Cisco Systems OL-8155-01 Security Camera User Manual


 
Glossary
GL-12
Cisco IPICS Server Installation Guide
OL-8155-01
packet switching
The process of routing and transferring data by using addressed packets so that
a channel is occupied during the transmission of the packet only. Upon
completion of the transmission, the channel is made available for the transfer of
other traffic.
PIM
Protocol Independent Multicast. Multicast routing architecture that allows the
addition of IP multicast routing on existing IP networks. PIM is unicast routing
protocol independent and can be operated in two modes: PIM dense mode and
PIM sparse mode.
PIM dense mode
One of the two PIM operational modes. PIM dense mode is data-driven and
resembles typical multicast routing protocols. Packets are forwarded on all
outgoing interfaces until pruning and truncation occurs. In dense mode,
receivers are densely populated, and it is assumed that the downstream networks
want to receive and will probably use the datagrams that are forwarded to them.
The cost of using dense mode is its default flooding behavior. Sometimes called
dense mode PIM or PIM DM.
PIM sparse mode
One of the two PIM operational modes. PIM sparse mode tries to constrain data
distribution so that a minimal number of routers in the network receive it.
Packets are sent only if they are explicitly requested at the RP (rendezvous
point). In sparse mode, receivers are widely distributed, and the assumption is
that downstream networks will not necessarily use the datagrams that are sent to
them. The cost of using sparse mode is its reliance on the periodic refreshing of
explicit join messages and its need for RPs. Sometimes called sparse mode PIM
or PIM SM.
PMC
Push-to-Talk Management Center. A standalone PC-based software application
that simulates a handheld radio to enable PTT functionality for PC users. This
application enables Cisco IPICS PMC end-users, dispatch personnel, and
administrators to participate in one or more VTGs at the same time.
PMC ID
The unique ID that the Cisco IPICS server generates for each PMC to track
requests between the PMC and the server and to verify and manage concurrent
PMC usage for licensing requirements.
policy
An association of events or triggers to an action. Policies can include a set
sequence of actions, such as activating VTGs.