Voice Direction follows strategic planning for network innovations

Foreward: When someone says "VoIP" I always hear "network" because it's the network that allows VoIP to function beyond a stream of IP packets between adjacent devices. How well it functions depends upon the design specifications of the IP network. But before we explore further let us go back a bit to the other network used for voice services. The public telephone network, or PSTN, is a carrier-based network and it uses E.164 numbering as end user addresses. The PSTN started life as a geographically aligned system of area codes and local exchanges and evolved to provide a central directory service used to call other subscribers whose number they might not know by heart -- or to find local services in the yellow pages. Relatively recently the use of E.164 numbering by cellular providers and the rules which allow number portability have given us new insights into how a large network might best be used for mobile voice, video, chat or other real-time services.

I will describe where where we are now in terms of voice service choices for end users and will attempt to provide some details on the strategic implications of each service. Today and in the past, business analog service is availble to those users who choose not to upgrade to VoIP or cannot do so because of infrastructure limitations. Verizon Centrex provides business analog dial tone services for the UP residence halls and provides emergency as well as elevator phones. At some point business analog could be contracted through a alternate vendor if costs rise to a point where alternates are sought; but for the foreseeable future TNS will continue to offer a business analog service.

By 2001 a group at U.P. had begun testing with the second generation of VoIP hardware. A large part of the testing was related to developing network specifications in order to ensure a reliable and supportable VoIP system to be overlaid onto the University Park Campus portion of the network. As a result of the testing as well as the ongoing administrative overhead of proving and procuring a scalable VoIP system was put in place. The VoIP system today has almost 13,000 IP phones and we are driving towards the migration of a portion of the 5,000 or so business analog phones to VoIP. The University Park VoIP system connects to the outside world primarily via the PSTN, although a secured link from a field trial SIP system allows inbound calls to reach the VoIP system. Strategically this UP VoIP system is expected to remain in place for the foreseeable future, beyond five years -- due to the limited capabilities of crystal ball I use (smile).  TNS' focus is to upgrade the system regularly in order to preserve supportability (by Cisco, the vendor) and to continue with network changes towards continuous improvement to the availability of UP VoIP.

The field trial of the SIP system is over and Soft Phone service will begin this September. We're very close and we need to complete the access and authentication portion, the "front end" of this service, before it can be released. Soft Phone is similar to Skye in that it enables identity based communications. What all does it do -- Soft Phone provides the feature set based upon the client you choose. If the client you choose supports voice, video and chat, then these will function with the first and all subsequent phases of Soft Phone. The first phase of this new service is straightforward and simple - it will enable authenticated and authorized users the ability to connect PSU UserID to UserID from any network to any network. The next phases include an improvement in functionality to enable inbound calling from Soft Phone to translate a PSU UserID to a phone number and to ring the telephone at the campus end. Soft Phone will leverage the central directory service already exists within our IP network in order to enable translations between PSU UserIDs and the telephone number listed in PSU LDAP. The next phases of Soft Phone (over the next 1 to 3 years) will see additional features and move system features up to a level where inbound calls from the public telephone network are delivered to soft phone clients.

The Soft Phone service is a standards based service, describing that end users can select their own SIP client and that the core equipment of Soft Phone will use open source code products such as Asterisk or SER. By using a standards based service TNS will achieve voice and video interoperability between unlike systems. A caveat needs to mentioned as some vendors have extended the standards and this will no doubt cause some features to fail, but overall the standards ensures that common functions will be successfully connected through network links where bandwidth and delay are within specification. Since Penn State’s IB is within these specifications, the structure of Soft Phone will enable inter-campus communications with relatively little effort and with modest cost for the core equipment . Since each campus location can decide whether or not to participate in Soft Phone; where participation requires dollars be spent to construct an IB connection and to put a security device in place, a team from TNS  is already working with one campus to ensure the Soft Phone model is established via a field trial.  

The end of the campus PBX upgrade project saw seventeen PBXs upgraded, including the two here at (UP) PSU Hospitality Services.  The upgrade marked the new age of IP-PBX systems at all PSU campuses. As a partner to this change, TNS has worked closely with SOS and with end users to come up with an agreeable method to secure these sensitive systems while maintaining access for authorized functions. The PBXs are now protected by firewalls and the network routing is limited to PBX administrator access via the VPN.