Fixing Call Issues in a Mitel 3300 - Lync 2013 Deployment

We recently deployed Lync Server 2013 Enterprise Voice for a customer who at the same time replaced their old Mitel PBX with a newer Mitel 3300. The customer wasn't ready to make a full commitment to Lync for voice traffic, but probably 80% of the customer's users are using Lync exclusively for voice.

The Lync infrastructure was connected to the PSTN via the Mitel 3300 PBX using direct SIP.  While things initially seemed to be fine, we were getting numerous reports of sporadic failed calls throughout each day.

Digging through the monitoring server reports (deploying monitoring server reports should be considered ESSENTIAL for any Lync Enterprise Voice deployment), we could see a clear trend for the call failures: Looking at the Failure Distribution Report, we could see the top failed call reason was Gateway side Media negotiation failed.

Clicking on the sessions number hyperlink brought us to the list of calls that failed due to that cause.  Selecting one shows the session detail report for that call:

At the bottom is the Diagnostic Report.  Clicking the Detail link on the server side finally shows the exact reason for the call failure:

10010; source="LyncFE.contoso.com"; reason="Gateway side Media negotiation failed"; component="MediationServer"; ValidationError="SDP Exchange already failed before SetAnswer: Session c line = 0.0.0.0 or ::, call hold not allowed for initial INVITE offer"; GatewayFqdn="10.1.1.2; trunk=NA-OH-Dayton-Mitel"

I did a search through my normal channels and didn't come up with much.  I saw a few references to clients who set the Lync client audio port range to 3, rather than the recommended 20-40 which caused their particular issue, but we were already using 40 as a client port range.

It seemed as though the issue was coming from the Mitel side.  I tried a few things like setting the trunk's RTCPActiveCalls and RTCPCallsonHold values to FALSE on the Lync side, but that had no effect.

We tried to contact the Mitel partner who put in the Mitel system, but they were of very little help.  I asked if I could poke around the Mitel web console to look for a potential fix. Surprisingly, the client said "Sure".  Having never seen a Mitel before, I thought that things were about to go very wrong, or at least we wouldn't get any closer to a solution.

Since the error was related to SDP, we focussed on the SDP Options tab under SIP Peer Profile on the Mitel.  The most promising option was Avoid Signalling Hold to the Peer.  It was promising because the error message from the Lync monitoring reports mentioned both SDP and hold, so.......we set it to Yes, and at the same time we set Enable Mitel Proprietary SDP to No.  Everything else we left alone.

Almost immediately, our problems came to an end. Calls to numbers that would fail every 2nd or 3rd attempt suddenly worked without error every single time. Another side benefit was that we were now getting music on hold when transferring to Mitel call queues, where we weren't before.

I was amazed that we had brought up the issues around both music on hold and the failed calls on numerous occasions, and the Mitel partner could not find a solution, while someone with zero experience with Mitel was able to find a solution in under 10 minutes of poking around.

I was feeling pretty good about fixing that issue, so I tried to solve the other remaining issue where outbound calls would only show the main office number rather than the individual Lync user's DID. However, my beginners luck ran out and I couldn't find a solution.

So, if you're having similar issues with a Mitel - Lync deployment, hopefully this will steer you in the right direction.

Inter-trunk Routing in Lync 2013

Introduction - What is Inter-trunk Routing?

Inter-trunk routing is a new feature in Lync 2013 that allows Lync Server to be the central call processor for a multi-PBX deployment.  In previous versions, Lync was only capable of being the final destination for phone calls.  If an inbound phone call couldn't be matched to a Lync user, the call would fail.  There was no way to have Lync forward calls on to another PBX, which limited the configuration options available to administrators.

Inter-trunk routing gives Lync administrators the ability to take calls in from a variety of sources and forward them on to other non-Lync destinations if there isn't a matching Lync user with the target phone number. 

The Problem

Recently, I had to deploy inter-trunk routing for a Lync deployment that had calls coming in from a variety of sources to a centralized Lync Server 2013 Enterprise Edition deployment:

• a Lync-certified SIP trunk
• a Canada-based T1 line connected to a PSTN gateway
• two US-based Mitel PBXs. 

The inter-trunk routing requirements were very specific: forward four phone numbers entering Lync from the SIP trunk to one of the US-based PBXs.  The four phone numbers were +1 (289) 555-3926, +1 (289) 555-6733, +1 (289) 555-6734 and +1 (289) 555-6780.

The Solution

Having never done Lync inter-trunk routing, I turned to the trusty Internet for answers.  I found lots of information on WHAT Lync inter-trunk routing was all about, but almost nothing on exactly HOW to configure inter-trunk routing in Lync.  I saw references to assigning PSTN usages to trunks, and saw the place in the Lync Control Panel to add it, but nothing but vague allusions to the process of actually implementing it.

UPDATE 10-June-2013: Richard Brynteson posted a more knowledgable deep-dive into inter-trunk routing mere days after I posted this. I made a slight adjustment to my process based on what I read in his blog, so its definitely worth reading.

As usual, when I come across such a situation, I assume that it must be so simple to configure that it didn't occur to anyone to actually document the HOW.  I then assume I must be a complete idiot for not knowing something so plainly obvious to every other Lync administrator on the planet. So, after much flailing around, I figured out a solution that works using inter-trunk routing.

Since I wanted to route only four specific phone numbers between trunks, I needed to make sure that I enabled inter-trunk routing for those numbers and no others.  If I allowed inter-trunk routing for too wide a range of phone numbers, we could get into a situation where calls could enter Lync, pass onto the target PBX and route back into Lync, causing a call loop.  Rather than leave it to the target PBX to ensure a call loop doesn't happen, I figured it best to ensure Lync only pass the specific numbers to the PBX.

I started by editing the site-level voice policy attached to the Lync site where the incoming SIP trunk calls came into Lync.  I created a dedicated PSTN usage/route combination for those four numbers.  The PSTN usage was called NA-ON-Cooksville-289555-MitelForward to keep with the naming convention used by the Lync Dialing Rule Optimizer.  The route was called NA-ON-Cooksville-289555-MitelForward with a route pattern of ^\+1289555(3926|67(33|34|80))$ pointing to the PBX at 1.1.1.1. 

The PSTN usage was placed at the very top of each voice policy's PSTN usage list to ensure that any Lync user that tries to dial those numbers will forward the calls to the desired PBX. For good measure, I also added the PSTN usage to the Global voice policy, although I'm not sure this is necessary.

Next, I assigned the new PSTN usage to the incoming SIP trunk under Trunk Configuration.  If the trunk doesn't exist, add it as a new pool trunk.  I then added a trunk for the PBX and added trunk translation rules to strip the number down to 5 digits, which is what the target PBX is expecting.

Once done, I committed the changes and waited a few minutes for the changes to bake to a nice golden brown.

The moment of truth came when I was able to call one of those four numbers and listen as Lync seamlessly passed the calls onto the Mitel PBX.  Great success!

Conclusion

I'd like to say it was my deep, Yoda-like knowledge of how call routing works in Lync that allowed me to think through the process of determining how inter-trunk routing works. Unfortunately, the truth is that I tried random combinations of things until I stumbled blindly onto the solution.  There's a reason why I chose that picture of the Hoff looking vacant and stunned at the same time as my avatar....it's how I look and feel much of the time.

To summarize the process:

1. Create a PSTN usage/route combination that is specific to the phone numbers required to be forwarded to the PBX.
2. Place the PSTN usage at the top of all voice policies to ensure that both inbound calls from the PSTN and calls made by internal Lync users are routed to the proper destination.
3. Assign the PSTN usage to the incoming trunk.

When complete, the whole call process should function as follows:

1. Inbound call comes into Lync via SIP trunk.
2. Lync normalizes the number into an E.164 phone number
3. Lync does a reverse number lookup to check for a Lync user with the same number
4. If no match in Lync, then it looks for a matching usage/route assigned to a trunk
5. When found, applies any outbound normalization rules and sends the call to the next hop

For a more detailed description on how the call flow will proceed, check out the Mastering Lync blog.  Richard Brynteson did a series on the nitty gritty details behind dialing behaviours in Lync. His post on Inter-trunk dialing is a deep-dive into the details that I don't get into here.

If there's anyone else out there trying to figure out how to implement Lync inter-trunk routing, I hope this helps figure things out.  As always, if you have any questions or can correct any misunderstanding I might have on the process, just leave a comment.

Viewing Extensions in the Lync Client

In companies that use extensions off the main number, I’ve always recommended they format their numbers using the main office number for the “base” and followed by the extension (ie. tel:+14165551111;ext=222 for North America, or tel:+4420555111;ext=222 for elsewhere).  In Active Directory, I’ve recommended they use the same type of format (ie. +1.416.555.1111 X222), and use the Company_Phone_Number_Normalization_Rules.txt to enforce the same formatting.

Background

For those unfamiliar with how Lync displays phone numbers, the Lync client will only display numbers it can parse from Active Directory.  It doesn't show the actual TelURI defined in the Lync Control panel, which is a good thing, because there are often additional settings applied there that administrators don't want to have appear in the address list.  The Company_Phone_Number_Normalization_Rules.txt file is helpful in re-formatting phone numbers in AD to the E.164 format we like to see in Lync.  For a good overview of the Company_Phone_Number_Normalization_Rules.txt, see Jeff Schertz's blog entry on the topic.

The Problem

I've found that when using the Lync 2010 client, North American phone numbers would always display with the typical North American formatting properly along with the extension when dialed, (ie. +1 (416) 555-1111 X222).  However, when applying similar rules to international numbers, the extension would never display.  It would show +4420555111 instead of +4420555111 X222.  The number would be dialed properly, but it would be confusing to the user, because the extension wouldn't appear.

Fast forward to Lync 2013 client, and the situation appeared even worse.  Even North American phone numbers with extensions wouldn't appear properly when dialled.  I assumed this was a client bug that was getting worse with each client revision.

The Solution...Sort of

Fellow Lync MVP Tom Pacyk of ConfusedAmused.com brought to my attention a little known (well, little known by me) feature added with the October 2012 update for the Lync 2010 client.  In short, the client update finally fixed the bug for international extensions, but with a catch....you had to first add a new client policy entry to your Lync client policy.  If only the global client policy is being used, the commands are:

$x = New-CsClientPolicyEntry -Name "ShowExtensionInFormattedDisplayString" -Value "True"
$y = Get-CsClientPolicy -Identity Global
$y.PolicyEntry.Add($x)
Set-CsClientPolicy -Instance $y

Since this policy setting was a part of the Lync 2010 client updates, it would be very easily missed by someone whose focus has changed to Lync 2013.  I can only assume the same settings are required in a pure Lync 2013 environment, although there is very little information on the topic.

If you're running Lync Server 2010, it appears as though you need at least the October 2012 Lync 2010 server updates for this to work.  I tried to apply this client policy entry to a client's deployment whose got Lync 2010 and 2013 in parallel, but the Lync 2010 environment is a bit out of date.  The policy entry showed up properly when I ran the following:

$y = Get-CsClientPolicy -Identity Global
$y.PolicyEntry

...but neither my Lync 2010 or 2013 clients would show extensions properly.  Applying the policy entry to a 2010/2013 server mix where the 2010 environment was up-to-date worked fine...at least for 2010 clients...mostly.

So, make sure your Lync 2010 infrastructure is up-to-date before attempting to apply this setting.

What's Still Not Working

I setup a few test users with extensions off a fictitious Toronto, Canada and London, UK main office number.  The Toronto user's office number in AD was set to +1.416.555.1111 X111, and the London user's number in AD was set to +44.20.444.2222 X999.  Both users were setup in Lync with their TelURI properly defined as tel:+14165551111;ext=111 and tel:+44204442222;ext=999 respectively.

A Company_Phone_Number_Normalization_Rules.txt file was placed in the ABFiles folder on the shared folder for the Lync server pool with the following rule to ensure Lync would be able to parse phone numbers  with extensions in Active Directory properly:

\+(\d{6,14})\D+(\d+)
+$1;ext=$2

When testing with the Lync 2010 client, North American numbers showed up properly in both the list view and the dialing view, as shown below:

However, international numbers did show numbers a bit differently between the views, using the ;ext= from the TelURI instead of the X:

Interestingly enough, the Lync 2013 client doesn't seem to fully honour the extension setting for either North American or international numbers.  The number shows up properly when hovering over the phone icon, but only shows the main number when dialing:

North America

United Kingdom

Needless to say, this can be very confusing to the average user.

This appears to be a bug introduced with the Lync 2013 client.  I've brought this up with the Lync product managers, and we should see a future patch that will address the issue for Lync 2013 clients.

Location-Based Routing in the Lync Optimizer

The Lync Server Update for February 2013 included a much asked for feature: location-based routing. Location-based routing basically ensures the routes that phone calls can take are dependent on where the user is currently located.

Before the February 2013 update, the path calls would take were solely determined by the assigned Lync voice policy.  Normally,  call routes are somewhat local to the user (at least within the same country). If a user were to go to another office on the other side of the planet, their calls would still route via the same paths as if the user were at their home office.

Normally, this isn't a very big issue, but some countries have very strict rules about how calls may enter and exit the country. India is an example where they don't want to see any calls leave the country via the Internet.  All calls must leave the country via the PSTN.  Toll bypass or least-cost routing is not allowed.

Fellow Lync'er Richard Brynteson wrote up a great post on how to setup location-based routing in Lync 2013 CU1.  He even put me on the spot by saying that I was working on adding location-based routing to the Optimizer.  So, that pretty much meant that I had to do it.

So, in the spirit of the Lync Optimizer doing all the work required to setup Enterprise Voice in Lync, I've added an option to configure location-based routing when the Optimizer is run for a given Lync deployment.

There is a single prerequisite in order to make it all work. The Lync environment must have at least one Lync network region, site and subnet configured (preferably/obviously for the location where location-based routing is to be enabled).  If call admission control has already been deployed, then this should already be done.  If not, the Lync network site/subnet can be setup manually by following the guide on Technet. If AD Sites & Services has been fully populated with site/subnet information, I've created a script that will transfer this into Lync.

When the Optimizer runs, it will check to see if the deployment is running Lync 2013 and has at least one network site defined.  It will then prompt the user to apply location-based routing to that site (or others if more than one site is found).

If you are unsure whether or not to apply location-based routing, then DON'T DO IT.  It will ensure that all calls made from within the network site use only the routes defined for that site.  It may have unintended consequences for users visiting the site.  It can be undone, but if you are not comfortable with the inner workings of Lync, its best not to open up that can of worms.

As a final note, the Lync Optimizer now includes dial rules for India, which is one of the main reasons why location-based routing was added to Lync in the first place.

Best of luck out there!

Automatically Creating Lync Sites and Subnets using AD Sites

To use call admission control or location-based routing in Lync, one of the first steps is to define all the sites and subnets used in the company and to assign the sites to network regions.  In larger companies, this can be a tedious process if this information is not stored in a central, easily accessible location.

One place where network site/subnet information can sometimes be centrally found is within Active Directory itself.  Active Directory and other applications such as Exchange uses site/subnet information to determine where to direct clients for authentication services (among other things).  Ideally, every site and subnet should be defined using the Active Directory Sites and Services snap-in.  If the Active Directory administrator has diligently defined all the sites/subnets, this information can be easily parsed and used in Lync.

I've created a short script that will automate the creation of network sites and subnets using the information stored in AD Sites and Services.  Again, this script is only useful if all the sites/subnets have been defined in AD.  Thanks to Greig Sheridan who fixed the script to deal with AD site names that have characters that are invalid for Lync site names (such as underscore).

Copy the below script into a .PS1 file on a Lync server and run it.  As always, be careful and test this in a lab first.  I can't be responsible for any damage this script will cause.
# Load Active Directory Powershell module if its not already loaded if(-not(Get-Module -name ActiveDirectory)){Import-Module ActiveDirectory} # If a Lync network region doesn't exist, create one and name it the same as the first Lync site # If one or more does exist, select the first one associated with the first Lync site if(-not(Get-CSNetworkRegion)) { $SiteName = (Get-CSSite 1).DisplayName New-CSNetworkRegion $SiteName -CentralSite 1 } else { $SiteID = (Get-CSSite 1).Identity $SiteName = (Get-CSNetworkRegion | Where {$_.CentralSite -eq $SiteID} | Select-Object -First 1).NetworkRegionID } # Get the ConfigurationNamingContext from AD and go to the Sites container $ConfigDN = (Get-ADRootDSE).ConfigurationNamingContext $SiteContainerDN = ("CN=Sites," + $ConfigDN) # Select all the site objects $Sites = Get-ADObject -SearchScope OneLevel -SearchBase $SiteContainerDN -filter {ObjectClass -eq 'Site'} foreach ($Site in $Sites) { # Create Lync network sites based on AD site $SiteObj = Get-ADObject $Site.distinguishedName -properties "siteObjectBL", "description" New-CSNetworkSite -NetworkSiteID $SiteObj.Name -Description $SiteObj.Description -NetworkRegionID $SiteName # Add each defined AD site subnet to the Lync network site object foreach ($SubnetDN in $SiteObj.siteObjectBL) { $Subnet = Get-ADObject -Identity $SubnetDN -properties "description" $SubnetName = $Subnet.Name #Subnet name is in format 192.168.100.0/24 $SubnetSplit = $SubnetName.Split("/") #Need to split subnet name into IP and mask for command $SubnetID = $SubnetSplit[0] $SubnetMask = $SubnetSplit[1] New-CSNetworkSubnet -SubnetID $SubnetID -MaskBits $SubnetMask -Description $Subnet.Description -NetworkSiteID $SiteObj.Name } } #Create subnet object with 32-bit mask for all public edge A/V IP addresses $EdgeServerPools = Get-CSService -EdgeServer | Where {$_.SiteID -ne "Site:BackCompatSite"} foreach ($EdgeServerPool in $EdgeServerPools) { $EdgeServers = (Get-CSPool $EdgeServerPool.PoolFQDN).Computers foreach ($EdgeServer in $EdgeServers) { $NetworkInterfaces = Get-CSNetworkInterface -ComputerFQDN $EdgeServer | Where {$_.Interface -eq "External" -and $_.IPAddress -ne "0.0.0.0"} if (($NetworkInterfaces).Count -eq 3) { $NetworkInterface = $NetworkInterfaces | Where {$_.InterfaceNumber -eq 3} } else { $NetworkInterface = $NetworkInterfaces } if ($NetworkInterface.ConfiguredIPAddress -ne $NULL) { $IPAddress = $NetworkInterface.ConfiguredIPAddress } else { $IPAddress = $NetworkInterface.IPAddress } $Description = "A/V external edge IP for " + $EdgeServer New-CSNetworkSubnet -SubnetID $IPAddress.IPAddressToString -MaskBits 32 -Description $Description } }

The script will first check to see if a Lync network region already exists. If so, it will select the first one it sees as the base for all the subnets.  If one doesn't exist, it will create one using the first Lync site as the base. If need be, you can define additional network sites later.

The script will then create all the sites/subnets based on information from AD. All the sites will be assigned to the one network region selected according to the rules in the previous paragraph. Since there is no way for the script to know which site belongs to which region, this will have to be done manually if multiple Lync network regions exist.

IMPORTANT: The script will also create the required subnets for all the Lync edge A/V public IP addresses with a 32-bit subnet mask as per the requirements for call admission control.  You will have to manually assign these subnets to the sites where you deployed the edge servers.

While this script doesn't try to do everything associated with setting up call admission control, it does go a long way towards automating a good chunk of the process. A future revision of the Lync Optimizer will hopefully close the loop and help completely automate the work required to setup location-based routing.

As a final side note, one thing I don't understand is why Lync can't leverage AD Sites & Services for this information directly.  Exchange versions since 2007 have used AD Sites & Services for mail routing, so its not like it hasn't been done before.  Maybe a future version of Lync will add this functionality.  Until then, this script should help those who have well-defined site/subnet information in Active Directory.

Assigning a Throttling Policy to all iOS 6.1 Devices in Exchange 2010

UPDATE 14-Feb-2013: After being linked to from Ars Technica, I felt the need to improve the script. My original version of the script tried to use the UserDisplayName field that is returned from Get-ActiveSyncDevice.  However, that field had a maximum number of characters, and a number of longer user DNs got cut off, which would make the script fail for that user. I figured out a way around it, and the script has been updated.

If you're an Exchange administrator, you have probably heard about the issues caused by Apple's iOS 6.1 on Exchange servers.  It seems that screwy calendar code in iOS 6.1 ends up generating tons of transaction logs in Exchange, and can bring CAS servers to its knees.

As an aside, its rather timely that this has come up just after the new Blackberry 10 came out.  Coincidence??????  Heh.

The temporary workarounds that MS recommends were to either apply a throttling policy to affected users, or block iOS 6.1 devices completely.  Since an all-out block is generally a Bad Thing, throttling policy is the way to go.  However, determining who is using iOS 6.1 and applying a throttling policy to them was not provided.

A company I do work for experienced the exact issue.  Exchange transaction logs were being generated at a prodigious rate.  So, rather than blocking them, we went the throttling route.  First, I created a throttling policy called iOS61 and set the ActiveSync throttling to the lowest recommended values:

New-ThrottlingPolicy -Name iOS61 -EASPercentTimeInCAS 10 -EASPercentTimeInAD 10 -EASPercentTimeInMailboxRPC 10

Then, I created a short Powershell script to apply the policy to any user with a device using iOS 6.1:

$DeviceList = Get-ActiveSyncDevice -ResultSize Unlimited | Where {$_.DeviceOS -match "iOS 6.1"}
foreach ($Device in $DeviceList)
{
$DeviceDN = $Device.DistinguishedName
 $MBName=$DeviceDN.SubString($DeviceDN.IndexOf("CN=ExchangeActiveSyncDevices,")+29)
Set-Mailbox $MBName -ThrottlingPolicy iOS61
}

The script will likely throw up some warnings about completing the command but not making any changes.  This happens because users may have more than one device, and the script tries to update the mailbox for every device it finds.  Nothing to be alarmed about.

Quick and dirty, but gets the job done.

Once Apple comes up with a solution, you can remove the throttling policy like this (assumes the users didn't have a throttling policy before this whole debacle):

Get-Mailbox -ResultSize Unlimited | Where {$_.ThrottlingPolicy -eq 'iOS61'} | Set-Mailbox -ThrottlingPolicy $NULL

Limiting Call Forwarding and Simultaneous Ringing in Lync 2013

In Lync 2010, users were able to forward calls or setup simultaneous ringing to any number that they were able to call themselves.  This could lead to people forwarding all their calls to a long distance or even international number (assuming their voice policy allowed international calling).  This can lead to increased telephony costs to the company, and there wasn't very much the administrator could do to control this, short of disabling the feature entirely.
A new feature in Lync Server 2013 Enterprise Voice allows administrators to limit where users are able to setup call forwarding/simultaneous ringing.  You'll see the new option at the bottom of the voice policy screen in Lync 2013 Control Panel (as highlighted in red).

The selectable options are:

Route using the call PSTN usages (default) - essentially means to allow users to forward calls to any destination phone number they are allowed to call (the same behaviour as in Lync 2010).  So if a user is allowed to call international numbers, they will be allowed to forward/simultaneous ring international numbers. The option wording here could really use some improvement, because to me it doesn't make much sense as it currently stands.
Route to internal Lync users only - allows call forwarding/simultaneous ringing only to other Lync users within the company.
Route calls using custom PSTN usages -  allows administrators to limit call forwarding/simultaneous ringing to only the PSTN usages defined by the administrator.

When the last option is selected, the Control Panel will display a box where administrators can select the appropriate PSTN usages.  For instance, to limit call forwarding/simultaneous ringing to only local numbers, select a local PSTN usage, as shown below:

Administrators can add multiple usages to allow calls forwarding/simultaneous ringing to any combination of PSTN usages.  Since voice policies can be applied either globally, site-wide or down to the user level, this should allow administrators to grant different policies to any number of users.

This assumes the Enterprise Voice deployment has been designed granular enough to break out local, national and international calling.  If there is only a single catch-all usage for all calls, then this won't work and the Enterprise Voice configuration will have to be re-designed.

Luckily, the Lync Dialing Rule Optimizer (shameless plug) creates usages for local, mobile, national, premium, and international usages, which should be enough for any administrative need.

Unfortunately from the user's perspective, they won't get a notification in the Lync client if they try to forward/simultaneous ring a phone number that is outside the dialing areas allowed by their voice policy.

For example, assume a user's voice policy only allows forwarding/simultaneous ringing to local numbers. If the user sets up simultaneous ringing to a number outside the local dialing area, they won't get any feedback that it isn't allowed by the policy.  When someone phones the user, their Lync devices will ring as usual, but the simultaneous ring number simply won't ring.  This could generate an unnecessary helpdesk call, which could also confuse the helpdesk, if they haven't been made aware of the policy.

Similarily, the user doesn't get any feedback in the Lync client when setting up call forwarding to a number outside the allowed dialing areas.  In this case, calls will simply go straight to Exchange voicemail without attempting to forward.  However, the user will get an email stating the forwarding isn't allowed.  Slightly more helpful, but still likely to generate a helpdesk call.

Curiously, the interface still refers to Office Communicator, but since I'm still running Exchange 2010, maybe this is to be expected.

The situation would be greatly improved if the Lync client would be more informative in this respect.  In my perfect world, there would be no war, global warming would turn Canada into a tropical paradise, gin and tonic would flow freely from taps all around my house, and the Lync client would provide feedback like this when users try to forward to a number that isn't allowed:

A man can dream, can't he?

Either way, the new control administrators have to limit call-forwarding/simulring is a much needed new feature, and I'm glad it made it into Lync 2013.

Least-Cost/Failover Routing in the Lync Dialing Rule Optimizer

The Lync Dialing Rule Optimizer tries to take care of all the Enterprise Voice configuration necessary for all deployments.  On most fronts, it does a pretty good job (IMHO).  One area that has been lacking is the ability to automatically arrange PSTN usages to provide least-cost/failover routing for multi-site Lync deployments. Once an administrator has run the Optimizer for all their sites, they have to manually configure the voice policies to provide least-cost/failover routing.

If you're not familiar with how least-cost/failover routing works in Lync, please refer to my post on the subject in my Lync Enterprise Voice Best Practices series.

With version 9.0 of the Lync Dialing Rule Optimizer, Lync administrators now have the option to create least-cost/failover routing between all sites that have been deployed using the Optimizer (or at least follows the same naming conventions used by the Optimizer).

When the Optimizer-generated script detects multiple Lync sites, it will prompt the user if they want to apply least-cost/failover routing to the voice policy being generated.  If the user allows it, the Optimizer will add PSTN usages for all the other sites to the new voice policies.  This assumes the existing PSTN usages are named with the country abbreviation first, and ends with either Local, National, International etc in any of the languages currently supported by the Optimizer as in the following examples:  UK-Leeds-113-Local, IT-Rome-06-Nazionali.

The output can be best summarized by way of example.  Assume a company has Lync Enterprise Voice deployed in the following locations:

Toronto, Canada

Vancouver, Canada

London, UK

Rome, Italy

Belém, Brazil

After running the Optimizer script against all sites, the PSTN usages for the Toronto International user voice policy would look like this (you might want to sit down for this):

NA-ON-Toronto-416567-Local

NA-BC-Vancouver-604678-Local

NA-ON-Toronto-416567-National

NA-BC-Vancouver-604678-National

NA-ON-Toronto-416567-Premium

NA-BC-Vancouver-604678-Premium

NA-ON-Toronto-416567-Service

UK-London-20-Local

IT-Roma-06-Locali

BR-Belém-91-Local

UK-London-20-Mobile

IT-Roma-06-Cellulari

BR-Belém-91-Celular

UK-London-20-National

IT-Roma-06-Nazionali

BR-Belém-91-Nacional

NA-ON-Toronto-416567-International

NA-BC-Vancouver-604678-International

UK-London-20-International

IT-Roma-06-Internazionali

BR-Belém-91-Internacional

The Optimizer will group PSTN usages from the same country near the top, using the assumption that most of the calls will be made to in-country locations and that the fewer PSTN usages the system needs to evaluate for each call, the better.

The ordering is such that least-cost routing and failover routing will occur.  PSTN usages from other countries will be placed lower in the list while still providing least-cost and failover routing for all calls.  If there are multiple Lync sites out-of-country, the ordering of PSTN usages within the National and International usages will be somewhat random. Administrators should review the PSTN ordering to make sure it suits their needs.

It is assumed that premium numbers can only be dialed from in-country locations, so out-of-country premium PSTN usages are not assigned. Also, only the local service PSTN usage is assigned for similar reasons.

All calls will use the least-cost route where possible. If a route assigned to a specific usage is unavailable, calls will use a route in another site, again keeping the call in-country if possible.

With the inclusion of least-cost/failover routing in the Lync Optimizer, administrators now have a tool that can completely build the Enterprise Voice environment for even the largest enterprise-level Lync deployment.

As always, feedback is greatly appreciated. Let me know if you come across any issues with functionality or scalability as I haven't tested if there is a limit to the number of PSTN usages that can be assigned to a voice policy.

Blocking International Calls to Specific Countries in Lync

A question that often comes up in my travels is that Lync administrators want an easy way to allow users to dial internationally but exclude specific countries for some reason.

This is very easy to accomplish once you understand the ins and outs of regular expressions, and assuming you follow all my best practices regarding number normalization, and Enterprise Voice setup.  To summarize, every number a user enters in Lync should be normalized to E.164 standards, which starts with a + followed by the country code, then the area/city code and finally the local subscriber number.  A Canadian example (country code 1) would be +14165551111.  A UK example (country code 44) would be +442033334444.  If you use the Lync Dialing Rule Optimizer to create your Enterprise Voice configuration, you'll be all set.

When all numbers are normalized to E.164, and you already have separate usages and routes for local, national and international calls, it makes it very easy to design regular expressions that meet any specific criteria required by your business.

Say your company is based in North America, and is required to block international calls to Iran (98) and North Korea (850).  The Lync Dialing Rule Optimizer routing rule for international calls is this:

^\+[2-9]\d{6,14}$

This rule allows any number that doesn't start with a 0 or 1 to be routed out. Only North American countries (US/Canada and some Caribbean countries) use the country code 1.  All other country codes start with the digits 2-9.  So essentially, this rule allows calls to any international destination.

To block calls to Iran and North Korea, modify the rule to look like this (new stuff highlighted in yellow):

^\+(?!98|850)[2-9]\d{6,14}$

This will allow any number starting with 2-9, but excludes numbers that start with 98 or 850 as required.

If you're not in North America and used the Lync Dialing Rule Optimizer to create your Enterprise Voice setup, your international rule looks a little different, because we want to make sure that North American numbers are formatted correctly (as highlighted in blue), while making sure that it does not try to route national numbers as international (using UK +44 as an example, shown in green):

^\+((1[2-9]\d\d[2-9]\d{6})|(?(?!(44))([2-9]\d{6,14})))$

To block calls to Iran and North Korea using this example, modify the rule as follows (new stuff highlighted in yellow again):

^\+((1[2-9]\d\d[2-9]\d{6})|(?(?!(44|98|850))([2-9]\d{6,14})))$

Now, anybody who tries to dial a number in Iran or North Korea will be met with a notice that the call couldn't be completed.

This method is pretty granular as you could create separate routes to block countries selectively or for a specific group of users.  If you want to just block those numbers globally, you can use Unassigned Numbers to provide an announcement to users that those numbers are not allowed to be dialled. The only downside to that method is that you need to know in advance how long phone numbers are in the country you want to block.

Happy Enterprise Voicing everyone!

Localized UK Dialing Rules for the Optimizer

Using data from a number of web sources and some helpful users, I've been able to create customized Lync dialing rules for over 30 countries worldwide and made them available to all via the Lync Dialing Rule Optimizer.  These customized dialing rules account for country-specific dialing patterns for local, national, international, toll-free, mobile, premium and service numbers.

However, true localized dialing rules have been out of reach for countries other than those in North America until now.  For all non-North American countries, I have been forced to create generic dialing patterns for local numbers simply because I don't have access to any source of local dialing rule data.  This isn't generally a problem because most local dialing rules are different enough from other patterns that conflicts are rare.  For example,  a local dialing rule for a country might specify that the number start with digits 2-9 and are between 5 and 6 digits in length.  As long as there aren't any other dialing patterns in that country that use that same pattern (ie national, international, mobile, service, toll-free or premium), there won't be a problem.  I try to make sure that is the case for all dialing rules created for the Optimizer, but it is sometimes difficult.

The United Kingdom has more than 60 different local dialing rules. Local numbers can be 4 to 8 digits in length and area codes have from 2 to 5 digits. Some 41 area codes have mixed length numbers where some numbers have a total 10 digits and others have only 9. In some area codes the local number cannot begin with certain digits, or certain digits will not come into use for many decades.  The generic UK local dialing rule used by the Optimizer tries to account for all these in a single regular expression, but obviously some generalizations had to be made.

Enter Ian Galpin of the UK.  Ian has made it a personal mission to ensure that the UK has a complete set of dialing rules written as regular expressions.   Over the past year, he's helped me ensure the regex for UK dialing rules are correct.  He's also created a localized set of dialing rules for every area code in the UK as an XML file along with a list of all the area codes used in the UK.  He's done this to help various telephony vendors create the appropriate rulesets for PBX deployments. I've been able to incorporate that into the Lync Dialing Rule Optimizer, so that UK users now have true customized local dialing rules for Lync that will differ depending on which area code you select in the Optimizer.

I've modified the Optimizer code to be able to use local dialing rules for other countries if available.  If anybody can point me to a similar source as provided by Ian for other countries, it would be greatly appreciated.