SBCS Technical Webinars Fax Support in SBCS

1. SBCS Technical WebinarsFax Support in SBCS Marcos Hernandez Technical Marketing Engineer marchern@cisco.com SBSBU January 2009

2. Agenda • Fax Transmission Technologies • Fax Passthrough • Fax Relay • Cisco Fax Relay • T.38 Real Time Fax • Store and Forward (T.37) • - Onramp & Offramp • SBCS Fax Applications • T.38 in a Multisite deployment • T.38 Capable ITSP’s • Fax to Email using CUE • Fax Detection (Single DID for Fax and Voice) • Printing Faxes • Fax Rollover • StoneVoice Integration • Additional Resources

3. Fax Passthrough

4. PSTN PSTN PSTN PSTN IP Cloud packet loss, jitter,delay Fax Passthrough Long Distance ($$$) Modem/Fax Call Path via Modem Passthrough TDM Switch TDM Switch Fax Fax Traditional Modem/Fax Call Path Modulated Data OGW TGW Fax Fax PSTN

5. FaxPassthrough Details • Transport of modem/fax signals through a packet network using PCM encoded packets. • A Fax tone triggers passthrough operation. After that, upspeed to g711, jitter buffers are locked and echo cancellation disabled • Fax tones are exchanged inband. • Fax Passthrough is a special case of Modem Passthrough. VBD (Voice Band Data) is Modem Passthrough.

6. Fax Passthrough Global Setting Configuration ! voice service voip fax protocol pass-through g711ulaw ! This will cause all voip dial-peers to have fax protocol unless ‘no fax protocol’ is configured on the dial-peer

7. T.38 Fax Relay

8. Cisco Fax Relay • Cisco FR and T.38 are conceptually identical. Cisco FR was implemented prior to the T.38 standard (similar to what happened with Cisco PoE), and that as a general rule, you would use T.38 since it is standardized.   • Only reason for Cisco FR is compatibility with old hardware/software. • The rest of this presentation covers only T.38 concepts and services.

9. T.38 Real-time Fax (Fax relay) solution Overview T.38 Fax Machine Voice GW Voice GW IP network H.323/SIP/MGCP ITU-T T.38 Fax Relay ITU-T T.30 Group 3 fax ITU-T T.30 Group 3 fax

10. T.38 Encapsulation Group 3 FAX Group 3 FAX Voice GW Voice GW IP Cloud FXS FXS T.38 Data Packet Encapsulation (UDP/TCP) T.30 Fax Commands,T.4 Fax Image Transfer V.21 Carrying T.30. V.17/V.27/V.29 Carrying T.4.

11. Real-Time Fax and T.38 • Value • T.38 standard vs. Cisco proprietary fax relay • Cost reduction through use of IP network • Localized T.30 communication better than Fax Passthrough • Extend delay tolerance – T.30 spoofing, extra line padding, data redundancy • Improved delivery - “never busy service” (T.38 can fall back to T.37)

12. T.38 Global Setting Configuration ! voice service voip fax protocol t38 ls-redundancy 0 hs-redundancy 0 ! This will cause all voip dial-peers to have fax protocol unless ‘no fax protocol t38 …’ is configured on the dial-peer

13. T.37 Store and Forward

14. S&F Onramp function Messaging server F IP PSTN • Authenticate sender against AAA • Demodulate fax call and perform ITU-T T.30 fax protocol handling • Encode fax image into TIFF file • Create MIME email message with TIFF attachment • Forward to ESMTP mail (fax) server. • Create call history and AAA accounting records

15. S&F Offramp function Messaging server IP PSTN • Authenticate sender against AAA • Rasterize text portions of e-mail (text->fax) • Decode TIFF-F image into fax pages • ITU-T T.30 fax protocol handling • Modulate fax call • Create call history record

16. Store and forward fax • Value • Integration with standard email • Improved delivery - “never busy service” • Cost reduction though use of IP network • Store-and-forward offers features (broadcasting, customized cover pages, email conversion) • More reliable through storage • Green (saves paper) 

17. SBCS Fax Applications

18. Full Mesh Hub and Spoke Site 1 Hub Site 2 Spoke 1 Spoke 2 Site 3 Site 5 Spoke 3 Spoke 4 Site 4 T.38 In Multisite Deployments • In a multisite Voice deployment, T.38 is recommended as all UC500 sites support it. • Significant bandwidth savings

19. T.38 Capable ITSP’s • Currently, T.38 support is minimal in the ITSP Community • From the CCA 1.9 list of supported providers, only XO and Nuvox support T.38 • Please contact your ITSP to check for T.38 support. T.38 UC500 VoIP PSTN ITSP Gateway Fax Machine

20. Fax to Email using CUE • Fax Caller from the outside calls the SMB fax number. • The fax line is connected to one of the POTS ports on the UC500 (T.37 not supported over VoIP trunks). That means that the UC500 will answer the call. • A script on the UC500 converts the fax message to an image file (.TIFF extension). • The UC500 forwards that message to a CUE voice mailbox designated for this purpose. • Notifications are enabled for the Fax mailbox. • CUE will then send an email to the address specified in the notification settings. • The email will contain the original fax message as a .TIFF attachment. UC500 POTS PSTN Fax Machine Email Server

21. Fax Detection • Fax detection supports the use of a single E.164 number for both voice mail and fax mail by providing the capability to detect through an interactive voice response interface whether an incoming call is voice or fax. • Cisco provides a special script (named app_fax_detect.2.1.2.2.tcl) that will detect a fax tone if the call is a fax call and process it accordingly. If on the contrary, the call is a regular voice call, the UC500 will just route as such. • Some issues: It takes up to 9-10 seconds to detect a fax call. Single DID sounds great, but in should only be used where absolutely necessary – e.g. DIDs are too expensive. • Fax storage in CUE can be used.   PSTN POTS DID UC500 Email Server

22. Printing Faxes • The UC500 can be configured to send faxes that are stored in CUE, to a local fax machine for printing. UC500 (CUE)

23. Fax Rollover • The fax rollover IVR application provides a configured fallback to T.37 store-and-forward fax if a call attempts to use fax relay and fails. An OGW must be configured with fax relay, store-and-forward fax, and also with the fax rollover application. Then, if a fax relay attempt fails, the call is forwarded to an SMTP server by a mail transfer agent (MTA) using T.37-standard protocols for store-and-forward fax.  T.38 1 VoIP PSTN UC500 ITSP Gateway Fax Machine T.37 2 Email Server

24. T.38 Fax Server from StoneVoice • StoneFax can automatically route incoming faxes in TIFF format to each user's mailbox and personal web interface, picking out the right recipient by the Called Line Identifier (DID support) or by the line on which the fax was received. This enables users to check faxes from anywhere in the world using either: A traditional desktop email client (i.e.: Outlook, Lotus Notes...). This is the Fax through email feature A web browser (Internet Explorer, Netscape Navigator...). This is the Fax through web feature • To send a fax, each user can either: Create it as a new message in his/her email client, the Email To Fax featur Upload a document via web through a dedicated web page, the Web To Fax feature Directly print from any application to the StoneFax network printer, the Print To Fax feature • After the fax is sent, the user receives a transmission report in his/her inbox. • More information on: http://www.stonevoice.com/Products/IPFaxServer/tabid/762/Default.aspx

25. Additional Information and Troubleshooting Cisco Fax over IP Application Guide (Geek Alert!) http://www.cisco.com/en/US/partner/docs/ios/12_3/vvf_c/cisco_ios_fax_services_over_ip_application_guide/faxapp.html Cisco IOS Fax Support http://www.cisco.com/en/US/tech/tk652/tk777/tsd_technology_support_protocol_home.html Fax to Email In UC500 App Note https://www.myciscocommunity.com/docs/DOC-1516 For questions: www.cisco.com/go/smallbizsupport

26. Glossary ITSP – Internet Telephony Service Provider CUE – Cisco Unity Express (Voicemail Module in UC500) IOS – Internetwork Operating System (Cisco Device OS) CME – Communications Manager Express CCA – Cisco Configuration Assistant PCM – Pulse Code Modulation DID – Direct Inward Dial MIME – Multipurpose Internet Mail Extensions AAA - Authentication, Authorization and Accounting SMTP – Simple Mail Transport Protocol H.323, SIP and MGCP – VoIP Signaling Protocols ITU – International Telecommunication Union V.XX and T.XX – ITU Recommendations for Fax Transmissions (see backup slides for details) TIFF - Tagged Image File Format OGW/TGW – Originating Gateway/Terminating Gateway

27. Backup Slides

28. Why is Fax Passthrough needed • Marketing Needs: cost savings • End User: by past long distance PSTN • Carrier: Simplify call management: voice , modem, fax can all be treated the same way. • Technical Needs: TDM network is different from packet network modem and fax are designed for TDM networks • designed to operate over synchronous TDM network • optimized to use the full PSTN channel bandwidth • overcome common line impairments seen in the PSTN • Not for packet network (packet loss, jitter, delay, compressed codec, asynchronous gateways)

29. T.38 Standards • T.4 – Defines encoding of printed data (modified Huffman encoding) • T.30 – Handshaking protocol for FAX call setup and transmission • T.38 – Fax Relay over IP Networks • V.17 – High Speed FAX (9600-14400 Bps) • V.21 – Low Speed FAX (300 Bps) • V.27 – High Speed FAX (2400-4800 Bps) • V.29 – High Speed FAX (4800-9600 Bps)

30. T.38 Fax Relay Function F PSTN IP • Authenticate sender against AAA • Demodulate fax call and perform ITU-T T.30 fax protocol handling • Encapsulate T.30 messages into T.38 packets and send out over IP Leg • Encode fax image into T.4 Format • Create call history and AAA accounting records

31. T.38 Fax Relay Function IP PSTN • ITU-T T.30 fax protocol handling • Receive T.30 messages within T.38 packets coming from IP Leg • Decode T.4 image into fax pages • Modulate fax call • Create call history record

32. T.37 S&F Fax solution overview Message routing, storage and transport Cisco On-ramp Gateway Cisco Off-ramp Gateway IP network ON-RAMP OFF-RAMP T.37 SMTP (RFCs 821 & 1651) MIME (RFCs 2405-2409) I-FAX (RFCs 2301-2305) ITU-T T.30 Group 3 fax ITU-T T.30 Group 3 fax