I had the chance recently to interview Lane Patterson, Director of Research and Development of Equinix. Equinix is a global provider of network-neutral data centers and Internet exchange services for global enterprises, content companies, and network service providers. The company offers co-location, traffic exchange, peering, and outsourced IT infrastructure services.
Equinix Internet Business Exchange (IBX) centers serve as core hubs for critical IP networks and Internet operations worldwide. With direct access to more than 200 networks, including all of the top global Tier 1 networks, Equinix customers can directly access the providers that serve over 90 percent of the world’s Internet networks and users.
Last October, Equinix announced a partnership with Neustar, whereby they would jointly develop a new generation of services to enhance the interconnection of networks providing advanced services under Session Initiation Protocol (SIP).
I asked Patterson about that relationship, about SIP, and about VoIP Peering in general.
GG: What is the nature of the relationship between Equinix and Neustar?
LP: Equinix and NeuStar have entered into a partnership agreement, whereby Equinix will leverage its exchange and peering services at layers 1–3, and NeuStar will connect with SIP/ENUM services at layers 4–7, in order to provide a comprehensive infrastructure for inter-provider VoIP and SIP interconnection. Equinix is well-recognized as a global authority on peering and inter-provider routing, and NeuStar has expertise in SIP/VoIP, ENUM, e911, PSTN numbering, number portability, and call routing. Both Equinix and Neustar are committed to carrier and provider neutrality, and to developing a long-term infrastructure for the industry. The goal is to provide scalable and interoperable infrastructure allowing next-gen services to work seamlessly across networks.
GG: In your opinion, how important is SIP to the future of communications applications?
LP: SIP is extremely important and quite flexible. Because it is easily extended for VoIP, gaming, video, chat, and other services, it will create a unified and scalable signaling infrastructure for a variety of real-time communications, just as HTTP provided a unified protocol for the exchange of hypertext and other content. SIP supports both one-to-one and multiparty communications. SIP hides the private identity of end users, but provides an easy public way of reaching people using a simple “sip://email@example.com” address that can hide multiple devices and communications capabilities behind it. SIP provides automatic negotiation of capabilities between endpoints, so that the most preferred settings, such as voice or video quality, can be negotiated between callers. SIP has extensions for security and identity, to solve caller-ID spoofing. SIP also adapts well from simple peer-to-peer communications to more controlled carrier environments, where you may have to traverse several proxies and border elements.
GG: How does SIP interoperate with ENUM?
LP: Quite easily. ENUM is based on DNS, and is used to simply translate a TN (Telephone Number) into a SIP Address such as sip:firstname.lastname@example.org, which gives the IP address of the caller’s SIP proxy. So it acts as an IP-enabled phone book. ENUM just handles the lookup for the caller. Once it knows the IP endpoint of the callee, SIP takes over and actually negotiates the end-to-end session, including all the capabilities such as audio/video codec and security settings between callers, and the tracking of the beginning and end of the call.
GG: What are some of the more exciting applications you are seeing in early deployments or in early trials?
LP: An important early step is the successful use of ENUM to automate IP-to-IP routing of calls so calls no longer have to be handed off to a PSTN switch. I’m also excited about some proposed extensions of ENUM to allow it to return SS7-type information for calls that still must go through the PSTN. During the transition, this will be the majority of calls, but ENUM can gradually replace many of the roles of more costly SS7 infrastructure. Of course, the first application of ENUM that’s already in use is to enable users across multiple wireless providers to exchange pictures or rich media between their phones. And SIP-Identity promises to make sure SIP communication does not get filled with SPIT (SPam for Internet Telephony), like our e-mail system has. It can also help run interesting services like age verification that can drive purchasing from SIP-enabled devices. And finally, NeuStar understands e911 for VoIP better than anyone.
GG: How much of an impact will VoIP Peering have on the PSTN in the short term?
LP: In the short term, it will be very gradual. However, if MSO’s get organized, they have the potential to cut hundreds of millions of dollars from their settlement costs by routing calls to each other over IP — even walled-garden IP. And it gives them a great infrastructure to launch features such as video calling that can provide a feature hook to continue to lure folks away from their old-fashioned POTS lines. What remains to be seen on the wireless side is if they will try to wait for IMS, or are willing to move forward with SIP peering. And native SIP communications (e.g., calls to sip:email@example.com, and not to TNs) will probably start emerging with the potential to erode PSTN minutes up to about 20 percent. Other elements, such as Google federating Google Talk with other trusted SIP providers, may develop enough push for this at the right scale. It is important to realize that SIP-IX was built with both early-stage and late-stage PSTN-to-VoIP transition issues in mind and with both open Internet and walled-garden architectures considered.
GG: What are your thoughts on IMS as a roadmap for next generation networking?LP: In short, it will be a long road for IMS. There is great concern about the complexity involved, and there will have to be proper integration of multiple IMS “building blocks” into integrated platforms. The good thing about IMS is the discussion being created, and the care being taken to discuss things like authentication and security, QoS and measurement, customer-network and network-network interfaces, etc. However, there is much that can be done with SIP and ENUM, without presuming IMS.