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
