Setup of ENUMbased services: The Generic Gateway Reference Implementation

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Setup of ENUM-based servicesThe Generic Gateway
Reference Implementation

• Michael Haberler
• Internet Foundation Austria
• 11/2004

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outline

• about us
• problem the basic techniques
• call flows for voice SMS
• description of reference implementation
• application example virtual number resale
• lessons learned
• survey of available components/suggestions for
  trying things out

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us our role

• Internet Foundation Austria
• Goal fostering the Internet development in
  Austria
• subsidiaries
• nic.at GmbH handling .at TLD 400.000 domains,
  35 people
• enum.at GmbH Tier1 registry for 43 e164.arpa
  until 2007
• concluded operations contract for 43 with
  Austrian regulator in 8/2004
• developed ENUM registry from scratch
• startup of full service scheduled for Dec 9, 2004
• ipCom GmbH (in startup) will provide
• Tier2 portal
• ITSP supply services PSTN/IP gateway, SMS/IM
• goal is to develop the market by transferring RD
  to services
• 5 people, 2 years ENUM trial, platform
  development operations experience

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Internet PSTN call legs
sipanne_at_isp.at 43 780 1234
43 1 5261670
Media Gateway
ENUM DNS
31 20 12345
sipbert_at_isp.de 43 780 5678
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The generic gateway trick

• The problem is getting services out of PSTN onto
  IP other direction is usually easy. Use ENUM to
  figure out where the endpoint is.
• Igredients
• Take any service addressed by E.164 numbers.
  (voice, SMS, IM, presence, Video..) for which you
  can provide a gateway.
• Get a number range for IP endpoints.
• Get relevant telcos to handover service to
  gateway (ISDN, SS7, SMPP, 3G-324, whatever).
• Create compatible IP endpoints with URIs, assign
  E.164 numbers ENUM domains
• ENUM lookup drives gateway, service delivery.
• Result soft user-configured gateway service.

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Generic Gatway exampleVoice
PSTN
Internet
6.5.4.3.2.1.0.8.7.3.4.e164.arpa
4. sipmah_at_nic.at43.at
2. 43 780.
5. INVITE sipmah_at_nic.at43.at
Telekom PSTN Switch
nic.at43.at
PSTN-IP Gateway
1. 43 780 123456
6. INVITE sipmah_at_nic.at43.at
sipmah_at_nic.at43.at
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Generic Gateway exampleSMS delivery
PSTN
Internet
6.5.4.3.2.1.0.8.7.3.4.e164.arpa
4. sipmah_at_nic.at43.at
2. SMS via SMPP
5. MESSAGE sipmah_at_nic.at43.at
MO SMS Center
nic.at43.at
at43 SMPPServer
6. MESSAGE sipmah_at_nic.at43.at
1. SMS an 43 780 123456
sipmah_at_nic.at43.at
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the enum.at generic gateway reference
implementation (voice)

• covers PSTN-gtIP
• does SIP, H.323 and ifaxmailto based on ENUM
  (public or private)
• functionality based on service set agreed in 43
  intercarrier working group
• uses ISDN PRI (now)
• harmless investment 2 Cisco AS5XX0s and 2
  servers will do - fully redundant
• will scale, work and get service out
• things it doesnt do
• codecs Cisco doesnt like (yet)
• easy handling of several number ranges
• announcement text free of charge (TBD)

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Generic Gateway Architecture
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Hardware/Software Cisco GW

• at least one PRA interface and one Fast Ethernet
  interface
• at least one voice feature card (vfc) module
  installed (DSPs for VoIP).
• Cisco IOS version
• IOS (tm) 5300 Software (C5300-JS-M), Version
  12.2(13)T3, RELEASE SOFTWARE (fc2)
• Fax onramp application
• fax_on_vfc_onramp_ap

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Hardware/Software Helper PC

• Standard x86 compatible server hardware
• Operating system Debian woody 3.0r2 Linux
• Radiator (or any other radius server which
  supports execution of perl scripts and database
  accounting)
• Perl (included in Debian distribution)
• Perl enum.pm module from http//jprs.co.jp/enum/so
  ftware/ENUM.pm
• postgresql database (for storing accounting data,
  included in Debian)
• exim SMTP server (for delivery of fax emails,
  included in Debian)
• procmail (for email handling, included in Debian)
• dnsproxy from http//www.wolfermann.org/dnsproxy.h
  tml with modifications to rewrite old-style
  NAPTRs.
• tftpd server (included in Debian)

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application examplevirtual number wholesale

• virtual presence in a location is an issue (not
  just for offshore tax-shelters )
• theres a wholesale market starting
• basically number -gt SIP URI mapping
• around 1/month wholesale
• straightforward to implement withnumber range,
  generic gateway andENUM registrar

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virtual number resale 43 case
ENUM registrar
ITSP offering virtual numbers
wholesale contract provisioning protocol
delegation
subscription VoIP service
operating contract
ENUM
lookup
generic gateway operated by telco
subscriber
43 780 ENUM-driven number range
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virtual number resale benefits

• telco one gateway, any service, any business
  case
• registrar potentially popular service,
  especially in countries with large expatriate
  communities
• user can use number on-net too besides being
  reachable from PSTN
• this is what is under construction in Austria
  (available Q1/2005)

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what we would do different if we were grown up

• have an SS7/ISUP translator driving the MG with
  SIGTRAN
• look into VoIP/GSM roaming (see BridgePort
  MVNO/SIP gateway)
• to do list
• SMS/smssip/smsmailto gateway (just about ready)
• generalized enum rewriting (so much about
  standards compliant hardware)
• generalized stack activation

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this is an open source product

• watch www.enum.at or drop me an email

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what we are investigating/playing with

• were building a generic gateway for SMS for at43
  and then 43 780
• smssip - map onto SIP MESSAGE, fallback to
  smsmailto
• mobile operators converge on the Wireless
  Village IM presence protocol. This is an URI,
  and thus an ENUM opportunity. Look at
  www.webmessenger.com.
• an ENUMservice for Jabber (IDA)
• The way Push-to-Talk is implemented is asking for
  Internet extension.
• were looking into a UMTS Video-gt SIP H.263
  gateway service with ENUM mapping.

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recommended links for hands-on experience

• Basic SIP-based VoIP, Instant Messenging,
  Presence
• get an account at www.fwdnet.org
• try the Windows Eyebeam SIP client www.xten.com
• try instant messenging with SIP and the Windows
  Messenger
• note this is not the same as Microsoft Messenger!
• Linux try Linux kphone http//www.wirlab.net/kpho
  ne/
• good information source on VoIP
  http//www.voip-info.org
• Ready for your own SIP server?
• try SIP Express Router www.iptel.org
• try the Asterisk IP PBX www.asterisk.org
• both are ENUM enabled out-of-the-box
• try the ENUM resolver at http//jprs.co.jp/enum/so
  ftware/software.html
• to read up on ENUM, try http//enum.nic.at