp_a() |
    sdp_a_rtpmap() |
    sdp_a_ptime() |
    sdp_z() |
    sdp_t() |
    sdp_r() |
    sdp_m().

-type sdp_a() :: #megaco_sdp_a{attribute :: term(), value :: term()}.

-type sdp_a_fmtp() :: #megaco_sdp_a_fmtp{format :: term(), param :: term()}.

-type sdp_a_ptime() :: #megaco_sdp_a_ptime{packet_time :: term()}.

-type sdp_a_quality() :: #megaco_sdp_a_quality{quality :: term()}.

-type sdp_a_rtpmap() ::
    #megaco_sdp_a_rtpmap{payload_type :: term(),
                         encoding_name :: term(),
                         clock_rate :: term(),
                         encoding_parms :: term()}.

-type sdp_b() :: #megaco_sdp_b{bwtype :: term(), bandwidth :: term()}.

-type sdp_c() ::
    #megaco_sdp_c{network_type :: term(), address_type :: term(), connection_addr :: term()}.

-type sdp_e() :: #megaco_sdp_e{email :: term()}.

-type sdp_i() :: #megaco_sdp_i{session_descriptor :: term()}.

-type sdp_k() :: #megaco_sdp_k{method :: term(), encryption_key :: term()}.

-type sdp_m() ::
    #megaco_sdp_m{media :: term(),
                  port :: term(),
                  num_ports :: term(),
                  transport :: term(),
                  fmt_list :: term()}.

-type sdp_o() ::
    #megaco_sdp_o{user_name :: term(),
                  session_id :: term(),
                  version :: term(),
                  network_type :: term(),
                  address_type :: term(),
                  address :: term()}.

-type sdp_p() :: #megaco_sdp_p{phone_number :: term()}.

-type sdp_property_group() :: [sdp_property_parm()].

-type sdp_property_groups() :: [sdp_property_group()].

-type sdp_property_parm() :: sdp() | property_parm().

-type sdp_r() ::
    #megaco_sdp_r{repeat_interval :: term(), active_duration :: term(), list_of_offsets :: term()}.

-type sdp_s() :: #megaco_sdp_s{name :: term()}.

-type sdp_t() :: #megaco_sdp_t{start :: term(), stop :: term()}.

-type sdp_u() :: #megaco_sdp_u{uri :: term()}.

-type sdp_v() :: #megaco_sdp_v{version :: term()}.

-type sdp_z() :: #megaco_sdp_z{list_of_adjustments :: term()}.