Final: Chapter 10 The Internet

What are the four interrelated standards bodies of the Internet Society

1) Internet Engineering Task Force 2) Internet Engineering Steering Group 3) Internet Architecture Board 4) Internet Research Task Force.

The most common architecture for cable modems

1) The cable TV circuit enters the customer premises through a cable splitter that separates the data transmissions from the TV transmissions and sends the TV signals to the TV network and the data signals to the cable modem. 2) The cable modem (both a modem and frequency division multiplexer) translates from the cable data into Ethernet packets, which then are directed into a computer to a router for distribution in a small network.

How is fiber to home implemented?

1) The traditional set of hundreds of copper telephone lines that run from the telephone company switch office is replaced by one fiber-optic cable that is run past each house or office in the neighborhood. 2) Data are transmitted down the signal fiber cable using wavelength division multiplexing (WDM), providing hundreds or thousands of separate channels. FTTH is only available to about a quarter of the homes in the United States and Canada, but it is growing.

Most commonly used type of FTTH?

15 Mbps downstream and 4 Mbps upstream.

What frequency's does WiMax use?

2.3, 2.5, and 3.5 GHz frequency ranges in North America, although additional frequency ranges may be added.

The maximum range for WiMax is . . .

3 to 10 miles, depending on interference and obstacles between the device and the AP. Most WiMax providers in the United States are using effective ranges of 0.5-1.5 miles when they install WiMax APs.

autonomous system

A collection of IP networks and routers under the control of one administrative entity

Border Gateway Protocol (BGP)

A core routing protocol that bases routing decisions on the network path and rules.

Next Generation Internet (NGI)

A government project to develop new, faster technologies to enhance research and communication.

Internet2

A new, faster telecommunications network that deploys advanced network applications such as remote medical diagnosis, digital libraries, distance education, online simulation, and virtual laboratories.

examples of tier 1 ISPs

AT&T, Sprint, Verizon, Qwest, Level 3, and Global Crossing

distribution hub

Also known as a headend. Owned by a cable company and can connect to it through two separate circuits (upstream and downstream circuits).

What does ADSL stand for?

Asymmetric Digital Subscriber Line

How is FTTH similar to DSL?

At each subscriber location, an optical network unit (ONU) (also called an optical network terminal [ONT]) acts like a DSL modem or cable modem and converts the signals in the optical network into an Ethernet format. The ONU acts as an Ethernet switch and can also include a router. FTTH is a dedicated point-to-point service like DSL, not a shared multipoint service like cable modem.

Types of FTTH (Fiber to the Home)

Common types provide 10-100 Mbps downstream and 1-10 Mbps upstream

Difference between a cable modem architecture and DSL architecture

DSL is a point-to-point technology, whereas cable modems use shared multipoint circuits

To connect into the Internet, a customer must establish a circuit from his or her location into the ISP POP. For individuals, this is often done using a . . .

DSL modem or cable modem

request for comments (RFCs)

IETF standards documents that specify or describe best practices, provide information about the Internet, or specify an Internet protocol or service.

Internet exchange points (IXPs)

Nodes on the Internet where data from one service provider is transferred to a different service provider.

broadband technologies

Provide higher speed communications than traditional modems.

Today, the backbone circuits of the major U.S. national ISPs operate at . . .

SONET OC-192 (10 Gbps).

Internet Architecture Board (IAB)

The IAB appoints the IETF chair person and all IESG members, from a list provided by the IETF nominating committee. The IAB also adjudicates appeals when someone complains that the IESG has failed.

What is the closest thing the Internet has to an owner?

The Internet Society (internetsociety.org)

customer premises equipment (CPE)

The equipment at the customer site that's usually the responsibility of the customer.

local loop

The part of a phone system that `connects a customer site with a telecommunications carrier's switching facility.

What is the reason for limited capacity on traditional telephone circuits?

The switching equipment at the end offices

A typical segment of cable is shared by anywhere from 300 to 1,000 customers, depending on the cable company that installed the cable. True or False?

True

All of the giga pops provide connections at layer 1, the physical layer. Many of the giga pops also provide layer 2 connections (usually Ethernet) and layer 3 connections (usually IPv6). Typical connection fees range from$6,000 per year for 1 Gbps to $165,000 per year for 100 Gbps. True or False?

True

Downstream data traffic enters the distribution hub from the ISP POP and is routed through the CMTS, which produces the cable modem signals. This traffic is then sent to a combiner, which combines the Internet data traffic with the ordinary TV video traffic and sends it back to the fiber node for distribution. True or False?

True

In a cable modem architecture. If your neighbors were hackers, they could use pocket sniffers such as Wireshark (see Chapter 4) to read all messages that travel over the cable, including yours. True or False?

True

Local ISPs charge individuals for access, whereas national and regional ISPs (and sometimes local ISPs) charge larger organizations for access. True or False?

True

Providers of Fiber to the Home can use either active optical networking or passive optical networking to connect the ONU in the customers home. True or False?

True

The DSL Modem aka DSL Router is both a modem and a frequency division multiplexing (FDM) multiplexer. True or False?

True

The Internet exists only to the extent that these thousands of separate networks agree to use Internet protocols and to exchange data packets among one another. True or False?

True

The line splitter also directs the data transmissions into a DSL modem, which is sometimes called a DSL route. True or False?

True

The shorter the distance, the higher the speed, because with a shorter distance, the circuit suffers less attenuation and higher-frequency signals can be used, providing a greater bandwidth for modulation. True or False?

True

The size of the two digital channels depends on the distance from the CPE to the end office. True or False?

True

With cable modems, each user must compete with other users for the available capacity. Furthermore, because the cable circuit is a multipoint circuit, all messages on the circuit go to all computers on the circuit. True or False?

True

Who was the Internet primarily run by in in the 1990s?

US National Science Foundation (NSF)

Why are all IXPs non profit today?

When the NSF stopped funding the Internet, the companies running these IXPs began charging the ISPs for connections so today the IXPs in the United States are all not-for-profit organizations or commercial enterprises run by various common carriers such as AT&T and Sprint (266)

Digital subscriber line (DSL)

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

Internet Engineering Task Force (IETF)

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. The IETF works through a series of working groups, which are organized by topic (e.g., routing, transport, and security).

Internet

a network of networks—a set of separate and distinct networks operated by various national and state government agencies, nonprofit organizations, and for-profit corporations.

tier 3 ISPs

acquire Internet service from Tier 2 ISPs; focus of these ISPs is the retail and home networks in a specific locale; often bundle Internet connectivity as a part of network and computer service contracts for their customers; good choice for small to medium sized companies

The Internet Society

an open-membership professional society with about 150 organizational members and 65,000 individual members in more than 100 countries, including corporations, government agencies, and foundations that have created the Internet and its technologies. Because membership is open, anyone, including students, is welcome to join and vote on key issues facing the Internet.

What is the most common type of DSL?

asymmetric DSL (ADSL)

distributed denial-of-service attack (DDOS)

attacks from multiple computers that flood a website with so many requests for service that it slows down or crashes. A common type is the Ping of Death, in which thousands of computers try to access a website at the same time, overloading it and shutting it down.

Why is ADSL called asymmetric?

because its two data channels have different speeds. Each of the two data channels is further multiplexed using time division multiplexing so they can be subdivided

What is the problem with WiMax

computer manufacturers have been waiting for ISPs to build WiMax networks before they build WiMax into their computers. Meanwhile, ISPs have been waiting for computer manufacturers to provide WiMax-capable computers before they build WiMax networks.

cable modem termination system (CMTS)

contains a series of cable modems/multiplexers and converts the data from cable modem protocols into protocols needed for Internet traffic, before passing them to a router connected to an ISP POP. Often, the cable company is a regional ISP, but sometimes it just provides Internet access to a third-party ISP

DSL access multiplexer (DSLAM)

demultiplexes the data streams and converts them into digital data, which are then distributed to the ISPs. Some ISPs are collocated, in that they have their POPs physically in the telephone company end offices. Other ISPs have their POPs located elsewhere.

Passive optical networking devices require no . . .

electrical current and thus are quicker and easier to install and maintain than traditional electrical-based devices, but because they are passive, the optical signal fades quickly, giving a maximum range of about 10 miles.

What is The Internet Society mission?

ensure "the open development, evolution and use of the Internet for the benefit of all people throughout the world."

fiber node

has an optical-electrical (OE) converter to convert between the coaxial cable on the customer side and fiber-optic cable on the cable TV company side. Each fiber node serves as many as half a dozen separate coaxial cable runs

What is the 2nd Channel used when ADSL uses FDM?

is a relatively high-speed data channel downstream from the carrier's end office to the customer.

What is the 3rd Channel used when ADSL uses FDM?

is a slightly slower data channel upstream from the customer to the carrier's end office.

Internet Engineering Steering Group (IESG)

is responsible for technical management of IETF activities and the Internet standards process. It administers the process according to the rules and procedures that have been ratified by the Internet Society trustees. The IESG is directly responsible for the actions associated with entry into and movement along the Internet "standards track," including final approval of specifications as Internet standards. Each IETF working group is chaired by a member of the IESG.

In terms of public policy, the Internet Society participates in . . .

national and international debates on important issues such as censorship, copyright, privacy, and universal access.

What was the 1990s name for an IXP (Internet Exchange Points)?

network exchange point or NAP

Data over Cable Service Interface Specification (DOCSIS)

not a formal standard but is the one used by most vendors of hybrid fiber coax (HFC) networks (i.e., cable networks that use both fiber-optic and coaxial cable).

Internet Research Task Force (IRTF)

operate much like the IETF. Through small research groups focused on specific issues. IRTF research groups work on long-term issues related to Internet protocols, applications, architecture, and technology. The IRTF chairperson is appointed by the IAB.

The downstream circuit to the customer contains both . . . .

ordinary video transmissions from the cable TV video network and data transmissions from the Internet.

national ISPs

provide internet access in cities and towns nationwide

What are the three general areas of The Internet Society

public policy, education, and standards

Regional ISPs (Tier 2 ISPs)

rely on tier 1 ISPs to transmit their messages to ISPs in other countries

Why is DSL so attractive?

requires just changing the telephone equipment, not rewiring the local loop

Fiber to the home (FTTH)

running fiber-optic cable into the home

line splitter

s used to separate the traditional voice telephone transmission from the data transmissions. Also, it directs the telephone signals into the normal telephone system so that if the DSL equipment fails, voice communications are unaffected

Point of Presence (POP)

simply the place at which the ISP provides services to its customers.

WiMax (short for Worldwide Interoperability for Microwave Access)

the commercial name for a set of standards developed by the IEEE 802.16 standards group. WiMax is a family of technologies that is much like the 802.11 Wi-Fi family. It reuses many of the Wi-Fi components and was designed to connect easily into Ethernet LANs. WiMax can be used as a fixed wireless technology to connect a house or an office into the Internet, but its future lies in its ability to connect mobile laptops and smartphones into the Internet.

Active networking means

the optical devices require electrical power and works in much the same way as traditional electronic switches and routers.

What is the 1st Channel used when ADSL uses FDM?

the traditional voice telephone circuit

gigapops

they provide a POP at gigabit speeds.

What does ADSL use FDM for?

to create three separate channels over the one local loop circuit.

distributed denial-of-service attack (DDOS) software is most often contained in a . . .

video, a song, or a free application that the unsuspecting user has downloaded.

peering

when national tier 1 ISPs do not charge another national tier 1 ISP to transmit messages

Mobile WiMax

works in much the same way as Wi-Fi.The laptop or smartphone has a WiMax network interface card (NIC) and uses it to establish a connection to a WiMax access point (AP).

main distribution facility (MDF)

works similarly to the 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