Networking Chapter 9

DSL modem

AKA DSL router it produces Ethernet 100 Base-T packets so it can be connected directly into a computer or to a router and hub and can serve the devices into one device so customers just have to install one box.

ARDNOC

Advanced Research and Development Network Operations Center - which develop CAnet (canadian project on the future internet)

ADSL

Asymmetric DSL- a data link layer technology that provides high speed communication over traditional telephone lines. A DSL modem is used to provide three channels; a traditional voice channel for communication from the client to the ISP and a downstream channel for communicating from the ISP to the client .

CPE

Customer premises equipment - equipment that provides the interface between the customers CENTREX system and the telephone network. It physically resides at the customer's site rather than the telephone companies end office. Generally refers to voice telephone equipment instead of data transmission equipment.

DSLAM

DSL access multiplexer- demultiplexes the data steams and converts them into ATM data, which are then distributed to the ISPs.

Broadband technologies

DSL and modem technologies since they provide higher speed communications than traditional modems.

DOCSIS

Data over Cable Services Interface Specifications - not a formal standard but it is one used by most vendors of Hybrid fiber coax (HFC) networks.

DSL

Digital subscriber line - a family of point to point technologies designed to provide high speed data transmission over traditional telephone lines.

FTTH

Fiber to the Home - runoff fiber optic cable into the home.

IAB

Internet Architecture Board - provides strategic architectural oversight. attempts to develop conclusions on strategic issues that can be passes on as guidance to the IESG or turned into published statements or simply passed directly to the relevant IETF working group.

IESG

Internet Engineering Steering Group - responsible for technical management of IETF activities and the internet standards process.

IETF

Internet Engineering Task Force - a large open international community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet Architecture and the smooth operation of the Internet.

IXPs

Internet Exchange Points- often run by a not for profit cooperative organization, permits any ISP to connect to its network

IRTF

Internet Research Task Force - operated much like the ITF through small research groups focused on specific issues.

ISP

Internet Service Provider - such as AT&T and sprint , that are responsible for large Internet networks.

ISOC

Internet Society - an open membership professional society with more than 175 organizational and 8000 individuals in over 100 countries, including corporations, government agencies, and foundations that have created the internet and its technologies.

MDF

Main distribution facility - works like CPE line splitter; it splits the voice traffic from the data traffic and directs the voice traffic to the voice telephone network and the data traffic to the DSL access multiplexer (DSLAM)

MAE

Metropolitan Area Exchange - smaller versions of NAPs and typically link a set of regional ISPs whose networks come together in major cities.

NAPS

Network Access Point - an intersection on the internet where many national and regional ISPs connect to exchange data.

NGI

Next generation Internet -

OE

Optical electrical converter - converts between the coaxial cable on the customer side and fiber optic cable in the cable TV company side.

ONU/ONT

Optical unit network/ optical network terminal - acts like DSL modem or cable modem and converts the signals in the optical network into an Ethernet format.

POP

Point of Presence - the place at which the ISP provides services to its customers. To connect to the internet a customer must establish a circuit from his or her location into the ISP POP.

RAS

Remote access Server - checks to make sure the user is a valid customer.

RFC

Request for Comment - form the basis for Internet standards are developed by the IETF and its working groups.

How the internet works?

The internet is a set of separate networks ranging from large national ISPs to midsize regional ISPs to small local ISPs that connect with one another at NAPs and MAEs. NAPs and MAEs charge the ISPs to connect, but similar sized ISP usually do not charge each other to exchange data. Each ISP has a set of points of presence through which it charges its users to connect to the Internet. Users connect to the POP to get access to the internet. This connection may be via a dial up modem over telephone line or via a high speed circuit such as DSL cable modem or a T1

UCAID

University Corporatioon for Advanced Internet Development- developed the Abeline network commonly called Internet2.

WiMAX

Worldwide Interoperability for Microwave Access - commercial name for a setoff standards developed by the IEEE 802.16 standards group.

Peering

a natinal tier 1 ISP does not charge another national tier 1 ISP to transmit its message. It is peering that makes the Internet work and has led to the belief that the internet is free.

National ISPs aka Tier 1 ISP

connect together and exchange data at Network Access Points (NAPS)

CMTS

contains a series of cable modems and converts the data from cable modem protocols into protocols needed for Internet traffic before passing them to a router to connect to an ISP POP

cable modem

digital service offered by cable television companies

Autonomous Systems

each ISP is responsible for running its own interior routing protocols and for exchanging routing information via the Border Gateway Protocol (BGP) exterior routing protocol.

Gigapops

each of the networks has a set of gigapops. They provide a point of presence at gigabit speeds.

How DSL works?

enables users to connect to an ISP POP over a standard point to point telephone line. The customer installs a DSL modem that connects via Ethernet to his or her computer system. The modem communities with a DSLAM at the telephone company office which sends the data to the ISP POP. ADSL is the most common type of DSL and provides 1.5Mbps downstream and 384Kbps upstream.

Local loop

part of communication circuit between the subscribers equipment in the local central office.

How does Cable Modem work

use a share multipoint circuit that runs through the cable TV cable. They also provide the customer with a modem that connects via Ethernet to his or her computer system. The modem communicates with a CMTS at the cable company office which sends the data to the ISP POP. The DOCSIS standard is the dominant standard but there are no standard data rates today.

line splitter

used to separate the traditional voice telephone transmission from the data transmission