Nortel Ethernet Routing Switch 8600 Terminology Release: 5.0 Document Revision: 01.01 www.nortel.com NN46205-102 .
Nortel Ethernet Routing Switch 8600 Release: 5.0 Publication: NN46205-102 Document status: Standard Document release date: 30 May 2008 Copyright © 2008 Nortel Networks All Rights Reserved. Printed in Canada and the United States of America LEGAL NOTICE While the information in this document is believed to be accurate and reliable, except as otherwise expressly agreed to in writing NORTEL PROVIDES THIS DOCUMENT "AS IS" WITHOUT WARRANTY OR CONDITION OF ANY KIND, EITHER EXPRESS OR IMPLIED.
. Contents Software license 5 New in this release 9 Other changes 9 Terminology 9 Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
Introduction 11 A 13 B 17 C 21 D 25 E 29 F 31 G 33 H 35 I 37 J 41 L 43 M 47 N 53 O 55 P 57 Q 63 R 65 S 71 T 77 U 81 V 83 W 85 Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. Software license This section contains the Nortel Networks software license. Nortel Networks Inc. software license agreement This Software License Agreement ("License Agreement") is between you, the end-user ("Customer") and Nortel Networks Corporation and its subsidiaries and affiliates ("Nortel Networks"). PLEASE READ THE FOLLOWING CAREFULLY. YOU MUST ACCEPT THESE LICENSE TERMS IN ORDER TO DOWNLOAD AND/OR USE THE SOFTWARE. USE OF THE SOFTWARE CONSTITUTES YOUR ACCEPTANCE OF THIS LICENSE AGREEMENT.
Software license of this Agreement. Customer shall not a) use, copy, modify, transfer or distribute the Software except as expressly authorized; b) reverse assemble, reverse compile, reverse engineer or otherwise translate the Software; c) create derivative works or modifications unless expressly authorized; or d) sublicense, rent or lease the Software. Licensors of intellectual property to Nortel Networks are beneficiaries of this provision.
Nortel Networks Inc. software license agreement 7 software documentation and, in the event Software is licensed for or on behalf of the United States Government, the respective rights to the software and software documentation are governed by Nortel Networks standard commercial license in accordance with U.S. Federal Regulations at 48 C.F.R. Sections 12.212 (for non-DoD entities) and 48 C.F.R. 227.7202 (for DoD entities). 2. Customer may terminate the license at any time.
Software license Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. New in this release The following section details what’s new in Nortel Ethernet Routing Switch 8600 Terminology, NN46205-102 for Release 5.0: • “Other changes” (page 9) Other changes For information about changes that are not feature-related, see the following sections: Terminology Nortel Ethernet Routing Switch 8600 Terminology, NN46205-102 is a new document for Release 5.0. This document consolidates all terminology and acronyms into one document.
New in this release Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. Introduction This document provides information about the terms and acronyms used in the Nortel Ethernet Routing Switch 8600 documentation.
Introduction • • “V” (page 83) “W” (page 85) Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. A access control entry (ACE) One of the filter rules that comprise an access control list (ACL). A filter rule statement defines a pattern (in a packet) and the desired behavior for packets that carry the pattern. When the packets match an ACE rule, the specified action executes. access control list (ACL) An ordered list of filter rules referred to as access control entries.
A address resolution unit (ARU) An application specific integrated circuit (ASIC) that makes forwarding decisions that do not require CPU activity and, therefore; does not adversely affect forwarding speed. Advanced Encryption Standard (AES) A privacy protocol. AES is the current encryption standard (FIPS-197) intended for use by U.S. government organizations to protect sensitive information. aggregate A prefix length that is formed by combining several specific prefixes.
Navigation 15 attenuation The decrease in signal strength in an optical fiber caused by absorption and scattering. attribute A unit of data that is used by BGP to describe any of the following prefixes: AS-PATH, LOCAL-PREF, NEXT-HOP, and so on. automatic protection switching (APS) A Synchronous Optical Network (SONET) feature that protects against line failure.
A Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. B backplane forwarding module (BFM) Connects the switching module on the Web Switching Module (WSM) and SSL Acceleration Module (SAM) to the Nortel Ethernet Routing Switch 8600 backplane. backup designated router (BDR) Assumes the designated router (DR) role for the Open Shortest Path First (OSPF) protocol if the DR fails. bandwidth A measure of transmission capacity for a particular pathway, expressed in megabits per second (Mbit/s).
B bit error rate (BER) The ratio of the number of bit errors to the total number of bits transmitted in a given time interval. BGP (Border Gateway Protocol) An inter-domain routing protocol that provides loop-free inter-domain routing between autonomous systems (ASs) or within an AS. BGP neighbor BGP routers that have interfaces to a common network.
Navigation 19 bootstrap router (BSR) A dynamically elected Protocol Independent Multicast (PIM) router that collects information about potential Rendezvous Point routers and distributes the information to all PIM routers in the domain. Border Gateway Protocol (BGP) An exterior gateway protocol that routers use in different autonomous systems (AS) to exchange routing information. boundary port A bridge port that attaches a Multiple Spanning Tree (MST) bridge to a LAN in another region.
B Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. C cable assembly An optical-fiber cable with connectors installed on one or both ends. The cable assembly interconnects the cabling system with opto-electronic equipment at either end of the system. Cable assemblies with connectors only on one end are called pigtails. Cable assemblies with connectors on both ends are called jumpers or patch cords. cable plant All the optical elements, such as fiber connectors and splices, between a transmitter and a receiver.
C Circuitless IP A virtual interface that does not map to any physical interface. This interface is often called a loopback. class of service (CoS) A method used to manage traffic congestion based on the CoS level assigned to the packet. classless interdomain routing (CIDR) The protocol defined in RFCs 1517 and 1518 for using subnetwork masks, other than the defaults for IP address classes.
Navigation 23 community A BGP attribute that contains a list of 32-bit values used to identify a route as belonging to a category of routes. All of the routes in the category are treated equally by routing policies. constant bit rate (CBR) A data service that conveys bits regularly in time and at a constant rate, between source (transmitter) and sink (receiver), for example, follows a timing source or clock. Custom AutoNegotiation Advertisement (CANA) An enhancement of the IEEE 802.
C Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. D Data Encryption Standard (DES) A cryptographic algorithm that protects unclassified computer data. The National Institute of Standards and Technology publishes the DES in the Federal Information Processing Standard Publication 46-1. Data Communications Equipment (DCE) A network device (such as a modem) that establishes, maintains, and terminates a session. Data Terminating Equipment (DTE) A computer or terminal on the network that is the source or destination of signals.
D dense wavelength division multiplexing (DWDM) A technology that uses many optical signals (16 or more) with different wavelengths to simultaneously transmit in the same direction across one fiber, and then separates by wavelength at the distant end. demultiplexing The wavelength separation in a wavelengthdivision multiplexing system. The opposite of multiplexing. designated router (DR) A single router elected as the designated router for the network.
Navigation 27 Differentiated Services Code Point (DSCP) The first six bits of the DS field. The DSCP uses packet marking to guarantee a fixed percentage of total bandwidth to each of several applications (guarantees Quality of Service).
D Distributed MultiLink Trunking (DMLT) A point-to-point connection that aggregates similar ports from different modules to logically act like a single port, but with the aggregated bandwidth. distribution tree A set of multicast routers and subnetworks that allow the group members to receive traffic from a source. Domain Name System (DNS) A system that maps and converts domain and host names to IP addresses. downstream node Refers to the node that the packet enters on the downstream node.
. E Electromagnetic Interference (EMI) Electromagnetic radiation released from an electronic device that disrupts the operation or performance of another device. Electrostatic Discharge (ESD) The discharge of stored static electricity that can damage electronic equipment and impair electrical circuitry that results in complete or intermittent failures. emulated LAN (ELAN) A virtual LAN (VLAN) for Asynchronous Transfer Mode (ATM).
E explicit route (ER) Defines one or more hops in the label switched path (LSP) in a Multiprotocol Label Switching (MPLS) network. explicit path A Resource Reservation Protocol (RSVP) hop-by hop tunnel that terminates on an interface IP address on the egress Label Edge Router (LER). Extended Unique Identifier (EUI) A 64-bit format used in assigning addresses automatically to IPv6 interfaces. Extensible Authentication Protocol over LAN (EAPoL) A port-based network access control protocol.
. F far end fault indication (FEFI) Determines that one of two unidirectional fibers, that form the connection between two switches, fails. Feedback Output Queue (FOQ) A mechanism that helps the Nortel Ethernet Routing Switch 8600 avoid switch fabric congestion. FEC to NHLFE table (FTN) A lookup table that is consulted for incoming, unlabeled packets to determine which label values to use when encapsulating the packet. (See also Next Hop Label Forwarding Entry [NHLFE]).
F Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. G Generalized Regular Expression Parser (GREP) A Unix command used to search files for lines that match a given regular expression (RE). get nearest server (GNS) A request used by Internetwork Packet Exchange (IPX) clients to find a login server. gigabit Ethernet (GE) Ethernet technology with speeds up to 1 Gbit/s.
G Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. H High Availability (HA) Activates two CPUs simultaneously. The CPUs exchange topology data so, if a failure occurs, either CPU can take precedence in less than 1 second with the most recent topology data. Hypertext Transfer Protocol (HTTP) Communications protocol for the Web. Hypertext Transfer Protocol, Secure (HTTPS) Communications protocol used to access a secure Web server. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.
H Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. I incoming label map (ILM) An index used to map an incoming labeled packet to an NHLFE. Institute of Electrical and Electronics Engineers (IEEE) An international professional society that issues standards and is a member of the American National Standards Institute and the International Standards Institute, and the International Standards Organization. integrated service director (ISD) The processor PCI Mezzanine Card (PrPMC) and disk drive on a firewall module.
I Internet Assigned Numbers Authority (IANA) The central registry for various assigned numbers, for example, Internet protocol parameters (such as port, protocol, and enterprise numbers), options, codes, and types. Internet Control Message Protocol (ICMP) A collection of error conditions and control messages exchanged by IP modules in both hosts and gateways. Internet Engineering Task Force (IETF) A standards organization for IP data networks.
Navigation 39 Internet Protocol version 4 (IPv4) The protocol used to format packets for the Internet and many enterprise networks. IPv4 provides packet routing and reassembly. Internet Protocol version 6 (IPv6) An improved version of the IP protocol. IPv6 improves the IPv4 limitations of security and user address numbers. Internetwork Packet Exchange (IPX) A network layer protocol. IPX is similar to IP but does not guarantee packet delivery.
I Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. J jitter The delay variance between received packets. Packets may not arrive at the destination address in consecutive order, or on a timely basis, and the signal can vary from its original reference timing. This distortion damages multimedia traffic. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
J Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. L label A fixed length header that an LSR uses to forward packets along a Label Switched Path (LSP). A label represents a FEC. label binding An association between a label and a FEC, which can be advertised to neighbors to establish an LSP. label advertise mode This mode (downstream unsolicited or downstream on demand) determines when the interface distributes label mappings to the next hop upstream.
L label edge router (LER) Resides at the network edge to initiate and terminate label switched paths and assign packets to forward equivalence class (FEC) as traffic enters the Multiprotocol Label Switching (MPLS) network. label information base (LIB) A table of incoming labels, outgoing labels, and interface mappings.
Navigation 45 last member query interval (LMQI) The time between when the last IGMP member leaves the group and the stream stops. latency The time between when a node sends a message and receipt of the message by another node; also referred to as propagation delay. Layer 2 (L2) The Data Link Layer of the Open System Interconnection (OSI) model. Examples of Layer 2 protocols are Ethernet and Frame Relay. Layer 3 (L3) The Network Layer of the OSI model.
L link-state advertisement (LSA) Packets that contain state information about directly connected links (interfaces) and adjacencies. Each Open Shortest Path First (OSPF) router generates the packets. link-state database (LSDB) A database built by each OSPF router to store LSA information. The router uses the LSDB to calculate the shortest path to each destination in the autonomous system (AS), with itself at the root of each path.
. M management information base (MIB) Defines system operations and parameters used for the Simple Network Management Protocol (SNMP). marking A process that uses defined rules to assign the Differentiated Services Code Point (DSCP) in a packet. mask A bit string that is used along with an IP address to indicate the number of leading bits in the address that correspond with the network part.
M Media Access Control (MAC) Arbitrates access to and from a shared medium. media access unit (MAU) The equipment in a communications system that adapts or formats signals, such as optical signals, for transmission over the propagation medium. media dependent adapter (MDA) An independent module, that features an input or output port that interfaces to a media connector. Message Digest 5 (MD5) A one-way hash function that creates a message digest for digital signatures.
Navigation 49 multihomed AS An AS that has multiple connections to one or more ASs and does not carry transit traffic. Multicast Link Discovery (MLD) An asymmetric protocol. MLD specifies separate behaviors for multicast address listeners and multicast routers. multicast router discovery (MRDISC) Provides the automatic discovery of multicast capable routers.
M multiplexing Carriage of multiple channels over a single transmission medium; a process where a dedicated circuit is shared by multiple users. Typically, data streams intersperse on a bit or byte basis (time division), or separate by different carrier frequencies (frequency division). multiplexer (MUX) A device that combines two or more signals into a signal composite data stream for transmission on a single channel.
Navigation 51 Multiprotocol Label Switching (MPLS) A technique promoted by the Internet Engineering Task Force (IETF) that integrates the label-swapping paradigm with network-layer routing to flexibly provide high-speed services with quality-of-service guarantees over IP and ATM networks. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
M Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. N nanometer (nm) One billionth of a meter (109 meter). A unit of measure commonly used to express the wavelengths of light. neighbor discovery (ND) Used by IPv6 nodes (routers and hosts) on the same link to discover link layer addresses and obtain and advertise various network parameters and reachability information. Network Address Translation (NAT) Provides access to the Internet for network ports by using one or more globally unique IP addresses.
N network-to-network interface (NNI) An interface between two networks in different management domains. next hop The next hop to which a packet can be sent to advance the packet to the destination. Next Hop Label Forwarding Entry (NHLFE) n index used to forward a labeled packet. It contains the next hop of the packet and instructions of what to do, either swap the label or pop the label stack.
. O Open Shortest Path First (OSPF) A link-state routing protocol used as an Interior Gateway Protocol (IGP). Open Systems Interconnection (OSI) A suite of communication protocols, network architectures, and network management standards produced by the International Organization for Standardization (ISO). OSI-compliant systems can communicate with other OSI-compliant systems for a meaningful exchange of information.
O Optical Carrier-level 3 concatenation (OC-3c/STM-1) An optical fiber transmission system that carries Synchronous Transport Signal (STS)-3c/Synchronous Transport Module (STM)-1 frame structures at 155 Mbit/s. Concatenation means only one logical data stream (rather than supporting a channelized structure) exists. Optical Carrier-level 12 concatenation (OC-12c/STM-4) An optical fiber transmission system that carries STS-12c/STM-4 frame structures at 622 Mbit/s.
. P Packet Capture Tool (PCAP) A data packet capture tool that captures ingress and egress (E-modules only) packets on selected I/O ports. You can analyze captured packets for troubleshooting purposes. packet loss Expressed as a percentage of packets dropped over a specified interval. Keep packet loss to a minimum to deliver effective IP telephony and IP video services.
P peak cell rate (PCR) The upper limit on the time interval between two consecutive ATM cell emissions. penultimate router Penultimate means next-to-last. In this case, it refers to the next-to-last provider router in the network. per-hop behavior (PHB) A traffic class forwarding treatment based on criteria defined in the DiffServ field. permanent virtual connection (PVC) An ATM channel connection or path connection configured at the network management interface.
Navigation 59 Point-to-Point Protocol (PPP) A network protocol used to dial into an Internet Service Provider (ISP). Serial Line Interface Protocol (SLIP) and PPP provide full Transmission Control Protocol/Internet Protocol (TCP/IP) capabilities to the casual dial-up user. policing Ensures that a traffic stream follows the domain service provisioning policy or service level agreement (SLA). port A physical interface that transmits and receives data.
P prefix A group of contiguous bits, from 0 to 32 bits in length, that defines a set of addresses. primary rate interface (PRI) An integrated service digital network (ISDN) interface standard designed in North America as having 23 circuit-switched B channels and one D channel, which operate at 64 kbit/s. private virtual circuit (PVC) An ATM channel connection or path connection configured at the network management interface.
Navigation 61 Protocol Independent Multicast, Sparse Mode (PIM-SM) Adds a Rendezvous Point router to avoid multicast-data flooding. Use PIM–SM when receivers for multicast data are sparsely distributed throughout the network. Protocol Independent Multicast, Split MultiLink Trunking (PIM-SMLT) Builds a virtual switch that represents the two switches of the split multilink trunk core.
P Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. Q quality of service (QoS) The collective effect of service performances that determine the degree of satisfaction of a service user. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
Q Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. R Random Access Memory (RAM) Memory into which you can write and read data. A solid state memory device used for transient memory stores. You can enter and retrieve information from any storage position. Rapid Spanning Tree Protocol (RSTP) Reduces the recovery time after a network breakdown. RSTP enhances switch-generated Topology Change Notification (TCN) packets to reduce network flooding. Read Write All (RWA) An access class that lets users access all menu items and editable fields.
R reduced instruction set computer (RISC) A computer that employs a small, simplified set of frequently used instructions for rapid execution. remarking Changes the Differentiated Services Code Point (DSCP) of a packet, in accordance with a service level agreement (SLA). Remote Authentication Dial-in User Service (RADIUS) A protocol that authenticates, authorizes, and accounts for remote access connections that use dial-up networking and virtual private network (VPN) functionality.
Navigation 67 remote monitoring (RMON) A remote monitoring standard for Simple Network Management Protocol (SNMP)-based management information bases (MIB). The Internetwork Engineering Task Force (IETF) proposed the RMON standard to provide guidelines for remote monitoring of individual LAN segments. rendezvous point (RP) The root of the shared tree. One RP exists for each multicast group.
R Report Route Object (RRO) A feature of the RSVP. It allows the path through the MPLS cloud to be displayed at the sender of the path if RRO is set to true. Resource Reservation Protocol-Traffic Engineering (RSVP-TE) A label signaling protocol that establishes traffic-engineered label switched paths (LSP) through the Multiprotocol Label Switching (MPLS) network.
Navigation 69 Remote Service Provider (RSP) Resource Reservation Protocol-Traffic Engineering (RSVP-TE) A protocol with traffic engineering extensions, which reserves network resources to establish explicitly routed MPLS tunnels. Routing Information Protocol (RIP) Distance-vector-based interior gateway routing protocol. Routing policy Any form of routing that is influenced by factors other than the default algorithmically best route, such as the shortest or quickest path.
R Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. S Source Address and Destination Address (SA/ DA) Secure Copy (SCP) Securely transfers files between the switch and a remote station. Secure Shell (SSH) Used for secure remote logons and data transfer over the Internet. SSH uses encryption to provide security. Secure Sockets Layer (SSL) An Internet security encryption and authentication protocol for secure point-to-point connections over the Internet and intranets, especially between clients and servers.
S shim MPLS uses a shim header for Ethernet packets so they can accommodate a label in their header. MPLS uses the shim to make forwarding decisions. The shim label is a 32-bit identifier used to identify a FEC. shortest path first (SPF) A class of routing protocols that use Djikstra’s algorithm to compute the shortest path through a network, according to specified metrics, for efficient transmission of packet data.
Navigation 73 SMLT aggregation switch Connects to multiple wiring closet switches, edge switches, or Customer Premise Equipment (CPE) devices. SMLT client A switch located at the edge of the network, such as in a wiring closet or CPE. An SMLT client switch performs link aggregation but does not require Split MultiLink Trunking (SMLT) intelligence.
S SSL Acceleration Module (SAM) Intelligently accelerates secure business transactions and confidential data by off-loading SSL processing from local servers without imposing delays on other traffic in the same data path. sustainable cell rate (SCR) The expected rate of cell transmission on a nonconstant bit rate (CBR) transmission. Switch Fabric (SF) In signal computing system architecture (SCSA), the facility that connects two (or more) transmitting or receiving service providers.
Navigation 75 National Standards Institute (ANSI) standard provides transmission from OC-1 to OC-48 and greater. System Administration, Networking and Security Institute (SANS) The research and education organization for network administrators and security professionals. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
S Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. T TCP (Transport Control Protocol) The main reliable transport protocol used in the Internet (and with BGP). transparent domain identifier (TDI) A User-to-Network Interface (UNI) port configured as transparent service type assigns all traffic to its associated transparent domain using the TDI. Transparent LAN Service (TLS) TLS is the component of the Nortel Networks OE solution that allows a group of customer sites to appear as one single LAN, regardless of their geographic location.
T traffic profile The temporal properties of a traffic stream, such as rate. transit AS An AS that has multiple connections to one or more ASs and is used (with certain policy restrictions) to carry both transit and local traffic. Transmission Control Protocol (TCP) Provides flow control and sequencing for transmitted data over an end-to-end connection. Transmission Control Protocol over IP (TCP/IP) A protocol stack designed to connect different networks.
Navigation 79 tunnel groups A collection of RSVP tunnels. Television (TV) A widely used telecommunication system for broadcasting and receiving moving pictures and sound over a distance. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
T Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
. U universal asynchronous receiver-transmitter (UART) A device that converts outgoing parallel data to serial transmission and incoming serial data to parallel for reception. Universal/Local (U/L) Determines global and local link addresses; used with the Extended Unique Identifier (EUI). universal resource locator (URL) A standardized method that represents different documents, media, and network services on the World Wide Web.
U User Datagram Protocol (UDP) In TCP/IP, a packet-level protocol built directly on the Internet Protocol layer. TCP/IP host systems use UDP for application-to-application programs. user-to-network interface (UNI) An interface between ATM user equipment and ATM network equipment. upstream node An upstream node refers to the node that the packet exits on its way to the downstream node on the next hop LSR. Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.
. V variable bit rate (VBR) The capability of the encoding algorithm to dynamically switch between 32 and 24 kbytes/s. view-based access control model (VACM) Provides context, group access, and group security levels based on a predefined subset of management information base (MIB) objects. virtual connection (VC) A communication channel that provides sequential unidirectional transport of Asynchronous Transfer Mode (ATM) cells among ATM layer entities.
V virtual private network identifier (VPN-ID) A globally significant VPN identifier. virtual router (VR) An abstract object managed by the Virtual Router Redundancy Protocol (VRRP) that acts as a default router for hosts on a shared LAN. virtual router forwarding (VRF) Provides traffic isolation between the customers operating over the same node.
. W wavelength division multiplexing (WDM) Simultaneously transmits many colors (wavelengths) of laser light down the same optical fiber to increase the amount of transferred information. Web Switching Module (WSM) Provides content-intelligent processing of Web-based traffic. weighted round robin (WRR) A mechanism that uses the packet transmit opportunity (PTO) of a queue to determine which queue to process first.
W Nortel Ethernet Routing Switch 8600 Terminology NN46205-102 01.01 Standard 30 May 2008 Copyright © 2008 Nortel Networks .
Nortel Ethernet Routing Switch 8600 Terminology Copyright © 2008 Nortel Networks All Rights Reserved. Printed in Canada and the United States of America Release: 5.0 Publication: NN46205-102 Document status: Standard Document revision: 01.01 Document release date: 30 May 2008 To provide feedback or to report a problem in this document, go to www.nortel.com/documentfeedback. www.nortel.
