In an SMB Network, every computer is a potential master browser. This offers a level of redundancy as any computer can step in as the local master browser if it should fail. To determine which computer is the local master browser, an elections is held. An election can be forced by any computer, such as when a client needs the services of a browser but one is not available, or when a preferred master browser is booted onto the network.
In an election, a broadcast request is sent out causing all potential master browsers to respond identifying their OS Level. The highest OS Level wins the election and becomes the new master browser. In the event that two machines have the same OS Level, the winner is determined by which one is the Preferred Master Browser. If this does not break the tie, the winner is chosen by which machine has the greatest uptime. If that fails to break the tie, the winner is chosen by which comes first alphabetically.
The OS Level is defined for different Operating Systems below:
| Operating System | OS Level |
| Windows NT Server 4 | 33 |
| Windows NT Server 3.5 | 32 |
| Windows NT Workstation 4 | 17 |
| Windows NT Workstation 3.5 | 16 |
| Windows 98 | 2 |
| Windows 95 | 1 |
| Windows for Workgroups (3.1) | 1 |
Samba can be configured to use any OS level between 0 and 255. Samba can also be configured to be a Preferred Master Browser. You should not have more than one Preferred Master Browser in a Workgroup, as if one should lose an election, it will periodically force a new one causing excess network traffic.