Spectralink 84-Series Series Wireless Telephones Administration Guide
1725-86984-000_P.docx
September 2016
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Primary server
The primary server is the highest priority server in a group of servers with an
active registration. All communications route to the primary server first, unless the handset
environment is configured otherwise.
Secondary server
A secondary server backs up a primary server when the primary server
fails. A secondary server may offer the same, or lesser, functionality than the primary server.
Server redundancy
This refers to the practice of employing multiple servers so that when a
primary server fails, a secondary server can take over.
Failover
A type of server redundancy in which a secondary server takes over all the functions
of the primary server when the primary server fails. No handset functionality is lost when the
secondary server takes over.
Fallback
In this mode, a second call server of lesser capability (such as a router or gateway
device) takes over call control to provide basic calling capability without some of the richer
features offered by the primary call server (for example, voicemail, presence, and Message
Waiting Indicator). Spectralink 84-Series handsets support configuration of multiple servers per
SIP registration for this purpose.
Re-registration on failover
A redundancy requirement in which a handset must successfully
register with a server before communications can take place. If a server fails and a handset
must communicate with another server (for example, a secondary server), the handset must
register with the secondary server before communications can take place.
Failback
A type of server redundancy in which a secondary server remains operational while
communications with a primary server are retried to see if the primary server is functioning
again. In certain configurations, the handset attempts to re-register with the primary server
during failback.
Register transaction
A register transaction associates a handset with a particular location,
such as an IP address. A handset sends a message
—called a ‘REGISTER’ message—
informing the server of its location.
Registrar or Registrar server
A registrar server accepts registrations, or location
information, from handsets and places this information in a database. Every handset must
register its current location with a Registrar server before the handset can communicate with a
server.
About the Optional Failover Behaviors
Spectralink handsets rely on two server redundancy technologies: failover and fallback. Using
these technologies, multiple servers are set up so that when the primary server fails, a
secondary server can take over. In some cases, a combination of the two may be deployed.
Consult your SIP server provider for recommended methods of configuring handsets and
servers for failover configuration.
Re-register on failover only applies to servers that use the failover method.