E-SBCs: Beyond Security

Ask the SIP Trunk Expert

E-SBCs: Beyond Security

By Steven Johnson, President, Ingate Systems, Inc.  |  December 10, 2012

This article originally appeared in the Dec. 2012 issue of INTERNET TELEPHONY

Enterprise session border controllers play a number of key roles in the enterprise network. Security is one very important function of the E-SBC, and just as a CIO would not tolerate connecting any server directly to the public Internet, or even to a private MPLS network, neither should they allow the IP telephony system to be configured with a publicly routable IP address. The E-SBC also provides the means to give the IP PBX (News - Alert) a private IP address, and traverse the NAT with SIP signaling and related media. And because of the nature of the product, it is the place to stop denial of service or theft of service attacks before they wreak havoc on the network and the business. Today’s E-SBCs all support the tools necessary to manage, control and secure the IP PBX away from these risks.

But the best E-SBCs do more than secure the perimeter of the network when introducing SIP, SIP trunking and unified communications. The E-SBC also enables SIP trunking, interoperability, routing, diagnostics, troubleshooting, encryption, authentication, disaster recovery and much more. The E-SBC has evolved to be an important element in the implantation of any SIP-based communication and to perform a variety of necessary functions.

We’re going to be taking a deeper dive into some of these important functions to help end users get the most for their E-SBC investment. First up: troubleshooting.

Placed at the enterprise edge, E-SBCs serve as a demarcation point between the delivery network and the customer. Many service providers want a clear hand-off point between their networks and the end customers. Using an E-SBC as the demarcation point, the ITSP can see both the LAN and the WAN side of the customers’ networks.  This is a powerful troubleshooting tool, as it aids in determining where messaging and/or media is reaching. The E-SBC can also show detailed logging information, including debug messages which can assist in troubleshooting issues throughout the enterprise network. In this way the E-SBC can gather the statistics necessary to monitor service delivery to maintain quality of service.

In other cases the end user installs the E-SBC and uses it to determine whether the service provider is delivering satisfactory service based on the service level agreement that is in place. This may include generating call quality statistics, often called MOS scores, to demonstrate whether the service is as advertised. The E-SBC may also be used to isolate the issue between the WAN and the LAN, thus helping to pinpoint the source of any issues that may develop.

Clearly, the position of the E-SBC in the network makes it the perfect choice for identifying, isolating and resolving quality issues for voice over IP or unified communications implementations.

Looking ahead, we’ll talk about several other E-SBC functions:

  • Interoperability;
  • enabling Microsoft (News - Alert) Office 365 and Lync implementations;
  • authentication, encryption;
  • quality of service;
  • disaster recovery; and
  • redundancy

If there are other topics you’d like to see covered in this column please let me know ([email protected])

Steven Johnson (News - Alert) is president of Ingate Systems (www.ingate.com).

Edited by Brooke Neuman