The convergence of three phenomena – businesses’ migration toward IP-based communications, increasing numbers
of states requiring businesses to adopt so-called “enhanced 911” services and the proliferation of “hosted” services – is raising the profile of equipment that controls real-time session network traffic, an industry insider told TMCnet in an interview.
“Session border controllers” – or “SBCs,” as they’re known – control traffic at the packet, call control and signaling layers as that traffic crosses between networks or network segments. They’re critical to VoIP – or Internet-based phone calling networks – because they help audio packets that are sent across a network cross so-called “network address translation” – or “NAT” – devices, as well as firewall boundaries.
Consider the critical role that the technology plays in E911, which leverages location-based technology to pinpoint the whereabouts of 911 callers, often saving critical emergency response time.
Officials with Burlington, Mass.-based Acme Packet
– a company that makes SBCs and multiservice security gateways, among other technologies – say they’re seeing greater numbers of businesses, including those with multi-site campuses – turning toward SBCs for E911 solutions, particularly as SIP trunking emerges as an industry standard.
Generally speaking, SIP trunking is a service offered by Internet telephony service providers so that businesses can adopt VoIP using their Internet connection. That way, they can communicate with others who rely on the PSTN, since the enterprise IP-PBX (News
) is connected to the service provider’s PSTN gateways over the Internet.
To a casual reader, that’s a lot of industry jargon. Essentially what it means is this: SIP trunking makes it easier for businesses to migrate toward IP-based audio communications. Naturally, when that happens in a workplace, it’s critical for businesses to ensure that their workers are safe and can rely on their phone system to place 911 calls effectively.
According to Michael Leo, Acme Packet’s (News
) director of enterprise and contact center solutions marketing, SBCs play a critical role in hosted E911 solutions because they ensure secure access to hosted services.
One recent example that Leo cites in his interview with TMCnet (printed in full below) is while working with one Chicago-based E911 solutions provider, RedSky Technologies
The company’s “E911 Anywhere” hosted solution, which is designed to meet business needs as well as regulatory requirements, leverages Acme Packet SBC to ensure that an E911 system functions well.
Our full exchange follows.TMCnet: It seems to us that – given Acme Packet’s central goal of delivering high quality interactive voice, video and multimedia communications across IP network borders – the use of the company’s session border controllers in enhanced 911 deployments is a natural fit. We’re seeing more and more states – most recently Massachusetts – pass legislation requiring organizations to provide E911 solutions to ensure their workers are safe, requiring E911 solutions. What kind of uptick, if any, has Acme Packet seen in this segment in recent months/years?
Michael Leo: As more and more enterprises are moving to VoIP and replacing their old PBXs with new unified communication solutions, they are discovering that emergency services like 9-1-1 need to be addressed differently from what they were doing before.
The flexibility that IP telephony offers, like desktop mobility, now requires an application like RedSky’s (News
) E911 Anywhere solution in order to meet both business and legislative requirements. And the ability to offer this service as a secure hosted solution is where an Acme Packet SBC comes into play. We are definitely seeing more distributed enterprises looking at SIP trunking to access hosted services, and SBCs offer not only SIP trunking termination but secure access to hosted services like those offered by RedSky.
TMCnet: Talk to us, specifically, about how Acme Packet’s SBCs are supporting RedSky’s E911 Anywhere Hosted application. Clearly, security and reliability are essential in E911. How do your company’s SBCs protect an application and/or servers from Internet threats? How does the Net-Net 3800, in particular, meet that need?
ML: Unlike traditional firewalls that are designed to handle data traffic, Acme Packet SBCs are purpose-build to protect and secure IP communications. This is done using a back-to-back user agent which terminates all VoIP traffic, inspects it, and then can do a number of things to the packet – like convert the packet from H.323 to SIP, manipulate the SIP header to properly route it, or remove the packet if there’s something wrong with it - before passing it along. And since one of the areas where business are leveraging VoIP is supporting remote workers that use the Internet to access corporate voice services, a SBC can be use to secure these “untrusted” endpoints at that border. It also provides for DoS (Denial-of-Service) attack protection.
TMCnet: We hear from IT insiders that SIP trunking is emerging as an IP communications industry standard, and we know that RedSky’s E911 Anywhere Hosted service can use SIP signaling to send a 911 call over a private network in cases where a client has an IP-PBX. Talk to us about how those calls are processed by the Acme Packet SBC.
ML: SIP trunking is a hot technology which can deliver not only cost savings to an enterprise but advance hosted services like RedSky’s E911 Anywhere. The Acme Packet SBC performs several services for the RedSky solution. First of all, our Net-Net platforms perform Layer-5 topology hiding. Utilizing a feature called HMR Bridging, header manipulation rules are employed. These rules dictate that messages will have the IP address in the From-URI replaced with that of the SBC. Likewise, the IP address in the To-URI is replaced with that of the RedSky E911 Anywhere Hosted (VPC) SBC. These rules allow RedSky to strip, replace or append PAI headers as needed.
Also, the SBC’s feature-set allows RedSky to employ further redundancy which is critical to this kind of hosted service. In certain scenarios, the VPC may send 4xx or 5xx SIP messages back to the RedSky core, denoting the unavailability of interfaces. The SBC has the ability, using a feature known as a SIP response-map, to translate these SIP messages into a format that the softswitch recognizes. The softswitch can then dial out a PRI to an alternate site where the 9-1-1 call will be answered by a live operator who will then in-turn route the call to the correct PSAP.
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Michael Dinan is a contributing editor for TMCnet, covering news in the IP communications, call center and customer relationship management industries. To read more of Michael's articles, please visit his columnist page.
Edited by Michael Dinan