> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/voice-and-media/configure-fax-passthrough.md). # Configure Fax Passthrough > **Applies to:** Tmedia 3.0, 3.2, 3.3; SBC 3.1, 3.3 **To enable passthrough:** 1. Select **Profiles** from the navigation menu. ![ConfigureFaxPassthrough 0](https://docs.telcobridges.com/w/images/8/8e/ConfigureFaxPassthrough_0.png) 2. Click **Create New Profile** ![ConfigureFaxPassthrough 1](https://docs.telcobridges.com/w/images/3/37/ConfigureFaxPassthrough_1.png) 3. Enter a name for the Fax Profile. * Click **Fax/Modem Relay** to expand the view. ![ConfigureFaxPassthrough 2 A](https://docs.telcobridges.com/w/images/a/a7/ConfigureFaxPassthrough_2_A.png) 4. Configure the settings: * Set **Detection Mode** to Standard. * Set **Relay Mode** to Passthrough. * Check the **Switch to FAX relay upon CNG tone** option. * Set **Detection type** to "Silence Suppression off" * Verify the Codec is the same as the remote end. * Click **Create** ![ConfigureFaxPassthrough 3](https://docs.telcobridges.com/w/images/a/a3/ConfigureFaxPassthrough_3.png) 5. Verify that the **Profile was successfully created** message is displayed. ![ConfigureFaxPassthrough 4](https://docs.telcobridges.com/w/images/b/bb/ConfigureFaxPassthrough_4.png) **Path** ``` /configurations/@[configuration_name]/profiles/@[profile_name] ``` **Parameters (text)** ``` /configurations/@[configuration_name]/profiles/@[profile_name] name = "@[profile_name]" /configurations/@[configuration_name]/profiles/@[profile_name]/call_transfer_options call_transfer_mode = "Relay" call_transfer_timeout = "1 minute" terminate_transferor_immediately = false /configurations/@[configuration_name]/profiles/@[profile_name]/ivr_record vad_enabled = false vad_noise_floor_level = "-30" /configurations/@[configuration_name]/profiles/@[profile_name]/lnp_options incoming_lnp_mode = "Terminate LNP" outgoing_lnp_mode = "No LNP insertion" /configurations/@[configuration_name]/profiles/@[profile_name]/mlpp_options look_ahead_for_busy = "LFB allowed" network_identity = 0 outgoing_mode = "No MLPP insertion" precedence_level = "PL flash override" service_domain = 0 /configurations/@[configuration_name]/profiles/@[profile_name]/tdm_line subject_to_electric_hybrid_echo = true /configurations/@[configuration_name]/profiles/@[profile_name]/tones_and_call_progress_options busy_tone_max_duration = "30 seconds" default_digit_duration = 100 default_interval_between_digits = 60 generate_busy_tone = false tone_definition_profile = "USA-Canada" /configurations/@[configuration_name]/profiles/@[profile_name]/tones_and_call_progress_options/early_media_relay_and_ring_tone_generation connect_full_duplex_during_early_media = false delay_before_connecting_early_media = "0 millisecond" incoming_calls_early_media_mode = "Forward from outgoing to incoming call" outgoing_calls_early_media_mode = "Automatic early media detection" ring_tone_starting_state = "Call Alerted" /configurations/@[configuration_name]/profiles/@[profile_name]/custom_cause_maps /configurations/@[configuration_name]/profiles/@[profile_name]/tdm /configurations/@[configuration_name]/profiles/@[profile_name]/tdm/ss7 default_backward_call_indicator = "0x5404" default_backward_call_indicator_enforce_mask = "0x0000" default_forward_call_indicator = "0x2001" default_forward_call_indicator_enforce_mask = "0x0000" dont_forward_early_acm = false force_backward_call_indicator_in_anm = false forward_application_transport_ie = false forward_call_cpg_hold_retrieval = true forward_call_indicator_international = false forward_call_suspend_resume = true hop_counter_ie_handling = "Decrement and forward" isup_release_location = "Private network LU" relay_release_location_from_other_leg = false send_charge_number_ie_in_iam = false /configurations/@[configuration_name]/profiles/@[profile_name]/tdm/ss7_or_isdn always_send_alerting = false cnam_collection_timeout = "1 second" cnam_using_alternate_methods = false colr = false information_transfer_capability = "Relay" network_specific_facilities_ie = "" send_connected_number_ie = false send_display_ie = false support_2_calling_number_ie = false /configurations/@[configuration_name]/profiles/@[profile_name]/voip /configurations/@[configuration_name]/profiles/@[profile_name]/voip/fax_modem_relay detection_mode = "Standard" enable_early_fax_modem_tone_detection = false enable_fax_modem_relay = false expected_cng_tones = 1 fax_modem_tones_detection_duration = "30 seconds" modem_vs_fax_distinction_timeout = "0 millisecond" relay_mode = "T.38" switch_to_fax_relay_upon_cng_tone = true switch_to_passthrough_upon_bell_ans = true /configurations/@[configuration_name]/profiles/@[profile_name]/voip/fax_modem_relay/fax_modem_passthrough_parameters codec = "PCMU" detection_type = "NONE" force_v152_vbd = false jitter_buffer_depth = 40 packet_duration = "20ms" support_v152_vbd = false use_nse = false /configurations/@[configuration_name]/profiles/@[profile_name]/voip/fax_modem_relay/t38_parameters fill_bit_removal = false max_bitrate = "14400" redundancy_count = 0 transmission_level_minus_dbm = 10 use_v34 = false /configurations/@[configuration_name]/profiles/@[profile_name]/voip/rtp_and_audio clear_channel_packet_duration = "20ms" codec_g726_aal2_format = false drop_call_thresholds_no_rx_packets = "0 second" enable_mos_calculation = false vad_noise_floor_level = "-45" /configurations/@[configuration_name]/profiles/@[profile_name]/voip/rtp_and_audio/echo_cancellation echo_cancellation_enabled = true enable_coefficient_update = true enable_dc_removal_filter = true gain_power_level = "0" non_linear_processor_tune_option = "Normal" /configurations/@[configuration_name]/profiles/@[profile_name]/voip/rtp_and_audio/jitter_buffer initial_depth = 20 max_depth = 200 min_depth = 20 smooth_deletion = true /configurations/@[configuration_name]/profiles/@[profile_name]/voip/rtp_and_audio/packet_network packet_loss_concealment = true type_of_service = 0 /configurations/@[configuration_name]/profiles/@[profile_name]/voip/rtp_and_audio/rtcp rtcp_enabled = false sdes_cname = "" transmission_interval = "5 seconds" use_xrtcp = false /configurations/@[configuration_name]/profiles/@[profile_name]/voip/rtp_and_audio/tdm_volume_control rx_gain_level = 0 tx_gain_level = 0 /configurations/@[configuration_name]/profiles/@[profile_name]/voip/sdp force_fax_tones_as_telephony_event = false profile_sdp_description = "m=audio 0 RTP/AVP 0 8 101\r\na=rtpmap:101 telephone-event/8000" /configurations/@[configuration_name]/profiles/@[profile_name]/voip/sip custom_sip_bye_headers = "P-RTP-Stat: PS=@{Stat:Rtp:Tx:IPPackets}, OS=@{Stat:Rtp:Tx:IPBytes}, PR=@{Stat:Rtp:Rx:IPPackets}, OR=@{Stat:Rtp:Rx:IPBytes}, PL=@{Stat:Rtp:Rx:Error:LostPackets}, JI=@{Stat:Rtcp:Jitter}, LA=@{Stat:Rtcp:RoundTripDelay}, DU=@{CallDuration}" custom_sip_bye_headers_enabled = false detect_180_with_sdp_as_early_media = true dont_forward_183_progress = false dtmf_relay_scheme = [ "Relay DTMF according to RFC2833", "Relay DTMF using SIP INFO messages", "Relay DTMF in band" ] enable_sip_custom_headers = false forward_sip_hold_type = "SS7 Remote Hold/Retrieval" forward_ss7_cpg_hold_retrieval = true forward_ss7_suspend_resume = true max_forwards_handling = "Decrement and forward" sdp_combining_options = [ "Use sender's codec order" ] sdp_generation_options = [ ] send_180_with_sdp = false use_isup_oli_format = false use_non_ambiguous_from_tag = false use_reason_header = true use_strict_routing = false user_to_user_encoding = "Escaped text" ``` **Parameters (json)** ``` { "call_transfer_options" : { "call_transfer_mode" : "Relay", "call_transfer_timeout" : "1 minute", "terminate_transferor_immediately" : false }, "ivr_record" : { "vad_enabled" : false, "vad_noise_floor_level" : "-30" }, "lnp_options" : { "incoming_lnp_mode" : "Terminate LNP", "outgoing_lnp_mode" : "No LNP insertion" }, "mlpp_options" : { "look_ahead_for_busy" : "LFB allowed", "network_identity" : 0, "outgoing_mode" : "No MLPP insertion", "precedence_level" : "PL flash override", "service_domain" : 0 }, "name" : "@[profile_name]", "tdm_line" : { "subject_to_electric_hybrid_echo" : true }, "tones_and_call_progress_options" : { "busy_tone_max_duration" : "30 seconds", "default_digit_duration" : 100, "default_interval_between_digits" : 60, "early_media_relay_and_ring_tone_generation" : { "connect_full_duplex_during_early_media" : false, "delay_before_connecting_early_media" : "0 millisecond", "incoming_calls_early_media_mode" : "Forward from outgoing to incoming call", "outgoing_calls_early_media_mode" : "Automatic early media detection", "ring_tone_starting_state" : "Call Alerted" }, "generate_busy_tone" : false, "tone_definition_profile" : "USA-Canada" }, "custom_cause_maps" : { }, "tdm" : { "ss7" : { "default_backward_call_indicator" : "0x5404", "default_backward_call_indicator_enforce_mask" : "0x0000", "default_forward_call_indicator" : "0x2001", "default_forward_call_indicator_enforce_mask" : "0x0000", "dont_forward_early_acm" : false, "force_backward_call_indicator_in_anm" : false, "forward_application_transport_ie" : false, "forward_call_cpg_hold_retrieval" : true, "forward_call_indicator_international" : false, "forward_call_suspend_resume" : true, "hop_counter_ie_handling" : "Decrement and forward", "isup_release_location" : "Private network LU", "relay_release_location_from_other_leg" : false, "send_charge_number_ie_in_iam" : false }, "ss7_or_isdn" : { "always_send_alerting" : false, "cnam_collection_timeout" : "1 second", "cnam_using_alternate_methods" : false, "colr" : false, "information_transfer_capability" : "Relay", "network_specific_facilities_ie" : "", "send_connected_number_ie" : false, "send_display_ie" : false, "support_2_calling_number_ie" : false } }, "voip" : { "fax_modem_relay" : { "detection_mode" : "Standard", "enable_early_fax_modem_tone_detection" : false, "enable_fax_modem_relay" : false, "expected_cng_tones" : 1, "fax_modem_passthrough_parameters" : { "codec" : "PCMU", "detection_type" : "NONE", "force_v152_vbd" : false, "jitter_buffer_depth" : 40, "packet_duration" : "20ms", "support_v152_vbd" : false, "use_nse" : false }, "fax_modem_tones_detection_duration" : "30 seconds", "modem_vs_fax_distinction_timeout" : "0 millisecond", "relay_mode" : "T.38", "switch_to_fax_relay_upon_cng_tone" : true, "switch_to_passthrough_upon_bell_ans" : true, "t38_parameters" : { "fill_bit_removal" : false, "max_bitrate" : "14400", "redundancy_count" : 0, "transmission_level_minus_dbm" : 10, "use_v34" : false } }, "rtp_and_audio" : { "clear_channel_packet_duration" : "20ms", "codec_g726_aal2_format" : false, "drop_call_thresholds_no_rx_packets" : "0 second", "echo_cancellation" : { "echo_cancellation_enabled" : true, "enable_coefficient_update" : true, "enable_dc_removal_filter" : true, "gain_power_level" : "0", "non_linear_processor_tune_option" : "Normal" }, "enable_mos_calculation" : false, "jitter_buffer" : { "initial_depth" : 20, "max_depth" : 200, "min_depth" : 20, "smooth_deletion" : true }, "packet_network" : { "packet_loss_concealment" : true, "type_of_service" : 0 }, "rtcp" : { "rtcp_enabled" : false, "sdes_cname" : "", "transmission_interval" : "5 seconds", "use_xrtcp" : false }, "tdm_volume_control" : { "rx_gain_level" : 0, "tx_gain_level" : 0 }, "vad_noise_floor_level" : "-45" }, "sdp" : { "force_fax_tones_as_telephony_event" : false, "profile_sdp_description" : "m=audio 0 RTP/AVP 0 8 101\r\na=rtpmap:101 telephone-event/8000" }, "sip" : { "custom_sip_bye_headers" : "P-RTP-Stat: PS=@{Stat:Rtp:Tx:IPPackets}, OS=@{Stat:Rtp:Tx:IPBytes}, PR=@{Stat:Rtp:Rx:IPPackets}, OR=@{Stat:Rtp:Rx:IPBytes}, PL=@{Stat:Rtp:Rx:Error:LostPackets}, JI=@{Stat:Rtcp:Jitter}, LA=@{Stat:Rtcp:RoundTripDelay}, DU=@{CallDuration}", "custom_sip_bye_headers_enabled" : false, "detect_180_with_sdp_as_early_media" : true, "dont_forward_183_progress" : false, "dtmf_relay_scheme" : [ "Relay DTMF according to RFC2833", "Relay DTMF using SIP INFO messages", "Relay DTMF in band" ], "enable_sip_custom_headers" : false, "forward_sip_hold_type" : "SS7 Remote Hold/Retrieval", "forward_ss7_cpg_hold_retrieval" : true, "forward_ss7_suspend_resume" : true, "max_forwards_handling" : "Decrement and forward", "sdp_combining_options" : [ "Use sender's codec order" ], "sdp_generation_options" : [ ], "send_180_with_sdp" : false, "use_isup_oli_format" : false, "use_non_ambiguous_from_tag" : false, "use_reason_header" : true, "use_strict_routing" : false, "user_to_user_encoding" : "Escaped text" } } } ``` --- # Agent Instructions This documentation is published with GitBook. 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