Network and Security Foundations c172 Chpt 5

What are 3 advantages of using a bridge to interconnect LANs?

1) Easy to install 2) Reduces collision domains 3) relatively inexpensive

Name 3 functions of a bridge?

1) Only forwards data to the specified port. 2) Uses MAC address to forward data packets 3) Isolates the network Traffic

What are the Steps of the ARP Process?

1. Computer 1 checks its ARP cache to determine if it already has the MAC address of computer 2. If it does, it will skip to the final step; otherwise, it proceeds to the next step. 2. Computer 1 generates an ARP request message for computer 2 with its own MAC and IP information included. 3. Computer 1 then broadcasts the ARP request message on its local network. 4. Every local network device processes the ARP request message. Those computers that are not computer 2 will discard the message. 5. Only a match, which is computer 2, generates an ARP reply message and updates its ARP cache with computer 1 MAC and IP information. 6. Computer 2 sends an ARP reply message directly to computer 1. 7. Computer 1 receives the ARP reply message and updates its ARP cache with the MAC and IP of computer 2.

AUI Port

10 Mbps Ethernet Port. AUI="Attachment unit interface"

ARP Reply

A Network Protocol where the MAC address is returned

What is a disadvantage of the Auto Negotiation Protocol?

A failed negotiation on a functioning link can cause a link failure.

Bridge

A networking device that uses MAC address to forward data and interconnect 2 LANs.

Content Addressable Memory (CAM)

A table of MAC addresses and port mapping used by the switch to identify connected networking devices.

What hardware does Layer 3 switches use to handle switching functions?

ASICs to handle packet switching

Managed Switch

Allows the Network admin to monitor, configure and manage select network features

ARP Table

Another Name for ARP Cache (Temp Storage of MAC addresses recently contacted)

Multiport Bridge

Another name for layer 2 switch (Improved network technology that provides a direct data connection for the network devices in the a LAN. )

Network Address

Another name for the Layer 3 address

Broadcast domain

Any network broadcast sent over the network will be seen by all networking devices on the domain

Console Cable

Cable that connects the router's console port to a computer's Serial port

Fast Link Pulse (FLP)

Carries the configuration info between each end of the data link and is used for Auto-negotiation

CSU/DSU

Channel Service Unit/Data service unit

Serial Interfaces on a router are typically used to connect to what?

Communication carriers

COM1, COM2...

Computers serial communication ports

DTE

Data Terminal Equipment = The serial interface designed for connecting to a CSU/DSU to outside digital communication services

Wire speed Routing

Data packets are processed as quickly as they arrive

Logical Address

Describes the IP address location of the network and the address location of the host in the network.

The AUI port on a router connects to which network Protocol?

Ethernet

What is the most commonly used router interface used to interconnect LANs in a campus network?

Ethernet

What Router interfaces are used to connect routers to the network?

Ethernet, Serial , and Auxiliary

Broadcast storm

Excessive amounts of broadcasts

Auto-negotiation uses the fasted Data rate on the link True or False

False - the link can only go as fast as the slowest link

Layer 2 switch

Improved network technology that provides a direct data connection for the network devices in the a LAN.

Association

Indicates that the destination address is for a networking device connected to one of the ports on the bridge,

Transparent bridge

Interconnects 2 LANs the same type of protocol

Bridging Table

List of MAC addresses and Port locations for hosts connected to the bridge ports

Dynamic Assignment

MAC address are assigned to a port when a host is connected.

Cisco Network Assistant (CNA)

Management Software tool for Cisco that simplifies switch configuration and troubleshooting

What are the advantages of Auto-negotiation?

Maximize the data link throughput, Is useful in LANs that have multiple users with multiple connection capabilities, and Simplifies the LAN config

Multicast

Messages are sent to a specific group of hosts on teh network

Another name for Switch

Multiport bridge

Fast Ethernet Port (FA0/0, FA0/1, FA0/2,...)

Naming of the Fast Ethernet ports on the router

Serial Port (S0/0, S0/1, S0/2,...)

Naming of the serial ports on the router

A router uses what to make routing decisions regarding forwarding data packets?

Network address

What is a Logical address?

Network address

Gateway

Network device that enables the Hosts in the LAN to connect to Networks (and Hosts) outside the LAN

Enterprise Network

Network used by a large company

What are the disadvantages of Auto-negotiation?

Not recommended for fixed data links such as the backbone in a network, and a Failed negotiation on a functioning link can cause a link failure.

Multi-layer switch (MLS)

Operates on Layer 2 but functions at the higher layers

Echo Request

Part of ICMP protocol that request a reply from a computer

Auto-negotiation

Protocol used by interconnected electronic devices to negotiate a link speed

Console Input

Provides an RS-232 serial communication link into the router for initial router configuration. A special cable, called a console cable is used to connect the console input to the serial port on the computer. The Console cable uses RJ-45 plugs on each end and requires the use of an RJ-45 to DB9 adapter for connecting to the COM1 or COM2 serial ports.

Serial ports

Provides the serial data communication link into and out of the router, using v.35 serial interface cables

What type of connections are used for routers Console?

RJ-45 and ES-232

ARP Cache

Temp Storage of MAC addresses recently contacted

An association indicates what?

That the destination address for the networking device is connected to one of its ports.

Cut-Through

The Data packet is forwarded to the MAC address as soon as the destination MAC Address has been read

Static addressing

The MAC address has be manually assigned to a switch port

Error threshold

The Point where the number of errors in the data packets has reached the threshold and the switch changes from the cut-through to the Store and forward mode.

Store-and-Forward

The entire frame of data is received before any decision is made regarding forwarding the data packet to its destination

Aging Time

The length of time a MAC address remains assigned to a port

Router interface

The physical connection where the router connects to the network

Advertise

The sharing of route infomation

Secure address

The switch port will automatically disable itself if a device with a different MAC address connect to the port

Broadcast

Transmission of data by a network device to all devices connected to its ports

A bridge looks for an associate between a MAC address and a port. True or False

True

The gateway describes the address of the primary networking device that connects to the area outside the Local LAN. True or False

True

Power On/Off

Turns on/off electrical power to the router

Media Convertor

Used to adapt a layer 1 (physical layer) technology to another layer 1 technology

Auxiliary Input

Used to connect a dial-in modem to router. provides an alternative way to remotely log in to the router if the network is down. Port uses a RJ-45 connection.

Address Resolution Protocol (ARP)

Used to map IP address to its MAC Address

A 2 layer switch does what?

Uses the MAC Addressing for the Data link layer and Provides a direct connection for networking devices on the LAN

Network Slowdown

degraded network performance

Routing table

keeps track of the routes to use for forwarding data to its desitnation

Flooding

term used to describe what happens when a switch doesn't have the destination MAC address stored in the CAM.

Switch Latency

the length of time a data packet takes from the time it enters a switch until it exits

Translation bridge

used to interconnect 2 LANs that are n 2 different networking protocols

What is the command to view the ARP Cache?

arp -a

Isolating the Collision domains

breaking the network into segments where a segment is a portion if the network where the data traffic from one part of the network is isolated form the other networking devices.

Half-Duplex

communication device can transmit or receive but not at the same time