VoIP: Integration with Microsoft Lync

CET303 – Telecommunications

Robert Ian Hawdon, University of Sunderland

bf78gz@student.sunderland.ac.uk

AbstractThis article looks into the different methods of connecting to VoIP and Unified Communication systems, with detailed focus on Microsoft Lync, and how it could be implemented into Sunderland City Council.

Introduction“It will be very difficult to buy anything except IP Telephony in the future” – Alex Hadden-Boyd – Director of marketing Cisco (Paulson,2005)

VoIP (Voice over Internet Protocol) is a technology that allows one to communicate with others over a data network connection using voice.

The ability to utilise fast data connections this way allows for companies and individuals to set up direct links between friends and colleagues without needing to pay expensive phone bills, whilst providing a better quality of service than that over the more traditional methods of telephony.

The problem is, there are many services and methods of implementing a VoIP network. Some would benefit companies better than others.

Sunderland City Council is looking to implement a Unified Communications

network at their sites, which needs to be tailored to work for them.

Unified CommunicationsUnified communications is a term to describe a service that integrates Voice, Video, Data and Mobile services on a network.

(Shangying and Yun, 2010)

Using digital services for communication has numerous advantages over older analogue infrastructures. For example, setting up a VoIP service to replace analogue phone lines will reduce cost to run the system, and improve the quality of calls.

There are various different ways to connect to a VoIP service: IP Phones, Mobile Apps, and Soft Phone client software.

SIPSession Initiation Protocol (SIP) is the protocol VoIP services use to connect between two end points. It’s used as a replacement of the older H323 protocol. SIP is commonly used as it is simpler due to having less components. (Tan and Goh, 2002)

SIP has quickly become a popular alternate method of transferring voice and video in a telephone like service. This is due to the ability of adding many features a standard

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telephone system would simply not be able to achieve.

For example, SIP allows for users to engage in a conference call, allowing members of a team to be able to join in the same conversation without needing to be in the same place, or even the same part of the world. SIP clients are mobile, which means the same account can be used anywhere in the world where there’s an internet connection. This means that no matter where someone is, they will always have the same contact details which will allow them to be easily contacted no matter where they are in the world.

Because Unified Communication solutions are accessible anywhere in the world, they could save a company vast amounts of money, even to the extreme of being able to do away with a physical office all together, and basing the whole company in the cloud. People would be able to work from home, and have business meetings though the voice and video services the UC service provides.

SIP ServersTo connect to an SIP service, there needs to be a server for the client to connect to. There are a few different servers a company could use. Some of these are free and open source, whilst others are proprietary.

An example of a free server is Asterisk, which allows one to create different internet telephony solutions, such as PBX, VoIP gateway. Asterisk also understands many of the various VoIP protocols, works with PSTN (Public Switched Telephone Network) systems meaning the VoIP system can be integrated with an existing analogue phone system.

Asterisk’s other features include the ability to track the usage of user account’s phone habits which could be used for billing purposes. It

can also be managed online using its web services, record calls, convert text to speech and voice recognition. (Digium, Inc., 2010)

More commonly used features in Asterisk are automated answering service, which allows users to select the various departments they want to contact via a menu system, and the ability to link multiple Asterisk servers together.

Over a wide area network (WAN) it would be highly recommended to use a virtual private network (VPN) to ensure that conversations over the system can’t be intercepted. (Iseki,Sato and Kim, 2011)

Because Asterisk is open source, it’s possible to develop new plugins, or modify it to add new features. Automatic Speech Recognition is once such modification that can be done, which would allow a company to save money by allowing the first level of support to be answered by a machine which understands human voice, rather than employing a whole call centres worth of staff. (Goel et al., 2009)

Asterisk is designed to run on Unix-like operating systems including GNU/Linux, Open and FreeBSD and Mac OS X. (Digium, Inc.,2010) This means companies would have to hire someone who’s familiar with one of these systems if they want to implement Asterisk as their phone server, as no Windows version is available.

An example of a proprietary SIP server is Cisco Unified Communication Manager which aims to: boost productivity, allow people to work together in certain applications, increase business innovation, and reduce the complexity of the IT infrastructure. (CiscoSystem Inc., 2009)

Cisco’s solution works virtually identically to how an Asterisk system does, but unlike Asterisk, it comes with dedicated support

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from Cisco. The server will also run on Windows based server solutions.

Sunderland City Council use Avaya to manage their VoIP solution, there are a few disadvantages to the Avaya system, one being the requirement of two separate licences, and that the Voice Mail service can’t be restored should something happen to the system. Avaya is also difficult to update and upgrade, requiring the whole system to be rebooted after changes. This means the whole phone system needs to be taken offline to make changes. (WVoip, n.d.)

ClientsTo connect to an SIP server, a user needs a method of connecting to the service. This can be in the form of a physical IP phone, an application on a smart phone, or an SIP client for computers. (Pierce, 2010)

X-Lite is a popular SIP client for Windows and Mac OS X systems, which allows any computer running these operating systems to act like an IP phone. (CounterPathCorporation, 2011)

X-Lite is no longer available for Linux systems, though at one point there was. Users using Linux would need to use an alternate client. The benefit of SIP is that the majority of clients should work on the same service.

Ekiga, on the other hand, is an open source client which runs on Windows and GNU/Linux. It supports many of the features that are used in X-Lite, and as it’s open source, gets updated with bug fixes regularly.

An historical example of a VoIP client is Microsoft NetMeeting which was first introduced as an add-on for Windows 95(Sullivan, 2003) and was one of the first clients for home systems to allow for live video conversations. NetMeeting also allowed

for users to use a virtual whiteboard, and transfer files to each other. (Reilly, 2000)

VoIP phones are a more traditional way of connecting to an SIP server. Some users feel making calls are much easier and a better experience on a physical phone, due to the way it acts like a regular telephone. Connecting a VoIP phone to a SIP network is a simple process of configuring the phone to know where the SIP server is, and providing the username and password details. It will then function the same way as a softphone client on a computer would.

Microsoft LyncMicrosoft Lync is a unified communications client and server that was made public in January 2011. It was designed to allow workplaces to distribute teams over a large area, and give them the tools to work from there. It is designed to integrate with Microsoft office applications such as Outlook and Word, and brings together the ways people communicate (via Voice, Instant Messaging, Video conferencing, etc.), and put them into one integrated interface.(Microsoft, 2010)

Lync is able to work with Microsoft office to show other users who’s working on the same document. It uses SIP to handle its voice communication. Everything works through Microsoft Lync Server, which can be installed onto a company’s internal server system, and accessed either internally, or over VPNs to get a secure connection.

Benefits of LyncUsing Lync as a company’s Unified Communication solution has benefits which wouldn’t be possible with older solutions. For example, a number of people could be using it in a virtualised business meeting, using its

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voice and video services, whilst sharing files over its system. If the members of the meeting feel they could benefit from the advice of another colleague, they would be able to see if they are available to talk, and invite them into the meeting with ease.

Lync will also integrate with address books (globally) through an Exchange server, which allows for ease of use trying to find a particular colleague you’re trying to get in contact with. This saves time for both the user, who will just want to be able to call someone they want quickly, and the administrator who’d only need to set up a contact list on a central server, rather than providing instructions for everyone to build their own address book.

As Windows is the most popular operating system, it’s most likely a company or organisation, such as Sunderland City Council, will be using it on their systems and the fact that Microsoft office is still the most popular office suite (Montalbano, 2009), means that the majority of Lync users will be running a full suite of Microsoft applications. Because of this, Microsoft have tailored their Lync service to work with these systems.

The Lync client comes free with some of the Microsoft Office suites, which would be a hook to get companies interested in using the technology. By using a soft phone client rather than a physical IP phone, companies can save money, which could be another reason Microsoft is pushing this technology out to clients this way. This is an example of Microsoft’s aggressive marketing strategies.

Microsoft has made Lync mobile clients for all of the major smart phone platforms (iOS, Android, and Windows Phone) which means being able to take business communications anywhere on the move is a realistic benefit.

Integration with current systemsA lot of companies are already using services similar to the ones offered by Microsoft Lync. For example, many companies have their own phone system in place which uses VoIP.

A company might, for example, be using Asterisk, an open source VoIP server, to power their phone services. Asterisk is free, and can be deployed over multiple servers. It is commonly run on Linux servers which, again, keep costs down for a company, as most Linux systems are free. The down side to this setup is that if there’s a problem, there’s no dedicated support, and system administrators are generally on their own.

As Microsoft Lync is proprietary and aimed at businesses, they provide support for this product should it be required. This, and the fact it integrates many separate products into one convenient package, makes it an attractable product for businesses.

But, switching from one system to another isn’t simple, as some systems will refuse to run Lync, and it is incompatible with some VoIP phones. Also, changing the whole system at once is unrealistic, as the phone service would have to be taken offline for an extended amount of time, and the new system will have some bugs that would need to be ironed out.

So, what can be done, as Lync uses SIP, it is possible to set up an SIP trunk to connect a Lync server to an Asterisk server, in the same way you can connect two Asterisk servers. This way, an office, or business, which an already established IP phone service, can start adding a Lync service and be able to call between both systems. (Jacobs, 2010)

The downside to this is that only the voice portion of Microsoft Lync will function for

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those users calling in from the external SIP service which could be a problem when dealing with teams that require access to the same documents.

Alternatives to LyncThere are many alternatives to using Lync, though not as one combined program. As already mentioned, there is the Asterisk VoIP server, which will let the user us any SIP client, SIP smart phone apps, and IP phones, to log in and use the voice service.

In the world of cloud computing, there are many services set up to allow for syncing files between devices and co-workers. Dropbox and Ubuntu One are such examples. Files are automatically synced to the computers the account it’s associated with, as well as being available online.

Problems with LyncMicrosoft Lync has a few down sides which companies should consider before implementing on their system.

Firstly, files larger than 4GB can’t be sent to other users, this could be an issue if the company using the Lync system is often going to be transferring large files between users. An example of a time where large files need to be sent could be when transferring video or audio files between members of a team. Using a public storage system within the company’s network could be one solution to this.

Conversation histories aren’t saved if the Microsoft Exchange Server isn’t installed, which could be an issue if someone wants to look back at a conversation, either for personal, or legal purposes.

Another big drawback of Microsoft Lync is that it’s only supported on Windows and Mac

platforms. This means companies who choose to use Linux based environments, or alternative office suites are unable to benefit from the full advantages Lync offers. Microsoft currently have no plans to release a Lync client, or support Office 365 on Linux (Microsoft Corperation, 2011), meaning if Linux clients are going to be used, other arrangements would need to be made to allow these users to connect to the communications network.

Side note: Microsoft Acquisition of SkypeIn May 2011, Microsoft announced it was to acquire the VoIP technology Skype for $8.5 Billion (USD). They intend to use this acquired technology for a range of their online services including, Xbox, Windows Phone, Outlook, and Lync. (Microsoft Finalizes Acquisition ofSkype for $8.5 Billion., 2011)

Skype uses a different technology over SIP, from codecs, to how users interact with each other. (Sat and Wah, 2006) Skype usernames must be unique globally, whilst each SIP server can have a username that’s present on another server. (TechGenie, 2010) Skype is also a closed network, unlike SIP which is an open network which can be customised for business needs.

Skype’s other disadvantage is it uses the client machine as a server, which means it will use a significantly higher amount of bandwidth than an SIP solution. SIP services work more like a regular telephony system. Because of this, businesses are more likely to choose an SIP network infrastructure for their telephony needs.

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Recommendations for the councilFor Sunderland City Council, it would be well advised to consider integrating Microsoft Lync with the system currently in place. This would allow for a smooth transition to the new system, with minimal downtime. Ideally, part of the old system, Avaya, should either remain in place, or be replaced with an alternate solution, such as Asterisk, to allow clients who can’t benefit from Lync’s services directly (Linux clients, older VoIP phones, etc.) to use the new service. This can be done using an SIP trunk.

As the council is split over multiple sites, it’s also highly recommended to invest in a VPN solution, if there isn’t one already. This should ideally, be in the form of a dedicated connection, or alternatively, part of a converged network with sufficient Quality of Service (QoS) policies in place, to ensure voice and video calls are given highest priority over data network traffic. The VPN will ensure that calls can’t be intercepted when travelling over the internet which could be a security threat.

Implementing Lync into the councilIf Sunderland City Council wishes to invest in Microsoft Lync, they would need to look into Windows servers, if they’re not using them already, to allow for a Lync service to run. If they aren’t running a suitable Windows server, a Windows server licence would need to be purchased, as well as the appropriate hardware, unless they choose to use a virtual server.

A dedicated server would be a more ideal solution, as rouge processes on other virtual servers, or within the same server, wouldn’t be able to affect the VoIP solution.

Using an SIP trunk, the Lync server needs to be integrated with Avaya to provide backward compatibility with the phone service that’s already implemented.

The VPN needs to be tested to make sure it can’t be tapped into from an external connection, which could mean data is at risk.

Finally, it’s imperative that the system is regularly tested to make sure it can make emergency calls should the need arise. Failure to do so could breach health and safety laws in the workplace.

ConclusionMicrosoft Lync has numerous advantages over other systems providing Unified Communications. But this only really the case if it’s implements properly. Poor planning and preparation could cause disaster for the council’s phone network structure and these need to be taken into account before messing around with their phone network.

These advantages are only useful if everyone on the system is using Microsoft’s products, and if some clients rely on other services, such as a Linux system, Lync can suddenly become very limited in what it can achieve. This is down to Microsoft, rather than something from the client’s set up. Whilst the ideas behind Microsoft Lync are very appealing, appropriate research into the companies network needs to be conducted, and any improvements to get a site “Lync Ready” needs to be done before deciding whether or not Lync really is the solution the company is looking for.

Lync has the potential to be the next big thing in Unified Communications, provided some of the shortcomings stated in this article are addressed.

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