Microsoft Lync Server 2010 : Benefits for Lync Server Users & Enterprise Voice Benefits

Overview of Unified Communications

Since the first time a call was placed to a phone that did not answer, users of communications devices needed unified communications (UC). However, ask 1,000 IT professionals what UC means, and you’ll likely get close to that number of answers. This is due to that fact that unlike Voice over IP (VoIP), where there is a tangible description of what a technology is or does, UC is s bit more difficult to qualify. Is it collaboration? Is it the capability to see someone’s presence? Is it instant messaging? Is it all of these in a single client? The answer is yes... and no. Without realizing it, as we attempt to collaborate on a more granular and contextual level, we have been unifying our communications slowly and steadily for years.

The truth is that UC more closely defines how humans interact in person. For example, how did you communicate with someone who was having a conversation on a mobile phone? Without thinking about it, you updated his presence to busy in a call. If it wasn’t important, you would probably just wait. However, if you really needed to communicate with someone, you would most likely make eye contact, and, if he signaled to you that he could accept communication from you, you would either use a gesture or speak to him.

This is nearly the same way you communicate when using a UC solution. Utilizing tools such as instant messaging, presence, voice, video, and screen sharing, you are able to interact with others in near real-time, using a familiar interface to provide the same clues and info you get when you interact with someone face to face.

Software-Powered Communication

As computer-processing power has dramatically increased (compare even a low-end workstation of today to the high-end workstations of less than a decade ago), the communications industry has realized that software-powered communication servers allow for dramatic changes in the way both enterprises and consumers interact with one another.

No matter how you define UC, the desire to reduce the latency in user-to-user communication should be a primary goal of any UC strategy. For example, how many times have you been involved in an email thread that stretched out over days or weeks due to time zones or some other reason that could have been solved with a quick, real-time audio conference call?

Enabling users to communicate in the method that best suits their needs at any particular moment, while relaying their willingness and availability to communicate, goes a long way towards reducing the human latency inherent in attempts at collaboration and communications today.

Brief History of UC

Before Voice over IP (VoIP), voice calls were sent over a dedicated network. Each call passed through a dedicated circuit and was switched from one point to the other, hence the term circuit-switched. Although this guaranteed a quality connection, it required dedicated processing power and physical connectivity. For example, the wire that went from your home telephone to the central office (CO) connected you to a physical port on the CO telephone switch. The processor of the CO switch had to constantly monitor each port to determine whether a particular phone (port) made a request to dial a number or access a feature, such as call forwarding.

With a telephone connected to a dedicated network, either the public switched telephone network (PSTN) or an enterprise class private branch exchange (PBX) network, it was difficult for outside influences to affect the quality of a connected call. Although having this separate network held numerous advantages, most notably quality and reliability, individual PBX or CO switches used proprietary protocols limiting interoperability and feature expansion. It also meant, for example, that if you wanted to access your PBX voicemail box from your email client, you were subject to the whim of the PBX voicemail vendor’s decision as to what you could and couldn’t do and what standards were supported.

Using LANs and Packet-Switched Networks

As more and more communications began using LANs and packet-switched networks (the Internet is just a huge packet-switched network), the voice networks were forced to open up and connect to other networks. Unified messaging was probably the first mainstream attempt at UC. Accessing voicemail from your email client and unifying your inbox gave users the potential of true UC. In fact, some traditional phone vendors still consider unified voice messaging the equivalent to UC. Of course, anyone who has shared a desktop with a single click, made a call without dialing a phone number, or created a conference using only the mouse certainly knows that is not the case.

The capability to leverage a database of phone numbers to make calls using the phone was also an early attempt at UC. Anyone who attempted to deploy this type of integration, even as recently as a decade ago, knows that it’s not for the faint of heart and was generally implemented only in narrow cases, such as when a huge database of contacts were dialed by large calling centers. The average enterprise had neither the expertise nor the time and money to implement such a system.

VoIP Becomes Mainstream

When VoIP finally became mainstream, again, the promise of truly UC was presented to the enterprise community. In theory, now that the voice packets were riding the same network as the data packets, how difficult could it be to unify them? A lot harder than it looked.

Although VoIP brought the capability to easily perform day-to-day administrative tasks such as moves, adds, and changes, little was done to unify the communications. Users’ identities were still synched from, and stored outside of, the VoIP PBX, voicemail systems still use proprietary interfaces, and now the quality of the voice call was subject to influences outside of the PBX administrator’s hands. It seemed that, aside from adding complexity to the building of a communications system, VoIP didn’t add that much value overall.

As a new technology, most of the effort in deploying VoIP was put into the actual engineering and the proper deployment of the technology, not in the leveraging of the endless possibilities that existed. In addition, VoIP was initially positioned as a replacement end state for the traditional TDM infrastructure. Enterprises that saw cost savings over dedicated point-to-point (T1) links saw value in VoIP-compatible PBXs, but just replacing the line cord that went into the desktop phone with an Ethernet patch cord didn’t alter the user experience much.

Users still had to remember phone numbers, dial a multitude of phone numbers to reach someone, leave and retrieve voicemail messages using the handset, check multiple voicemail inboxes, and so on. Communications were unified simply because they were using a VoIP-based communications system.

To truly unify communications, begin with a central repository of user attributes at the core of your strategy. This repository should be easily updated, secure, and extensible so that as new features are created, the required attributes can be easily added. If an enterprise has deployed a Windows server infrastructure, it already has a repository in place: Active Directory.

Unlike other solutions, Microsoft’s UC architecture directly uses Active Directory and does not rely on a separate data feed for synchronization. Unlike previous versions, Lync Server now utilizes a Central Management Store (CMS) for all settings and configuration details. This store is replicated to all servers so that servers are now survivable.

Benefits for Lync Server Users

UC solution begins with the end-user experience. Lync Server’s newly designed Communicator client provides a concise, seamless, and logical view to enable users easy access to all communications modalities.

Contacts

Lync Server provides many new, yet familiar, ways to interact, learn about, and communicate with colleagues. The clear view of many data streams enables the user to choose the proper modality to communicate with another user.

Users can save time when locating resources because they can search for others using keywords as well as names. Even with incomplete information, users can locate and communicate with others.

Lync Server also leverages the concept of social networks. Live contact cards, photos, and spoken names enable users to recognize and discover more about the people in their social network that matter to them most.

Users can save time and be more granular when searching, thanks to SharePoint skill search with address book service web queries (ABS-WQ). By simply placing a mouse over a contact, the hover card provides a consistent view of vital user data across all Office products, including Lync Server, enabling users to be more productive and save time by not switching applications as often.

Users that are part of a large enterprise might be overwhelmed by team-level or corporatewide changes by having users’ photos and their spoken name populating the OCS contact list. In this way, users can become familiar with their evolving social network. Users can become better corporate citizens by learning how a new colleague’s name is pronounced prior to meeting or speaking with him or her. You can now quickly see updates from all your contacts in a single concise view, called the Activity Feed.

Contact management is simpler thanks to the unified contact store. Lync Server now utilizes Exchange 2010 for its contact list, so users save time by not having to manage contacts in both Lync Server and Exchange. When the Outlook Social connector is deployed, users can search across their entire social network, such as Facebook from within Communicator.

Users now have easy access to the history of their communication with a particular contact, enabling them to easily determine the context of a conversation and eliminate the need to catch up on a conversation, for example, when usually just a simple IM can answer a question. Similarly, when starting new conversations, a user can easily provide context to a session to further streamline communications.

Managing Communications

Although there are many ways to initiate a call to a contact, users that are transitioning to Lync Server from traditional PBXs will benefit from having an easily accessible dialpad. In the previous version of OCS, the dialpad existed but was not easy to find.

Lync Server users migrating from simple instant messaging and presence on previous versions of OCS to Enterprise Voice on Lync Server will benefit from being able to conduct communications using any modality from a familiar, consistent interface.

When coupled with exchange unified messaging, users can now have a simple-to-view visual representation of each voicemail message. Lync Server users save time by easily managing voicemails within Communicator.

Panoramic Mode

Lync Server clients can leverage the panoramic video of roundtable devices, allowing for a more comfortable face-to-face video experience. This emulates a telepresence environment that integrates well with commodity desktop hardware.

Activity Feed

Users of common current social networks (Twitter, LinkedIn, Facebook, and so on) will immediately recognize and be comfortable with the new activity feed in the Lync Server Communicator client. With a simple glance, you can receive updates (notes) and pictures from those in your social network.

Privacy and Presence Enhancements

Executive users benefit most from the new privacy enhancements in Lync Server. By adding enhanced privacy to a pool, users added to a contact list appear as offline until granted permission by the added contact to see their presence updates. This is valuable, for example, to create ethical walls between departments or divisions. Even if this setting is applied to a pool, users can opt out, enabling all others to see their presence.

Audio and Video to MSN PIC Contacts

Although public instant messaging communication (PIC) has always been a benefit of OCS, Lync Server takes the PIC story a bit further by enabling one-to-one audio and video exclusively to PIC contacts that are homed to the MSN service. This change enables corporate users with a strong MSN presence outside of work to reduce the need to run a separate client on their corporate workstation, yet maintain a robust communications experience.

Enterprise Voice Benefits

Perhaps some of the most tangible, new, and exciting benefits of Lync Server are those related to the Enterprise Voice set of features. With the new release, Lync Server competes with the voice features provided by traditional PBXs. In fact, at VoiceCon 2010, Lync Server won the Voice RFP competition competing against the major PBX manufacturers.

Mediation Server Role Collocation

In prior versions of OCS, the Mediation Server was a dedicated role and required a one-one relationship between the server and the gateway. OCS configuration enabled only a single, next-hop configuration from the Mediation Server to the media gateway (PBX, PSTN, and so on). Although certain gateway manufacturers were able to load-balance calls from the gateway to OCS, OCS was limited to only the single next hop. In Lync Server, the mediation role now runs on the Front End Server as a service. This concept of mediation server collocation provides tangible benefits from a topology, administrative, and user perspective.

With Lync Server, each Front End Server can have its own mediation service, enabling pools to route to gateways instead of the mediation servers. This enables multiple mediation servers to route to the same gateway or multiple gateways to route to a single mediation service.

This capability provides tremendous flexibility to design engineers and enterprises with a large number of PBX/PSTN trunks at a single site or many smaller sites. In previous versions of OCS, these scenarios required a mediation server at each location. In addition to a tangible reduction in servers, this topology change provides greater resiliency, more flexible routing choices, and more options for media flow.

Media Bypass

One of original roles of the mediation server was to transcode between RealTime audio (RTAudio) and G.711 to integrate with standards-based media gateways and PBXs. With Lync Server, calls can be sent using G.711 directly to a supported gateway or PBX. Although low bandwidth signaling (SIP) still traverses the mediation service role, higher bandwidth media (RTP) flows directly from a Lync Server endpoint to the GW/PBX, bypassing the Mediation Server role.

This change provides several benefits, including

• Removes a potential single point of failure that a mediation server introduced
  
  
• Reduces the overall server footprint of OCS
  
  
• Reduces the number of hops a media stream takes
  
  

In addition, in scenarios where a branch appliance is deployed, calls from PBX users at a branch to Lync Server users at the same branch, media now remains at the branch. Prior to Lync Server, an extra mediation server at the branch was required to enable similar call flow.

Optional Dedicated A/V Conferencing Role

In scenarios that require heavy conferencing resources, or MCUs, the A/V Conferencing role can be split off from the Front End Server role. Multiple A/V servers can be placed in a pool and this A/V pool can be designated as the conferencing resource for many other pools. This topology offers a distinct advantage enabling conference-centric enterprises the capability to provide a highly available conferencing resource to the users, but also keeping this resource-intensive application isolated from the day-to-day IM presence and telephony services. Additionally, this enables an enterprise to virtualize basic telephony services while providing physical hardware for A/V services.

Site Survivability

For Lync Server to better compete with other enterprise-grade telephony platforms, resiliency and survivability needed to be addressed. New, additional options for Lync Server topology, along with the introduction of new hardware and server roles, coupled with the support of new DNS options, provide Lync Server architects the ability to craft deployments that are highly available and able to survive failures at various points in the enterprise. This enables Lync Server to continue to provide vital telephony services to Lync Server users.

Survivable Branch Appliance

With the registrar role moved to the Front End Servers and possessing its own SQL express database, pools now have reduced requirements on the back-end SQL database. A survivable branch appliance (SBA) can be set up for branch users as their primary registrar with the pool as their backup registrar.

Lync Server branch users still get their user services from the Front End pool, usually located in a central datacenter. However, in the event of a pool failure, because the branch appliance is aware of the branch user registrations, users at the branch will experience only a loss of user services and still be able to access the PSTN because routing is running on the SBA. Unlike some traditional PBX branch scenarios, Lync Server users benefit from this topology change by not having to re-register to the SBA during a failure.

Supporting DNS Load Balancing

By supporting DNS load balancing (DNS-LB), enterprises that deploy Lync Server can benefit greatly thanks to simplified hardware load-balancing (HLB) configurations. In enterprise HA deployments, HLB are still required for certain traffic, notably HTTP and HTTPS. However, because these are the protocols that are commonly run through load-balanced configurations, their deployment is simpler than in previous versions when SIP traffic also passed through HLBs.

With Lync Server, SBAs are now managed from the CMS database, which provides tremendous savings in the deployment and management of remote locations. Help desks and ISVs can prestage a branch appliance prior to shipping to a remote site. Once onsite, a technician can complete installation. This ease of deployment can be repeated for an unlimited number of sites, greatly reducing the workload of domain and enterprise administrators.

Another topology benefit is a new role, known as a branch office server that can support approximately 1000 users. The new role enables enterprises the flexibility to standardize their deployments across many branches of varying sizes, without sacrificing reliability, providing highly available PSTN connectivity.

In OCS 2007 R2, a common topology was to have dedicated pools at regional datacenters. With this new backup registrar capability, these same deployments can provide an available telephony solution by simply designating an alternative pool from another datacenter as the backup registrar. This feature is known as data center resiliency and provides a limited set of features, including PSTN access, to users whose primary datacenter is unavailable.

When datacenters are connected through low latency (<15ms rtd) WAN links, a single pool can be spread across multiple datacenters. In this configuration, an enterprise provides the entire robust set of Lync Server features out of either datacenter. This configuration is known as metropolitan data center resiliency.

Call Admission Control and DiffServ

Although RTAudio is a flexible payload codec, many larger enterprises believe that Lync Server should support call admission control, or CAC, as well. Already a fixture in many VoIP communications servers, call admission control is now configurable in Lync Server. With Lync Server, network managers can control the amount of bandwidth voice and video calls consume on a given link. By configuring the bandwidth policy service to control a specific site, calls can be rejected or rerouted to the PSTN when sufficient bandwidth is not available to complete the call. This ensures quality audio or video sessions. Enterprises can garner tremendous benefit from planning their CAC strategy prior to deployment.

Lync Server users benefit from its capability to leverage the concept of differential services code points (Diffserv—or DSCP) for audio and video traffic. By separating port ranges for audio and video, Lync Server enables network administrators to provide different per-hop behaviors (for example, EF or expedited forwarding) for these streams. This enables latency sensitive traffic to route ahead of web or other non-real-time traffic. Windows 7 and Vista desktops can leverage Windows-based QoS. This enables them to be provisioned to apply DSCP markings to packets based exclusively on application and port ranges.

By combining CAC, DSCP, and Windows-based QoS policies, network administrators can rely on Lync Server to adhere to the policies they create and deploy on their network to enable all packets to arrive as required and ensure a quality user experience.

E911

Primarily developed for North America, enhanced 911 (E911) allows for additional information to be presented to the public service answering point (PSAP) that enables emergency personnel to obtain details about the specific location of an emergency call. These additional attributes are a building number, mailstop, cubicle number, or any other specific attribute that can save precious seconds in an emergency situation.

Because VoIP is mobile, simply relying on a telephone number is not suitable for IP communications. The new location information service (LIS) role in Lync Server enables network identifiers such as switch ports, subnets, and wireless BSSID information to be matched up with location information and transmitted to the PSAP when setting up a 911 call. In addition to regulatory compliance benefits, e911 allows for a safer telephony environment. With Lync Server’s E911 service, end users trust that calls made to a 911 service will provide the vital details to emergency personnel.

Location can be set through the policy or manually. Visual indication of the current location is presented directly in the Lync Server client. E911 can also be configured to enable other onsite users to be automatically conferenced into an emergency call, enabling corporate first responders to be aware of 911 calls as they happen, which coordinates with police, fire, and other emergency services as they arrive.

Malicious Call Trace

When a Lync Server user receives a call that she deems is harassing or threatening, she can flag it in the call database. By alerting system administrators of this fact, they can quickly determine the source of the call and trace it back to its origin for evaluation by security personnel.

Caller ID Controls

Lync Server allows for a user’s caller ID to be modified dynamically based on the destination of the call—internal or external. This enables an enterprise to maintain full reverse name lookup to the corporate directory for internal calls, but provide a uniform departmental or location number to be presented when making external calls. This is used in certain situations such as outbound call centers, support desks, or any other situation where it is necessary to block caller ID digits to external parties. This can be set at a user level or by policy.

Anonymous Agents

Lync Server response group agents can be placed in anonymous groups. This feature enables help desk personnel to participate in a response group without providing a name and number to internal users.

Prior to Lync Server, users calling a response group saw the agent they were connected to in their Communicator client and frequently then bypassed the response group on subsequent calls, defeating the purpose of the group by failing to leverage the available pool of agents. Lync Server response groups in anonymous mode are suitable for use in scenarios where the agent’s number needs to be kept private.

On-Net and Off-Net Voice Routing

For an enterprise to benefit from a large geographically dispersed voice network with many PSTN egress points, the capability to route calls through these points is crucial. However, when the points are located in different cities or countries, each point can require different dialing formats, prefixes, or other access codes. This can add tremendous complexity to a corporate dialing plan. Fortunately, Lync Server provides central alternative routes and number-formatting changes to manipulate the dialed number prior to routing to a PBX or the PSTN.

Media Gateway Certification

Beginning with OCS 2007, Microsoft developed the open interoperability program (OIP) for PBX and gateway vendors to enable enterprises to determine whether a particular piece of hardware or software version is certified to work with OCS. Beginning with Lync Server, audio quality and performance testing is included in OIP certification. This enables systems engineers to design a solution that will perform properly for all communication modalities.