Lync Server 2010 User Models
Topic Last Modified: 2011-07-17
The user models described here provide the basis for the capacity planning measurements and recommendations described later in this section.
Lync Server 2010 User Models
The following table describes the user model for registration, contacts, instant messaging (IM), and presence for Microsoft Lync Server 2010 communications software.
Environment and Registration User Model
| Category | Description |
|---|---|
Percentage of Active Directory users |
We assume that 70% of all Active Directory users in the organization are enabled for Lync Server 2010. 80% of those enabled users are logged on to Lync Server each day (80% concurrency). The concurrent users are the basis for the numbers in the rest of this section. |
Active Directory distribution groups |
We assume that the number of Active Directory distribution groups in the organization is equal to three times the number of all users in Active Directory. The distribution groups have the following sizes:
|
Voice over IP (VoIP) users |
50% of Lync Server users are enabled for unified communications (UC) (that is, their phone numbers are owned by Lync Server 2010). |
Registered client distribution |
65% of clients running Microsoft Lync 2010 clients, including Microsoft Lync 2010, Microsoft Lync 2010 Phone Edition, and Microsoft Lync 2010 Mobile. 30% of clients running either Office Communicator 2007 R2 clients or Office Communicator 2007 clients, including Communicator Web Access, Communicator Phone Edition, and Communicator Mobile. 5% of clients using Microsoft Lync Web App. Client multipoint of presence (MPOP) is 1:1.5, meaning that 50% of users have two clients signed in at the same time. |
Remote user distribution |
70% of users connecting internally. 30% of users connecting through an Edge Server, and a Director (recommended). |
Contact distribution |
The maximum number of contacts a user has is 1,000. Less than 1% of users have 1,000 contacts. Less than 25% of users have 100 or more contacts. Average of 80 contacts for users with public cloud connectivity. Of these users:
Average of 50 contacts for users without public cloud connectivity. Of these users:
|
Session time |
The average user logon session lasts 12 hours. All users log on within 60 minutes of the start of the session. |
IM and Presence User Model
| Category | Description |
|---|---|
Peer-to-peer IM sessions |
Each user averages six peer-to-peer IM sessions per day. 10 instant messages per session. |
Presence polling |
Overall, we assume presence polling at an average 40 polls per user per hour, with a maximum of eight per user per minute. For each user, assume an average of:
Presence publication is average of 4 per user per hour, with a maximum of six per user per hour. |
Presence subscriptions |
When one user adds another as a contact, the first user is subscribing to five categories of information about the second user. Updates of these categories of information are automatically sent to the first user. The user model assumes a default of 1000 category subscriptions per user. This means that a user could be a contact of as many as 200 other users. 1000 category subscriptions is also the default maximum. If needed, you can raise the maximum allowed to 3000. For details about changing this default, see Planning for IM and Presence in the Planning documentation. |
The following table describes the user model for address book use.
Address Book Usage User Model
| Address Book search mode | Usage |
|---|---|
Address Book Web Query only (all queries performed by Address Book Web Query service) |
Four prefix queries per user per day. 60 exact search queries per user per day. 40% of those are batched, with an average of 20 contacts per query. The other 60% of the queries are for a single contact. 25 photo queries per user per day. 24 are for a single photo, the other is a batch query with an average of 20 contacts. One total organization search query per user per day. |
Mixed mode, both address book file and web queries used. This is the default mode. |
Only two types of queries go to the network, the photo and total organizational search queries. 25 photo queries per user per day. 24 are for a single photo, the other is a batch query with an average of 20 contacts. One total organization search query per user per day. |
The following table describes the conferencing model.
Conferencing Model
| Category | Description |
|---|---|
Scheduled meetings versus "Meet now" meetings |
60% scheduled, 40% unscheduled. |
Conferencing client distribution |
For scheduled meetings:
For unscheduled meetings:
|
Meeting concurrency |
5% of users will be in conferences during working hours. Thus, in an 80,000-user pool, as many as 4,000 users might be in conferences at any one time. |
Meeting audio distribution |
40% mixed VoIP audio and dial-in conferencing, with a 3:1 ratio of VoIP users to dial-in users. 35% VoIP audio only. 15% dial-in conferencing audio only. 10% no audio (IM-only conferences, with an average of five messages sent per user). |
Media mix for web conferences |
75% of conferences are web conferences, with audio plus some other collaboration modalities. For these conferences, the other collaboration methods are as follows: Note These numbers add up to more than 100% because one conference can have multiple collaboration methods.
|
Meeting participant distribution |
50% internal, authenticated users. 25% remote access, authenticated users. 15% anonymous users. 10% federated users. |
Meeting join distribution |
Users are assumed to join a meeting at the following rates:
|
Lync Server 2010 has a maximum supported meeting size of 250 users. Each pool can host one 250-user meeting at a time. While this large meeting is occurring, the pool can also host other smaller conferences. For details, see the “Conferencing Maximums” section in Capacity Planning Requirements and Recommendations.
The following table shows the distribution of typical meeting sizes and durations
Conference Size and Duration Model
| Number of attendees (in addition to presenter) | % of total conferences | Average duration in minutes |
|---|---|---|
1 |
19% |
17 |
2 |
20% |
36 |
3 |
21% |
42 |
4 |
14% |
46 |
5 |
9% |
49 |
6 |
5% |
53 |
7 |
4% |
55 |
8 |
2% |
56 |
9-15 |
4% |
65 |
16-35 |
1% |
93 |
36-100 |
<1% |
100 |
The following table provides details about the user model for conferences involving dial-in users.
Dial-In Conferencing User Model
| Category | Description |
|---|---|
Authenticated/anonymous |
70% authenticated, 30% anonymous (and prompted for a recorded name). |
Transfer |
10% of dial-in callers are transferred to another pool. |
Call duration and music on hold |
Average call duration without music on hold: 50 seconds. 50% of call-in users hear music on hold, for an average of 5 minutes. |
Dual-tone multifrequency (DTMF) |
15% of conferences that are dial-in only have phone leaders. 10% of mixed conferences that include dial-in users also have phone leaders. 20% of phone leaders use 2 DTMF commands per conference. When the phone leader removes the mute everyone command, 50% of users then unmute themselves using DTMF. |
The following table provides details about the user model for conference lobbies.
Conference Lobby User Model
| Category | Description |
|---|---|
Number of users in lobby |
5% of dial-in users go through the lobby, and 25% of other users go through the lobby |
Admitting from lobby |
80% are admitted by presenter before client timeout. 10% are rejected by presenter before client timeout. 10% wait in lobby until client timeout. Average wait time in lobby is 5 minutes. |
The following table describes the user model for other peer-to-peer sessions.
Peer-to-Peer Sessions User Model
| Category | Description |
|---|---|
Application sharing |
Each user participates in 5 peer-to-peer application sharing sessions per month, for an average of 0.25 sessions per day. The average session lasts 16 minutes. |
File transfer |
Each user participates in 1 peer-to-peer file transfer session per month (as part of an IM session), for an average of 0.05 sessions per day. The average session file size transferred is 1 MB. |
Busy Hour
For peer-to-peer sessions, peak load is calculated using busy hour call attempts (BHCA). This voice industry term assumes that 50% of all calls for the day will be completed in 20% of the time. It is calculated using the following formula:
BHCA=(total calls * 0.5) / 1.6
Performance testing simulated busy hour by running VoIP and other peer-to-peer sessions at a busy hour load for at least 1.6 hours per day.
Conferencing peak load assumes that 75% of all conferences for an eight-hour day happen in 4 peak time hours. Those peak hours have 1.5 times the average conferencing load.