VoIP scenario s within NRN networks and possible roles of the NRN Erik Dobbelsteijn for TERENA TF-VVC Plaats en datum
Introduction The word VoIP both covers a lot of technologies and a lot of possible usage scenarios which lead to confusion This document gives an overview of VoIP scenarios that NRNs can encounter and decribes possible roles of the NRN for each scenario: 0) Traditional Campus infrastructure 2) VoIP on the Campus 3) VoIP between Campus locations 4) Trunk termination 5) Outsourced PBX 6) VoIP-VoIP routing by the NRN
0) Traditional Campus infrastructure Campus Rest of Telephony world PBX
1) VoIP on the campus Instead of a traditional (TDM) PBX, a VoIP-based ipbx dispatches all telefphone traffic Telephones are connected to the ipbx through the institutional LAN Calls destined outside the campus are carried over ISDN30
1) VoIP on the campus Campus Rest of Telephony world ipbx LAN
1) VoIP on the campus Role: None Optional: consulting Case for the institution: Using existing LAN (but: sometimes separate LAN necessary) Advanced features Integration with institutional services (CRM etc) Easy to work from home (VPN necessary)
2 VoIP between locations Instead of sending calls between different locations of one institution ISDN, this can be done over VoIP over NRN.
2a VoIP between locations If the institution has PBXs Location 1 PBX Location 2 NRN Internal calls GW Othe r cal ls Rest of Telephony world GW alls c r e Oth PBX
2b VoIP between locations If the institution has a ipbx NRN Location 1 Internal calls ipbx LAN Location 2 LAN Othe r cal ls Rest of Telephony world
2b VoIP between locations Role: None Optional: consulting Impact Availability of the network should be high Network should be collision free (so have low latency and jitter) Case 2a for institution: Investment: 2x gateway Maintenance cost (low) Savings: inter-location call costs Case 2b for institution: Savings: inter-location call costs
3a) VoIP trunk termination Instead of sending calls from an institution to an outside destination (PSTN) over ISDN, this can be done over VoIP. NRN transports VoIP traffic to a commercial carrier that takes care ( terminates ) it. Two ways to connect the campus: A) ipbx: delivers VoIP to the WAN B) PBX: a gateway converts TDM calls coming from the PABX to VoIP, which delivers VoIP to the WAN
3a) VoIP trunk termination Campus Carrier ipbx Call Control Rest of Telephony world NRN GW Campus GW PBX
3a) VoIP trunk termination Role IP carrier Impact Availability of the network should be high Network should be collision free (so have low latency and jitter)
3b) VoIP trunk termination by NRN Instead of sending calls from an institution to an outside destination over ISDN, this can be done over VoIP. NRN transports VoIP traffic to a commercial carrier that takes care ( terminates ) it. Two ways to connect the campus: A) (i)pabx delivers VoIP to the WAN B) a gateway converts TDM calls coming from the PABX to VoIP, which delivers VoIP to the WAN
3b) VoIP trunk termination NRN Campus ipbx Call Control Rest of Telephony world GW Campus GW PBX
3b) VoIP trunk termination Role IP carrier Voice carrier Impact Availability of the network should be high Network should be collision free (so have low latency and jitter) NRN might be considered a Voice carrier by regulator, meaning that NRN should at least support Number portability Lawful intercept NRN should find cheap carriers to terminate traffic or even participate in wholesale minute market NRN should bill its costumers depending on a tariff model (per minute/flat fee)
4a) VoIP as outsourced service An institution does not have an (i)pbx of its own, but rents phones including a telephone number for its employees and/or students from Service Provider Institution receives a monthly bill for rent and calls Service Provider provides call control, institutional number plan, advanced features, termination, end-user support and billing
4a) VoIP as outsourced service Campus Service Provider ipbx Rest of Telephony world WAN (NRN) GW LAN
4a) VoIP as outsourced service Role IP carrier Impact Availability of the network should be high Network should be collision free (so have low latency and jitter)
4b) VoIP as outsourced service by NRN An institution does not have an (i)pbx of its own, but rents phones including a telephone number for its employees and/or students from NRN Institution receives a monthly bill for rent and calls NRN provides call control, institutional number plan, advanced features, termination, end-user support and billing
4b) VoIP as outsourced service by NRN NRN Call Control Rest of Telephony world GW Campus LAN
4b) VoIP as outsourced service by NRN Role IP carrier Voice carrier Impact Availability of the network should be high Network should be collision free (so have low latency and jitter) NRN is concidered a Voice carrier by regulator, meaning that NRN should at least support Number portability Lawful intercept NRN should find cheap carriers to terminate traffic or even participate in wholesale minute market NRN should bill its costumers depending on a tariff model (per minute/flat fee) NRN should have end-user support desk Billing
5) VoIP-VoIP routing by NRN Inter-institutional VoIP-VoIP calls can be routed by NRN independent of VoIP-to-PSTN traffic flows PBX: gateway at campus necessary ipbx: H.323: through GDS (already in place) SIP: under development at NRN
5) VoIP-VoIP routing by NRN Campus ipbx NRN Campus Call Control Campus ipbx GW Option 0, 2 or 3 Rest of Telephony world PBX
5) VoIP-VoIP routing by NRN Role IP carrier Call Control/Trusted Third Party Impact Inter-instutional traffic is small Bussiness case to place gateways at campuses that don t have VoIP has proved negative previously Availability of the network should be high Network should be collision free (so have low latency and jitter) NRN should have wholesale support desk Billing
Other roles 4 Extend functionality (to the end user): IM/Presence Authentication infrastructure to authenticate end-users Authorisation infrastructure to control sessions VoIP retail/end user services like Pilmo.nl Optibel.nl Not considered: closed VoIP systems like: Skype VoIPster
Combinations of roles Connecting a Campus to the outside world can be done in different ways: Type of PABX PABX ipabx ISDN30 v v VoIP v* v Termination * = gateway necessary
Legenda and Abbreviations GW Gateway, TDM-to-VoIP gateway ipbxip-based PBX ( VoIP PBX ) PBX Public Branch exchange PSTN Public Switched Telephone Network TDM Time Division Multiplexing, traditional telephony VoIPVoice over IP, internet telefphony IP connection TDM connection IP trunk TDM Trunk IP phone TDM phone