Cisco Cisco IOS Software Release 12.2(18)S
MPLS Traffic Engineering – DiffServ Aware (DS-TE)
Glossary
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Cisco IOS Release 12.2(18)S
Glossary
CBR—Constraint Based Routing. The computation of traffic paths that simultaneously satisfy
label-switched path attributes and current network resource limitations.
label-switched path attributes and current network resource limitations.
CEF—Cisco Express Forwarding. A means for accelerating the forwarding of packets within a router, by
storing route lookup information in several data structures instead of in a route cache.
storing route lookup information in several data structures instead of in a route cache.
CLI—Command Line Interface. Cisco’s interface for configuring and managing its routers.
DS-TE—Diff Serv-aware Traffic Engineering. The capability to configure two bandwidth pools on each
link, a global pool and a sub-pool. MPLS traffic engineering tunnels using the sub-pool bandwidth can
be configured with Quality of Service mechanisms to deliver guaranteed bandwidth services end-to-end
across the network. Simultaneously, tunnels using the global pool can convey DiffServ traffic.
link, a global pool and a sub-pool. MPLS traffic engineering tunnels using the sub-pool bandwidth can
be configured with Quality of Service mechanisms to deliver guaranteed bandwidth services end-to-end
across the network. Simultaneously, tunnels using the global pool can convey DiffServ traffic.
flooding—A traffic passing technique used by switches and bridges in which traffic received on an
interface is sent out through all of the interfaces of that device except the interface on which the
information was originally received.
interface is sent out through all of the interfaces of that device except the interface on which the
information was originally received.
GB queue—Guaranteed Bandwidth queue. A per-hop behavior (PHB) used exclusively by the strict
guarantee traffic. If delay/jitter guarantees are sought, the diffserv Expedited Forwarding queue
(EF PHB) is used. If only bandwidth guarantees are sought, the diffserv Assured Forwarding PHB
(AF PHB) is used.
guarantee traffic. If delay/jitter guarantees are sought, the diffserv Expedited Forwarding queue
(EF PHB) is used. If only bandwidth guarantees are sought, the diffserv Assured Forwarding PHB
(AF PHB) is used.
Global Pool—The total bandwidth allocated to an MPLS traffic engineering link.
IGP—Interior Gateway Protocol. An internet protocol used to exchange routing information within an
autonomous system. Examples of common internet IGPs include IGRP, OSPF, and RIP.
autonomous system. Examples of common internet IGPs include IGRP, OSPF, and RIP.
label-switched path (LSP) tunnel—A configured connection between two routers, using label
switching to carry the packets.
switching to carry the packets.
LCAC—Link-level (per-hop) call admission control.
LSP—Label-switched path (see above).
Also Link-state packet—A broadcast packet used by link-state protocols that contains information about
neighbors and path costs. LSPs are used by the receiving routers to maintain their routing tables. Also called
link-state advertisement (LSA).
Also Link-state packet—A broadcast packet used by link-state protocols that contains information about
neighbors and path costs. LSPs are used by the receiving routers to maintain their routing tables. Also called
link-state advertisement (LSA).
MPLS—Multi-Protocol Label Switching (formerly known as Tag Switching). A method for directing
packets primarily through Layer 2 switching rather than Layer 3 routing, by assigning the packets short
fixed-length labels at the ingress to an MPLS cloud, using the concept of forwarding equivalence classes.
Within the MPLS domain, the labels are used to make forwarding decisions mostly without recourse to the
original packet headers.
packets primarily through Layer 2 switching rather than Layer 3 routing, by assigning the packets short
fixed-length labels at the ingress to an MPLS cloud, using the concept of forwarding equivalence classes.
Within the MPLS domain, the labels are used to make forwarding decisions mostly without recourse to the
original packet headers.
MPLS TE—MPLS Traffic Engineering (formerly known as “RRR” or Resource Reservation Routing). The
use of label switching to improve traffic performance along with an efficient use of network resources.
use of label switching to improve traffic performance along with an efficient use of network resources.
OSPF—Open Shortest Path First. A link-state, hierarchical IGP routing algorithm, derived from the IS-IS
protocol. OSPF features include least-cost routing, multipath routing, and load balancing.
protocol. OSPF features include least-cost routing, multipath routing, and load balancing.
RSVP—Resource reSerVation Protocol. An IETF protocol used for signaling requests (to set aside
internet services) by a customer before that customer is permitted to transmit data over that portion of
the network.
internet services) by a customer before that customer is permitted to transmit data over that portion of
the network.
Sub-pool—The more restrictive bandwidth in an MPLS traffic engineering link. The sub-pool is a
portion of the link’s overall global pool bandwidth.
portion of the link’s overall global pool bandwidth.
TE—Traffic engineering. The application of scientific principles and technology to measure, model, and
control internet traffic in order to simultaneously optimize traffic performance and network resource
utilization.
control internet traffic in order to simultaneously optimize traffic performance and network resource
utilization.