Cisco NM-8B-U - HW ROUTERS L-M User Manual page 244

16- and 36-Port Ethernet Switch Module for Cisco 2600 Series, Cisco 3600 Series, and Cisco 3700 Series
Glossary
QoS—quality of service. Measure of performance for a transmission system that reflects its transmission
quality and service availability.
RADIUS—Remote Access Dial-In User Service. A service used to authenticate and authorize clients.
RMON—remote monitoring. MIB agent specification described in RFC 1271 that defines functions for
the remote monitoring of networked devices. The RMON specification provides numerous monitoring,
problem detection, and reporting capabilities.
RSVP—Resource Reservation Protocol. Protocol that supports the reservation of resources across an IP
network. Applications running on IP end systems can use RSVP to indicate to other nodes the nature
(bandwidth, jitter, maximum burst, and so on) of the packet streams they want to receive. RSVP depends
on IPv6. Also known as Resource Reservation Setup Protocol.
SIP—Session Initiation Protocol. Protocol developed by the IETF MMUSIC Working Group as an
alternative to H.323. SIP features are compliant with IETF RFC 2543, which was published in March
1999. SIP equips platforms to signal the setup of voice and multimedia calls over IP networks.
SNMP—Simple Network Management Protocol. Network management protocol used almost
exclusively in TCP/IP networks. SNMP provides a means to monitor and control network devices and to
manage configurations, statistics collection, performance, and security.
stacking—Connecting two switches so they behave as one entity for management purposes. Regarding
an Ethernet switch network module, stacking means connecting two Ethernet switch network modules
inside a chassis so that they behave as one switch.
STP—Spanning Tree Protocol. Bridge protocol that uses the spanning-tree algorithm, which enables a
learning bridge to dynamically work around loops in a network topology by creating a spanning tree.
Bridges exchange BPDU messages with other bridges to detect loops and then remove the loops by
shutting down selected bridge interfaces. Refers to both the IEEE 802.1 Spanning-Tree Protocol
standard and the earlier Digital Equipment Corporation Spanning-Tree Protocol upon which it is based.
The IEEE version supports bridge domains and allows the bridge to construct a loop-free topology across
an extended LAN. The IEEE version generally is preferred over the Digital version.
supplicant—Entity requesting access to the network via the authenticator.
SVI—Switch Virtual Interface. Represents a VLAN of switch ports as one interface to the routing or
bridging function in a system.
VBR—variable bit rate. QoS class defined by the ATM Forum for ATM networks. VBR is subdivided
into a real time (RT) class and non-real time (NRT) class. VBR (RT) is used for connections in which
there is a fixed timing relationship between samples. VBR (NRT) is used for connections in which there
is no fixed timing relationship between samples but that still need a guaranteed QoS. Compare with
ABR, CBR, and UBR.
VLAN—virtual LAN. Group of devices on one or more LANs that are configured (using management
software) so that they can communicate as if they were attached to the same wire, when in fact they are
on separate LAN segments. Because VLANs are based on logical instead of physical connections, they
are extremely flexible.
VoIP—Voice over IP. Ability to carry normal telephony-style voice over an IP-based internet with
POTS-like functionality, reliability, and voice quality. VoIP enables a router to carry voice traffic (such
as telephone calls and faxes) over an IP network. In VoIP, the DSP segments the voice signal into frames,
which then are coupled in groups of two and stored in voice packets. These voice packets are transported
using IP in compliance with ITU-T specification H.323.
VoIPoFR—Voice-over-IP over Frame-Relay.
VPN—Virtual Private Network. Enables IP traffic to travel securely over a public TCP/IP network by
encrypting all traffic from one network to another. A VPN uses "tunneling" to encrypt all information at
the IP level.
Cisco IOS Release 12.2(2)XT, 12.2(8)T, and 12.2(15)ZJ
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