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SIP and VoIPState of the Nation
Internet2 Sip.EDU WorkshopMinneapolis, Minnesota
Feb 2007
Walt Magnussen, Ph.D
Texas A&M University
Director TAMU ITEC
Agenda
• Standards
• Platforms
• Services
Standards
• The following slides are provided by Dr. Henning Schulzrinne, Columbia University
Evolution of VoIP
“amazing – thephone rings”
“does it docall transfer?”
“how can I make itstop ringing?”
1996-2000 2000-2003 2004-
catching upwith the digital PBX
long-distance calling,ca. 1930 going beyond
the black phone
SIP is PBX/Centrex readycall waiting/multiple calls
RFC 3261
hold RFC 3264
transfer RFC 3515/Replaces
conference RFC 3261/callee caps
message waiting message summary package
call forward RFC 3261
call park RFC 3515/Replaces
call pickup Replaces
do not disturb RFC 3261
call coverage RFC 3261
from Rohan Mahy’s VON Fall 2003 talk
simultaneous ringing
RFC 3261
basic shared lines dialog/reg. package
barge-in Join
“Take” Replaces
Shared-line “privacy”
dialog package
divert to admin RFC 3261
intercom URI convention
auto attendant RFC 3261/2833
attendant console dialog package
night service RFC 3261
centr
ex-s
tyle
featu
res
boss/admin features
attendant features
IETF VoIP efforts
SIP(protocol)
SIPPING(usage, requirements)
ECRIT(emergency calling)
AVT(RTP, SRTP, media)
ENUM(E.164 translation)
IPTEL(tel URL)
SIMPLE(presence)
GEOPRIV(geo + privacy)
usesmay use
uses
provides
usually
used with
IETF RAI area
MMUSIC(SDP, RTSP, ICE)
XCON(conf. control)
SPEERMINT(peering)
uses
SPEECHSC(speech services)
SIGTRAN(signaling transport)
uses
A constellation of SIP RFCs
Resource mgt. (3312)Reliable prov. (3262)INFO (2976)UPDATE (3311)Reason (3326)SIP (3261)
DNS for SIP (3263)Events (3265)REFER (3515)
DHCP (3361)DHCPv6 (3319)
Digest AKA (3310)Privacy (3323)P-Asserted (3325)Agreement (3329)Media auth. (3313)AES (3853)
Non-adjacent (3327)Symmetric resp. (3581)Service route (3608)User agent caps (3840)Caller prefs (3841)
ISUP (3204)sipfrag (3240)
Security & privacy
Configuration
Core
Mostly PSTN
Content types
Request routing
SIP, SIPPING & SIMPLE –00 drafts
includes draft-ietf-*-00 and draft-personal-*-00
0
10
20
30
40
50
60
70
80
1999 2000 2001 2002 2003 2004 2005 2006
SIP
SIPPING
SIMPLE
RFC publication
0
2
4
6
8
10
12
14
2001 2002 2003 2004 2005 2006
SIP
SIPPING
SIMPLE
IETF WG: SIP
• ~ 44 SIP-related RFCs published
• Activities:– hitchhiker’s guide– infrastructure:
• GRUUs (random identifiers)
• URI lists• XCAP configuration• SIP MIB
– services:• rejecting anonymous
requests• consent framework• location conveyance• session policy
– security:
• end-to-middle security
• certificates
• SAML
• sips clarification
– NAT:
• connection re-use
• SIP outbound
see http://tools.ietf.org/wg/sip’/
IETF WG: SIPPING
• 31 RFCs published• Policy
– media policy– SBC functions
• Services– service examples– call transfer– configuration framework– spam and spit– text-over-IP– transcoding
• Testing and operations– IPv6 transition– race condition examples– IPv6 torture tests– SIP offer-answer examples– overload requirements
Conclusion• Core standards for media and signaling are finished
– can build PBX-equivalent devices and services on a large scale• see BT, FiOS, Vonage
• Lots of decent server implementations (various vendors; SER, openSER, Asterisk)– but lack of good soft clients for major OS platforms
• Ossification of Internet requires application complexity– kludge around NATs, lack of QoS– lack of credential infrastructure
• Intersection with policy and business models– NGN, 3G: maintain voice as high-value monopoly service
• Not a protocol engineering effort, systems engineering
Platforms
• Enterprise VoIP
• Carrier Platforms
• Open Source
Enterprise Platforms
• Cisco Call Manager– Still supporting Skinny with robust SIP support
• Trunk side (4.0 and greater)• Line Side (5.0 and greater)
• Nortel CS-1000 BCM and MCS 5100– Unistim for full feature functionality– Trunk side SIP only at this time (4.0 and greater)
• Avaya– Sip support for line and trunk
• 3COM– Built on SIP
Carrier Platforms
• Exclusively SIP
• Major vendor support– Broadsoft (Verizon and many TISP providers)– Cedar Point– Sonus
Open Source
• Being implemented in many startup solutions (i.e. DetD) – SIP only as well– ASTERISK– IPTel SER– Open SER– Sip Foundry SIPX
• Campus wide solutions– Penn State– UNC– Sam Houston State (Texas)
Services
• Trunking
• Peering
• Hosted Centrex
• E-911
• Peer to Peer
Trunking
• IP trunk access to PSTN avialable from several service providers today (Level3, Paetec etc.)– Inbound and outbound LD– Local access under LNP– 800 Services– Directory Assistance
• Advantages– Allows converged access– Lower cost– Eliminates Local PRI costs– Allows easy diversity (when coupled with LCR)
Peering
• Commonly used by VoIP service providers– Uses ENUM for scalability– Various service providers
• Voice Peering Forum http://www.thevpf.com/ • Verisign NRD service
– Hardware solutions can augment service• Nextone does MOS calculations and dynamic
rerouting when necessary.
Hosted Centrex
• Talked about a lot by Industry
• Currently offered by Verizon HIPC
• Under evaluation at TAMU (more to follow)
E-911
• Location of devices not required on most campuses (but highly recommended)
• Fixed locations supported by:– Telemanagement systems (i.e. Pinnacle)– ILEC services (Verizon and AT&T)– Hardware solutions (i.e. Cisco)
• TAMU solution– Lock down fixed telephones per port– ID mobile devices (softphones) in database
• More elequent solutions to appear under NG911
Peer to Peer
• Not supported by most campuses but rampant (i.e. Skype)– Blocked by many international service
providers– UC Santa Barbra approach is to block
http://www.oit.ucsb.edu/connect/skype.asp
Questions ?
• Contact info:– Walt Magnussen, Ph.D.– ITEC Director– [email protected]– 979-845-5588