LanScape Centrex Proxy Server™ - User's Reference
LanScape Centrex Proxy Server®
Tile Page
Part Number
Software License Agreement
Getting Started
The LanScape Centrex Proxy Server®
General Description
Proxy Server Configuration
Performing Configuration
Configuration Dialogs
Basic Settings
Network Configuration
Call Processing Timeouts
Local Directory
Call Routing
Global iNet® Accounts
Media Proxy Support
Event Logging
Wan IP/NAT Detection
Custom Plug In
SIP Logging
Backing up and restoring configuration information
Backing up the proxy configuration
Restoring the proxy configuration
Running Multiple Instances
Running more than one proxy on the same machine
Running the proxy server as a service
Running the proxy server as a service
Proxy Plug-in API
Plug-in API General Description
Deployment Scenarios
Deploying in the global IP address space
Deploying in your private IP address space
Help File Version
Help File Version






“Allowing  you to do what you do best, communicate.” ™




Thank you for purchasing LanScape VOIP application software. We are extremely pleased to have an opportunity to offer this feature rich, network based telephony technology to you. Our single greatest hope is that you discover this incredible technology and harness it for your own benefit.


This edition of LanScape’s Centrex Proxy Server® is designed for the Microsoft Windows family of operating systems and the universally renowned Global iNet® Telephony Network. The LanScape Centrex Proxy Server® is an enhanced SIP compliant proxy server. It is simple to use and can be deployed as easily as a standard email server. In addition, the LanScape Centrex Proxy Server® can be teamed up with the LanScape VOIP Media Proxy Server® to offer a full, secure session and media proxying VOIP solution. When properly configured, the Centrex Proxy Server® and VOIP Media Proxy Server® work together to offer similar capabilities that are only available in expensive 3rd party session border controllers and session boundary controllers. These 3rd party network elements are expensive and usually cost thousand of dollars.


The Centrex Proxy Server® is used to create VOIP call domains that can be addresses statically or by today's leading dynamic DHCP services. In general, the Centrex Proxy Server® acts to connect VOIP call endpoints using the SIP protocol. In addition, the Centrex Proxy Server® also performs complex NAT protocol packet IP address and port "fixups" as would be performed by expensive 3rd party dedicated hardware session border controllers and boundary controllers costing thousands of dollars. When the LanScape Centrex Proxy Server® software is teamed up with the LanScape VOIP Media Proxy®, complete VOIP call processing and full media proxying can be achieved regardless of the media format.


With your new LanScape Centrex Proxy Server®, you instantly have many new and exciting network based voice possibilities at your fingertips. The new telephony capabilities LanScape brings to you are perfectly suited for your consumer or business oriented needs and will allow you to obtain the highest degree of use from your current internet service provider or internal network infrastructure.


In short, we offer you the ability to perform network based telephony that will allow you to communicate with your people of interest. This new capability will transform how you think about network telephony and how you do business.


There are two fundamental ways you can deploy this Centrex Proxy Server® SIP proxy:


As a telephony participant of the world wide Global iNet® Telephony network.

As part of your very own private VOIP network phone system (your own VOIP domain).




Telephony participant of the Global iNet® Telephony Network


For users that are deploying the Centrex Proxy Server® in addition to LanScape Global iNet® enabled soft phones, be prepared for a very pleasant surprise. Once you configure your Centrex Proxy Server® to log into specific Global iNet® user accounts, your "registered" VOIP users will be able to initiate and receive network based phone calls worldwide using Global iNet® directory services. The Global iNet® system will keep track of missed phone calls and alert users appropriately as calls are logged. Users can employ the capability of Global iNet® to search for any other user or company in the database system. You can think of the Global iNet® system as a world wide directory lookup service that augments your VOIP telephony capabilities. In other words, the "world wide" phone book.



Deploy your own private phone system


You now have the ability to completely create your own  private Voice over IP (VOIP) telephone network within your personal, private, business or educational organization. Creating your VOIP phone system is easy when the LanScape Centrex Proxy Server® is deployed in conjunction with the LanScape VOIP Media Proxy®, optional LanScape's Voicemail server and optional LanScape Global iNet® soft phone software.


Because of the hostile nature of today's IP4 network and the inherent issues facing the SIP protocol due to network address and port translation, the Centrex Proxy Server® software is generally deployed with one or more LanScape VOIP Media Proxy® servers to make up a complete, secure and functional session and media proxying solution. No other software or dedicated border controllers are required.



A few examples...


Example 1: A small VOIP deployment would consist of a single Centrex Proxy Server® and a single VOIP Media Proxy® server to achieve full session and media proxying capabilities. This small configuration uses a single registrar database to manage users and can be deployed in the global IP address space or behind your outermost private network firewall or router. Your VOIP domain can be assigned a static IP and use DNS for domain name resolution or it can use a dynamic IP address assigned by your service provider and use dynamic DHCP services to resolve your VOIP domain name. Pure simplicity. Even though we described this scenario as a "small VOIP deployment", this deployment model can handle thousands of registered users. The maximum number of concurrent media streams that can be handled concurrently are a function of the media proxy server hardware and maximum available network bandwidth. As you require more media proxying capabilities, you simply add another media proxy server to your deployment. Media proxying is fully scalable.


Example 2: A larger VOIP deployment may consist of one or more Centrex Proxy Servers and one or more VOIP Media Proxy servers. The number of servers you deploy depends on your total session call handling load and the maximum number of concurrent VOIP calls (media streams) you want to proxy. All of your deployed Centrex Proxy Servers can be configured to use a shared common registrar database to manage users. All of the VOIP Media Proxy servers you deploy can also be load shared by all of your Centrex Proxy Servers. In this way, a VOIP domain can be configured that can support thousands and thousands of users and as many simultaneous calls and media sessions as required. Scalability has been designed into the Centrex Proxy Server® and VOIP Media Proxy® server software so any combination of session and media proxies is possible.



In addition...


The Centrex Proxy Server® (and optional VOIP Media Proxy® server) can be deployed in the global IP address space or immediately behind your domain's outermost router or firewall. Some deployment rules must be followed to ensure VOIP best practices however, the deployment rules that must be followed are simple and will be easily managed even by freshmen network administrators.


The interesting aspect associated with creating your own VOIP network, is that you have many options regarding your overall deployment. For simple VOIP deployments, you generally deploy a single Centrex Proxy Server® (for handling session initiation via the SIP protocol) and one VOIP Media Proxy® (for proxying voice media). That's it. You can select whatever soft or hard IP SIP compliant phones you desire. Optional capabilities would be VOIP voicemail (LanScape Voicemail Server) or PSTN gateway connectivity (LanScape PSTN Gateway® Server, Cisco gateway products or the open source Asterisk PBX).

Your VOIP network can be totally private within your organization or can be accessible using a well known DNS domain name. Note: You do not need a static IP for your domain name - dynamic DNS services work just as well.

If you deploy your LanScape VOIP solution as directed, you will be able to initiate and receive calls from any other SIP compliant VOIP system or SIP compliant domain worldwide.





Additional Information you may find interesting:


Voice over IP is an exciting and new technology that is easy to apply and simple to use. However, let us assure you, the task of developing an implementation all of the underlying software technology in addition to creating robust telephony applications around these technologies is laden with idiosyncrasies and traps.


We here at LanScape have performed research and testing of many of the most current VOIP telephony technologies available. We have determined what has been successful and what has not. We have also performed studies that show what IP telephony functions and features are demanded the most and which features are very rarely used.


Like all new software technologies, the use and application of VOIP by end users and by the developers of product oriented companies can be a risky business. All of you reading this preface who are involved in the sales, marketing and development of software for your companies know how difficult “getting it right” is. Most often, developing a supporting technology needed by your end product or service ends up detracting you from the real task at hand. We have been there, we know.


In the ideal world, you would be able to design your product or service around off the shelf technologies in addition to your own internal software intellectual property. For most companies, the goal would be to minimize the time of the development and test cycles so as to deploy the end product/solution/service to the market as fast as possible. In most cases, this fast deployment allows quick feedback from the field relative to how well your team has met requirements. In this scenario, your company has the added advantage of realizing a revenue stream faster and minimizing risks associated with unfamiliar technologies. As time progresses over the life cycle of your product and/or service, your development team has the ability to “design out” any or all procured hardware and/or software technologies thus allowing you to achieve a pure, “wholly owned” product based completely on your hardware and software solutions.


That’s the ideal world. In reality, what most companies do is to identify technologies that work for them and their customers and stick with it. Typically, once a hardware or software solution is integrated into the final version of a product or service model, it often remains until the product/service has reached the end of its life cycle and is retired.


This is where LanScape’s VOIP technologies enters the picture. You have the immediate ability to plunge into the VOIP product sector with much reduced risk and diminished time requirements. You have the ability to enhance your products and end user experience using VOIP right now.  You can view the entire packetized voice telephony “function block” as a turnkey solution. If this is the first deployment of VOIP by your company, you will gain immediate positive results with a fraction of the effort. We cannot stress this enough. You will be able to remain true to your original task and remain focused on your end results.


Internet/packetized voice capability is a very interesting technology. VOIP can assist you in propelling your products into application spaces you might not have previously thought possible. As mentioned earlier, we here at LanScape have conducted studies over the past few years. To us it is clear and evident. Its not a question of “if” VOIP will be widely adopted, it is a matter of “when”. The “when” clause in most cases has already morphed into “now".


For individuals new to voice over IP technology, the question most often asked is: “What minimum network infrastructure must I have to deploy VOIP?”. The answer is: “What you have right now”.


There are the VOIP “purists”, who claim you must have special quality of service monitoring and control in addition to a changeover of current equipment to support voice traffic. For most cases this is not true and is not a factor. Most residential and corporate networks are sitting there most of the time doing nothing. However, if you are in a network environment where you are already hitting the limit of your network resources, then yes, the network will have to be “built out” to support additional data carrying capacity.


Typical VOIP applications can be hosted on 10 or 100 Mbps Ethernet, 802.11 wireless LAN/access points, broadband, DSL, or other modest network connections having a minimum full duplex average throughput of 64kbps. If you have never experienced low latency VOIP telephony using 802.11 wireless Ethernet, then you are in for a pleasant surprise. The LanScape VOIP Media Engine™ was designed to directly address the needs of the above mentioned network infrastructures, especially the wireless network topologies.


The application of VOIP are indeed only limited to the extent of your imagination. If you are completely new to VOIP or telephony in general, sit back, read and absorb. Also, be prepared to receive the sense of accomplishment you will soon be experiencing as your new product or service allows your customers to do what they do best, communicate.





LanScape, Inc