Cisco 10000 Series Configuration Manual page 826

Glossary
random early
An alternative mechanism for avoiding congestion of Layer 3 queues. Random early detection (RED)
detection
implements a proactive queuing strategy that manages congestion before a queue reaches its queue
depth or limit.
Routing Information Protocol. An IGP used to exchange routing information within an autonomous
RIP
system, RIP uses hop count as a routing metric.
The path that network traffic takes from its source to its destination. The route a datagram follows can
route
include many gateways and many physical networks. In the Internet, each datagram is routed
separately.
A system responsible for making decisions about which of several paths network (or Internet) traffic
router
will follow. To do this, it uses a routing protocol to gain information about the network and algorithms
to choose the best route based on several criteria known as "routing metrics."
Information stored within a router that contains network path and status information. It is used to select
routing table
the most appropriate route to forward information along.
S
See sustainable cell rate.
SCR
Parameter defined by the ATM Forum for ATM traffic management. For VBR connnections, SCR
sustainable cell rate
determines the long-term average cell rate that can be transmitted.
See switched virtual circuit.
SVC
A virtual circuit that is dynamically established on demand and is torn down when transmission is
switched virtual
circuit complete. SVCs are used in situations where data transmission is sporadic. Called a switched virtual
connection in ATM terminology.
T
The default congestion avoidance mechanism for Layer 3 queues. Tail drop activates when a queue
tail drop
becomes full. After being activated, no packets make it to the queue. Tail drop treats all traffic equally
and does not differentiate between classes of service.
A QoS model that defines policies at three levels of hierarchy. See also hierarchical policies.
three-level
hierarchical policy
An algorithm used o manage the maximum rate of traffic. This algorithm defines the maximum rate of
token bucket
traffic allowed on an interface at a given moment in time. The token bucket algorithm is especially
useful in managing network bandwidth in cases where several large packets are sent in the same traffic
stream. The algorithm puts tokens into the bucket at a certain rate. Each token is permission for the
source to send a specific number of bits into the network.
Type of service. First defined in RFC 791.
ToS
Cisco 10000 Series Router Quality of Service Configuration Guide
GL-8
OL-7433-09