NVCC ITN 100 EXAM 2

which application layer process the packet is from

The source destination port identifier tells the destination station _____________.

Connectionless

______________ routing is most commonly used when the application data or message can fit into one single packet.

True

Subnet masks tell computers what part of an IP address is to be used to determine whether a destination is in the same subnet or in a different subnet.

True or False

False

TCP/IP operates only as connection-oriented

True or False

False

The standard port number for Telnet is 53.

True or False

True

An Address Resolution Protocol message is broadcast to all computers in a subnet to find the data link layer address.

True or False

Multicast message

A special type of message that is used when sending the same message to a specific group of computers is called a:

Routing

___________ is the process of determining the path that a message will travel from sending computer to receiving computer.

False

There are four fundamental approaches to routing: centralized, static routing, dynamic routing, and monitor routing.

True or False

True

Because there is a limit on the length of a frame that the data link layer can transmit from node to node, the transport layer breaks up the message from the application layer into several smaller packets.

True or False

Ports

Used to identify application

Connection Oriented

Using a session to send data is called

Connectionless

Sending messages without establishing a session is

IP Address

129.79.78.193

Subnet Mask

255.255.255.0

Dynamic Host Configuration Protocol

What does DHCP stand for?

Domain Name Service

What does DNS stand for?

Address Resolution Protocol

What does ARP stand for?

Routing Tables

-Used to make routing decisions

-Shows which path to send packets on to reach a given destination

-Kept by computers making routing decisions

What is this?

Centralized Routing

-Routing decisions made by one computer

-Not common anymore

What is this?

Decentralized Routing

-Decisions made by each node independently of one another

-Information needs to be exchanged to prepare routing tables

-Used by the Internet

What is this?

Static

-Fixed routing tables

-Manually configured by network managers

-Local adjustments when computers added or removed

What is this?

Dynamic

-Routing tables updated periodically

-Routers exchange information using protocols to update tables

What is this?

Distance Vector

based on the number of "hops" between two devices

Link State

based on the number of hops, circuit speed, and traffic congestion

Routing Information Protocol (RIP)

Dynamic distance vector protocol used for interior routing

Open Shortest Path First (OSPF)

Dynamic link state protocol used for interior routing

Enhanced Interior Gateway Routing Protocol (EIGRP)

A dynamic link state protocol (developed by Cisco)

Border Gateway Protocol (BGP)

Dynamic distance vector protocol used for exterior routing

Unicast

one computer to another computer

Broadcast

one computer to all computers in the network

Multicast

one computer to a group of computers

replacing the cable with fiber optic cable

If your LAN server is overloaded, which of the following should you not consider (to solve the server problem)?

MAC address filtering

With _____________, the AP permits the owner to provide a list of valid addresses that can connect.

Access Point

A(n) ___________ is a radio transceiver that plays the same role as a hub or switch in a wired network and connects the WLAN to the wired network.

assigning each access point a different channel to communicate with clients

How can a set of 802.11b access points be configured to operate without interference?

False

The Ethernet standard was developed first by the IEEE.

True or False

File Server

A(n) ____________ allows many users to share the same set of files on a common, shared disk drive.

hidden node problem

When a computer transmits at the same time because it cannot sense that another computer on the WLAN is currently transmitting is referred to as the:

Collision Server

A(n) _____________ is not a common type of dedicated server.

2.4GHz and 5GHz

IEEE 802.11ac runs on which of the following two different frequency spectrums simultaneously?

True

802.11b LANs operate at speeds up to 11 Mbps.

True or False

Clients

Missing LAN Components:

1.___________

2. Servers

3. Network Interface Cards (NICs)

4. Network cables

5. Hubs / switches / access points

6. Software

Servers

Missing LAN Components:

1. Clients

2.__________

3. Network Interface Cards (NICs)

4. Network cables

5. Hubs / switches / access points

6. Software

Network interface cards (NICs)

Missing LAN Components:

1. Clients

2. Servers

3. ____________

4. Network cables

5. Hubs / switches / access points

6. Software

Network Cables

Missing LAN Components:

1. Clients

2. Servers

3. Network Interface Cards (NICs)

4.___________

5. Hubs / switches / access points

6. Software

Hubs / switches / access points

Missing LAN Components:

1. Clients

2. Servers

3. Network Interface Cards (NICs)

4. Network cables

5.________________

6. Software

Software

Missing LAN Components:

1. Clients

2. Servers

3. Network Interface Cards (NICs)

4. Network cables

5. Hubs / switches / access points

6.___________

Clients

Devices on the network that request information from servers

Servers

Devices on the network that deliver information or provide services to clients

Network interface cards (NIC)

-Also called network cards and network adapters

-Operate at layers 1 and 2

-Commonly built into motherboards

-Ethernet NICs contain unique MAC address

What is this?

Hubs and switches

-Link cables from different devices, sometimes more than one type of cabling

-Act as repeaters, reconstructing and strengthening incoming signals

What is this?

Access Points (APs)

Use radio waves to connect wireless clients to the wired network (instead of connecting using hubs/switches)

Network Operating System (NOS)

-Runs on devices and manage networking functions

-E.g., Novel NetWare, Microsoft Windows Server, Linux

-E.g., Cisco IOS or JUNOS on routers

What is this?

Software

-Provides directory services about LAN resources

-Network profiles specify resources that devices and users can access

What is this?

Logical

How the network works conceptually?

Physical

How the network is physically installed?

Physical star

Hub-based Ethernet uses ______________ topology.

Switch-based Ethernet

-Switch reads destination address of the frame and only sends it to the interface (physical port) connected to a circuit

-Uses forwarding tables (also called MAC or CAM tables), which are similar to routing tables

-Breaks up the collision domain

What is this?

Store and forward switching

Frames re-transmitted after entire frame is received and error check is complete.

HINT: slower, but fewer errors

Cut through switching

Frames re-transmitted as soon as destination address read

Fragment free switching

Frames re-transmitted once the header (first 64 bytes) is received and has no errors

Carrier Sense

A device "listens" to determine if another computer is transmitting

Multiple Access

Many devices have access to transmit on the network medium

Collision Detection

-Collisions occur when multiple devices transmit simultaneously

-If a collision is detected, wait a random amount of time and resend

What is this?

2.4 GHz range

-2.412-2.462 Ghz

-3 non-overlapping channels

What is this?

5 GHz range

-5.180-5.320 and 5.745-5.825 Ghz

-12 non-overlapping channels

What is this?

Identify bottlenecks

How can we improve throughput, the total data transmitted in a given period of time?

_______________

Servers

Clients

Networking devices

Circuits

Demand

Core Layer

The _________ is the part of the backbone that connects the different backbones together.

Routed Backbones

_________ move packets along the backbone based on their network layer address.

Rack

With a switched backbone network, the equipment is usually placed in a ______.

False

Layer-3 switches switch messages based on their data link layer address.

True or False

False

A VLAN network assigns computers to LAN segments by hardware.

True or False

True

The distribution layer of a backbone connects LANs together.

True or False

there are many more networking devices in a switched backbone network

Which of the following is not true about switched backbones?

performance is improved over traditional (bridged or routed) backbone networks

each connection into the switch is a separate point-to-point circuit which supports simultaneous access by the LANs connected to the switch

there are many more networking devices in a switched backbone network

if the switch fails, so does the entire backbone network

the backbone essentially exists in the switch; there is no backbone cable

Virtual LAN

A _____________ type of BN is a new type of LAN/BN architecture made possible by intelligent, high speed switches that assign computers to LAN segments via software, rather than by hardware.

coax cabling throughout LANs and BN

Which of the following would not be part of an "ideal" backbone design for the future?

access layer composed of 10/100 layer 2 Ethernet switches

distribution layer composed of layer 3 Ethernet switches of 100 (or 1000) Base-T

redundant switches

core layer composed of layer 3 Ethernet switches running 10 (or 40) GbE over fiber

coax cabling throughout LANs and BN

True

A room that contains a rack of equipment for a rack-based collapsed backbone is also called the main distribution facility (MDF) or central distribution facility (CDF).

True or False

Layer 2 switches

"transparent" devices that do not change messages, only read and forward them

Managed switches

have configuration options and management features

VLAN switches or layer-3 switches

are a devices combine the features of Layer-2 switches and routers, primarily for virtual LANs

Access layer

How users access network (LAN, WLAN)

Distribution layer

BN that connects access layer to core layer (within building)

Core layer

Connects BNs between buildings and to WAN/Internet

Switched backbones

Routed backbones

Virtual LANs

Three major types of BNs are based on the devices used

LAN segmentation

Subnetted backbones advantages

Tend to be slower

More expensive

Harder to manage

Subnetted backbones disadvantages

VLAN trunks

are circuits that connect two VLAN switches

VLAN tag

inserted into Ethernet frame (e.g., 802.1Q) or encapsulates frame (e.g. ISL)

More flexible

Better managed traffic flow which may lead to faster performance

Traffic prioritization

VLAN advantages

Complex

May increase management when VLAN memberships change

Layer 3 switches are more costly than L2

VLAN disadvantages

packet switched network

Which of the following type of networks permit packets from separate messages to be interleaved?

circuit switched network

dedicated circuit network

dial up circuit network

packet switched network

Fractional T-1 network

False

Full mesh networks are inexpensive.

True or False

False

A dedicated circuit is usually not available late at nights or on weekends.

True or False

False

Datagrams are connection-oriented.

True or False

True

Ethernet/IP packet networks are not provided by common carriers such as AT&T

True or False

True

Common carriers sell or lease communication services and facilities to the public.

True or False

provides a communications circuit with two 64 Kbps B channels, plus one D channel

Basic rate interface:

is typically offered only to commercial customers

provides a communications circuit with two 64 Kbps B channels, plus one D channel

is defined exactly the same way in Europe

has an upper capacity of 1.544 Mbps

is comprised of analog circuits only

Virtual private network

A _______________ is a particular type of network that uses circuits that run over the Internet but that appears to the user to be a private network.

local carrier network

virtual private network

integrated service digital network

software defined network

SONET network

False

An OC-1 circuit provides a data rate of 155 Mbps.

True or False