Cisco Systems RJ-45-to-AUX manual 374

then forwards the frame out all the ports. American National Standards Institute (ANSI)

The organization that publishes standards for communications, programming languages, and networking.

ANDing

The process of comparing the bits of an IP address with the bits in a subnet mask to determine how a packet will be handled.

anycast address

An address used in ATM for shared multiple−end systems. An anycast address allows a frame to be sent to specific groups of hosts.

Application layer

The layer of the OSI model that provides support for end users and for application programs using network resources.

Application−Specific Integrated Circuit (ASIC)

A feature of many LAN controllers. ASICs are internal to the switch. They work in conjunction with the internal processor to make Layer 2 forwarding decisions. However, they lack the ability to make flexible software−implemented forwarding decisions. Their ability to perform small tasks quickly and inexpensively makes them a key in the switching process. ASICs used in Cisco switches and routers are the Phoenix, FE, LMA, PFPA, SAMBA, SAGE, SAINT, and CEF.

Asymmetric Digital Subscriber Line (ADSL)

A service that transmits digital voice and data over existing (analog) phone lines. Asynchronous Transfer Mode (ATM)

An international standard originally developed by the International Telecommunications Union Telecommunication Standardization Sector (ITU−T), used in high−speed transmission media such as E3, Synchronous Optical Network (SONET), and T3 for cell relay. It can be used in multiple service types such as voice, video, or data, and it’s sent in fixed−length, 53−byte cells. ATM has become common on today’s corporate networks. It guarantees throughput and minimizes delay. It can provide scalable speeds up to multiple gigabits per second.

Asynchronous Transmission Synchronization (ATS)

A process used in serial data transfer in which a start bit and a stop bit are added so the receiving station knows when a particular bit has been transferred. Also known as bit synchronization.

ATM Adaptation layer (AAL)

The ATM layer that adapts data to the ATM 48−byte payload. There are a number of adaptations to this layer, such as AAL1, AAL2, AAL3/4, and AAL5. AAL5 is by far the most common in today’s networks. AAL5 defines how data from a node on the network such as a PC or server handles ATM cells. It is also used by Cisco Catalyst switches with LANE to perform segmentation and reassembly of ATM frames into cells and cells into frames.

ATM System Processor (ASP)

A Cisco ATM cell−switching processing card, located on the Cisco Catalyst 5500 chassis or slot 2 on the LS1010 chassis.

attachment unit interface (AUI)

IEEE 802.3 specification used between a Multistation Access Unit (MAU) and a NIC. attachment unit interface (AUI) connector

A 15−pin D−type connector sometimes used with Ethernet connections. attenuation

The loss of signal that is experienced as data is transmitted across network media. Automated Packet Recognition and Translation (APaRT)

A FDDI line module feature found on Cisco Catalyst 2820 and 5000 series switches that allows for the automatic detection of frame types with translational bridging. It uses the CAM table to get the frame−type information for all end nodes.

374