Mino – The UC Guy

Microsoft Unified Communications Blog

Posts Tagged ‘lync 2010’

Lync by LINK , Full Lab Setup at Microsoft Egypt premises

Posted by Mino on November 16, 2010

Last week we built Lab setup for Lync at Microsoft Egypt premises , Fady Eskander from our technical team in LINK Development was responsible for it and I was helping. The aim of this setup was to showcase Lync up and running fully featured but more from the end user  experience .

For this we simulated 6 different types of users , each on his desk with different endpoints even for the same user. I can tell you that whoever walked in that room to give it a try was really impressed and mostly with the wide range of endpoints and how flexible it is to just unplug and plug devices between different users … Yes Lync rocks and that’s a Fact .

I just thought to share with you some photos of the setup , excuse us if it was not yet clean but these shots were taken at the testing stage and not the final one 🙂

For our setup we used the following :

  • IBM Server ( 24 GB RAM ) , holding all VMs ( DC, Exchange, SQL , Lync FE , Lync Monitor, SharePoint)
  • 6 Notebooks ,for 6 types of users where each is on his desk
  • NET media gateway , VX1200 mainly for the SIP server built in on that box. we used SIP to register non Lync sip phones and also we used it for Nokia & Blackberry phones to make Wifi VOIP calls through SIP clients ( Ooooh that was really worth testing )
  • NET media gateway , Tenor AF mainly for FXS and FXO ports . we connected Old Analog phone ( my favorite Old Phone 🙂 )
  • Ericson PrimaCell gateway , this is a GSM gateway where u just put your mobile SIM card and connect it on FXO port. we used it to place inbound and outbound calls ( very useful for moving demos , u don’t need to ask the client for testing line )
  • Polycom Phones ( CX700 , CX500 , VVX ,RoundTable  )
  • Aastra Phone (6725ip)
  • Plantronics endpoints (Savi W430-M Bluetooth , Blackwire C420-M USB headset ,Calisto P420 USB speaker ,Calisto P210-M USB handset)
  • Jabra endpoints ( Jabra GO™ 6400 , Jabra GN9300e , Jabra M5390 )
  • Microsoft Web Cams ( HD Cams & 2MP Cams )

Now I can leave you with the photos


This user got Polycom CX500 , also 2 Plantronics endpoints ( External Speaker ) , ( Bluetooth headset )


This user got Aastra phone , Polycom ( RoundTable ) ,also connected to it Plantronics Savi W430-M( Bluetooth headset ) , ( Handset lifter ) Oooh that lifter really looked cool when you answer the calls through the Bluetooth headset it just lifts the handset up to pickup the call and once you finish it places it back down..


This user simulated the call center agent , he is part of Lync response group which we created for helpdesk. as an agent he is using Polycom ( CX300 ) USB phone and connected to it is Plantronics Blackwire C420-M ( Headset )


This user got Polycom ( CX700 ) touch screen phone with Lync firmware installed , also connected to it is Jabra GN9300e  (Bluetooth headset )



This user is using Polycom Video phone ( VVX ) , this phone is not optimized to Lync usage however it is registered through SIP over the media gateway and also it can provide point to point video calls. The user also is using Plantronics Calisto P210-M ( USB handset )


This is just to show you the round table on full screen , the quality is really great and I wanted so much to give it a try on Plazma screen.


And Finally , the backstage setup with the Macaroni cables 🙂 . yes we all know that look and somehow we got used to it.

Lync launch is tomorrow and I am so excited for it just like all of you , cuz I know its gonna be a great year and we will definitely give hard time for Cisco and Avaya ….Booo 🙂

Posted in Lync 2010 Client, Lync Phone, Lync Server 2010, Lync Telephony | Tagged: , , , , , , , | 9 Comments »

How to allow domain users to connect to Lync 2010 or OCS 2007 from Clients running on non-domain computers

Posted by Mino on September 15, 2010

I had a situation in our company where we have exceptional few users who got Domain credentials but they are working on Computers that are not joined to the domain.

However these computers run over the LAN or WAN, can communicate with the internal DNS and got the certificate chain of the CA imported to them and they use DOMAIN\UID and password credentials to login to mail , MOSS and everything is working fine.

When I installed the OCS 2007 R2 client on their machines and tried to login with the same behavior as mail using DOMAIN\UID , I was not able to log in and I received the below event log warning:

"Communicator was unable to authenticate because an authenticating authority was not reachable.”
The server may be asking for Kerberos authentication and Communicator is not able to find the Kerberos Domain Controller in order to generate credentials and authenticate.  The network administrator will need to change the configuration on the server to utilize only NTLM authentication before Communicator can login from this location properly, or connectivity will need to be made available to an authenticating authority"


also as for testing I removed the OCS 2007 R2 client and installed the new Lync RC client on the same machine , I know it is not supported scenario but I was just testing it. Now the user was able to login but it disconnects after 10 seconds then reconnects again , it keep in this loop. I also found the same warning in the event log.

I know why this is happening and I know it would have been solved from the beginning if i forced the OCS to use NTLM only rather than Kerberos but this was not something i can force.

So in the end the Solution was this problem was simple :

Ensure that the users when singing in to communicator 2007 or Lync 2010 to include the ".local" in the domain.local\username part of the authentication and not DOMAIN\username.

Posted in Common Errors, communicator client, Lync 2010 Client | Tagged: , , , | 3 Comments »

Microsoft Lync Server 2010 Media Bypass

Posted by Mino on September 14, 2010

What is it?
  • Media Bypass allows for Lync clients to communicate directly with a qualified PSTN voice gateway or qualified IP-PBX without traversing the Mediation server for media transcoding

  • When clients use Media Bypass, the Lync client uses the G.711 codec over SRTP

What are the benefits?
  • Greatly simplifies topology
    • Allows for Mediation server to collocate with Front End server or SBA because of low CPU intensity
    • Greatly reduces the amount of servers needed in deployment resulting in lower TCO
  • Optimizes media flow and quality
    • Eliminates unnecessary hops and potential points of failure
    • Saves WAN bandwidth
    • Improves voice quality with use of G.711 codec

However to enable Media Bypass ,you must ensure that either the Media Gateway ( SBA ) or the IP-PBX does support the Media Bypass feature.

Below are some different scenarios for the Media bypass between 2 sites:

First Scenario :

In this scenario the Client in the main data center dials a PSTN number, so the client communicates directly with the gateway using G.711 codec without the need to used the mediation for transcoding from RTaudio to G.711 Codec.


Second Scenario :

In this scenario the client is located in the branch site where there is no Lync Servers installed , when the client places a PSTN call it communicates directly with the IP-PBX over G.711 without the need for getting back to the Data Center pool mediation for transcoding. However this scenario is only applicable if your IP-PBX does support the new Media Bypass feature.


Third Scenario :

In this scenario we have two clients placing the call , one from the Data Center and the second is in Branch site. you will typically have this case in the international sites where you want to enable the least cost routing for international numbers. Lets say the Main Data Center is in US and the branch Site is in Egypt , and both Clients will dial the same number which is a US number.

So the first client who is in the US data center will communicate to the mediation server directly over G.711 , then the mediation will place the call through the Hosted SIP trunk to the PSTN also over G.711 since there is no local PBX available in the Data Center.

The Second Client who is in the Egypt branch site will dial the US number , the client will communication with the Mediation server place in the US Data center over RT Audio then the mediation will talk to the PSTN over G.711. In this second scenario we used RT Audio because it has got lots of features over the G.711 which consumes more bandwidth  , RT Audio gives much better quality over WAN due to correction mechanisms and the ability to overcome lost packets.


Forth Scenario :

In this scenario we have the same case like the last one , however we have also enabled Call Admission Control ( CAC ) which is a new great feature in Lync Server 2010. It allows call control over WAN to assure the accepted number of call over the allocated bandwidth and to refuse any extra calls over the allowed limit . What makes this CAC feature great also is not only to control calls over the WAN , but also to give alternate route for calls over the PSTN rather than using the WAN.

Ok let me explain it , the Client in the Egypt branch site is placing an international call to US number , so the client tries to place the call through the mediation placed in the US data center over the WAN , however due to WAN full usage and the CAC control ( call admission control ) so the call is not allowed to be placed over the WAN , however in spite of dropping the call we find that the client is redirected with alternate route to his local GW to place the call as international number from his PSTN gateway.


Fifth Scenario :

In this scenario the Client who is placed in the branch site places a call to a PBX legacy endpoint which is placed in the main site data center , this endpoint is connected to the IP PBX where this IP-PBX does not yet support direct Media bypass.

So the Client communicates over the WAN to the mediation server over RT Audio , then the call is routed after transcoding from the Mediation to the IP-PBX over G.711 , and finally the IP-PBX sends the call to the end point directly over G.711.


Posted in Lync 2010 Client | Tagged: , , , , , | 6 Comments »