Switching Flashcards
0
Q
What are other names for the data link layer addresses ?
A
Physical
Hardware
Machine
MAC addresses
1
Q
Defines how devices are addressed at the data link layer
A
Physical addressing
2
Q
This defines how devices are to be physically and logically connected, such as in a bus or a ring topology
A
Network topology
3
Q
Reorders frames that are received out of sequence …
Also uses added bits to signal beginning and ending frames
A
Sequencing of data frames
4
Q
Moderates the transmission of data so that the receiving device is not overwhelmed with more traffic than it can handle at any one time.
A switches primary method of flow control is buffering
A
Flow control
5
Q
What are the 3 common methods of flow control?
A
Windows
Buffering
Source quench message
6
Q
This is a forwarding technique used in packet-switched networks.
A
Bridging
7
Q
What type of devices depend on flooding and examination of source addresses in received packet headers to locate unknown devices.
A
Bridging devices
8
Q
Bridges are _________ based
A
Software
9
Q
Switches are _________ based devices that use Application Specific Integrated circuits(ASIC) for faster operation.
A
Hardware
10
Q
What is the difference between bridges and switches spanning-tree control ?
A
Bridges have limited spanning tree control
Switches have advance spanning tree control
11
Q
Difference between the number of ports on a bridge vs a switch ….
A
Bridge max of 16 ports
Switches can have hundreds of ports
12
Q
Used to build and maintain MAC address(filter) tables
A
ASICs
13
Q
Commonly found between 2 different types of media access methods
A
Bridge
14
Q
These are used for workgroup connectivity and network segmentation
(Considered the predominate device for internet working)
A
Switch
15
Q
A physical or logical network segment in which data packets can collide with each other.
A
Collision domain
16
Q
A logical network segment defined by its router port connection
A
Broadcast domain
17
Q
When the host field contains all 1s
A
Directed broadcast
18
Q
All devices in this can communicate with each other by using broadcasts
A
Same broadcast domain
19
Q
A term referring to the hypothetical peak bit rate of a cable
(Useful information rate, 10,100,1000 Mbps)
A
Wire speed
20
Q
This term expresses how much time an event takes in networking
A
Latency
21
Q
Considered the most common type of switches
A
Ethernet switches
22
Q
Considered the “aggregation point” that connects network components such as computers and printers together
A
Ethernet switch
23
Q
What are the 3 major functions of layer 2 switches ?
A
Address learning
Forward/filter decision
Loop avoidance
24
To function smoothly the layer 2 switch must learn the MAC address of all devices that connect to it .... What is this called ?
Address learning
25
These use buffering and for receiving and transmitting
Switches
26
When does the switch overwrite information?
When it's full and the it takes the device that has been inactive for the greatest amount of time ?
27
If the destination hardware address is known and listed in the database, the frame is _______ out only on the correct interface
Forwarded
28
Helps to preserve bandwidth on other network segments
Frame filtering
29
What are the 3 frame switching methods ?
Store-and-forward
Cut-Through(Real Time)
Fragment-free(Modified Cut-through)
30
In this method the switch copies the entire frame into its buffers and computes the CRC
Best for sending error free frames because they are thoroughly checked
High latency (slow)
Store and Forward
31
With this method the LAN switch copies only the destination address onto its onboard buffers
( the first 6 bytes following the preamble)
Fastest processing - no error checking
Cut-Through
32
This method the switch waits for the first 64 bytes to pass before forwarding.
Provides better error checking than cut-through , with practically no increase in latency (delay)
Fragment free ( modified cut through )
33
A broadcast targets every device on the ______ by setting all the bits in the destination MAC address to 1
Subnet
34
Switches and bridges in a network environment can create __________________ in the topology.
Single point of failure
35
If loop avoidance schemes are not put in place the switches will flood broadcasts endlessly throughout the internetwork
Broadcast storms
36
When a device can receive multiple copies of the same frame because the frame can arrive from different segments at the same time
Multiple frame copies
37
Loops occurring within other loops
Multiple loops
38
Is designed to detect loops and close or open the necessary ports to avoid such loops
Spanning tree protocol (STP)
39
What are the two categories that an Ethernet can be categorized into ?
External and internal
40
The physical connections to the switch ...
Examples are console port and network interfaces
External components
41
This port allows locally direct access to the switch during configuration using a dumb terminal with software like Microsoft hyper term that is connected by a "rollover" cable
Console port
42
This is where you actually connect your end devices such as your computers or printers
Aka switch ports
Network interfaces
43
What are the four internal components ?
ROM
Flash memory
NVRAM
RAM
44
This is where the diagnostic and boot up routines are stored and the contents can't be changed since they are "burned in" to the chip
ROM
45
This holds the IOS
During startup operation the IOS is copied from this into RAM for execution
Flash memory
46
Non volatile memory
When the power is removed from the switch the content of this memory will remain unchanged
NVRAM
47
This is volatile memory
When power is removed from the switch the content of this memory will be lost.
This is also where the configuration file "run" and the IOS are executed during operation
RAM
48
This is a logical grouping of network computers and resources connected to administratively defined ports on a layer 2 switch
VLAN
49
This is also called a broadcast domain and all connected devices see all broadcast packets that are transmitted
Has a single broadcast
This design could be a single Ethernet segment , an Ethernet switch with many ports, or networks with several interconnected Ethernet switches
Flat Network
50
What are some benefits from creating VLANs?
Increased security
No geographical barrier
Flexibility and scalability
Broadcast control
51
This service will tell the switch port which VLAN it belongs to based on the MAC address of the device that connects to the port
Dynamic VLANs
52
With this VLAN membership, the administration creates VLANs and assigns the respected switch ports to it. This association is permanent and will not change until the administrator changes the port assignment
Static VLAN
53
Group of connected switches
Switch-fabric
54
What are the two types of links in a switched environment?
Access link
Trunk link
55
This protocol allows Cisco switches to automatically negotiate with other Cisco devices when they connect
Dynamic trunking protocol (DTP)
56
A link assigned to one VLAN
Access link
57
These are neutral, they will carry traffic for all VLANs unless you specify otherwise.
Trunk link
58
This is uniquely assigning a user-defined ID to each frame ?
Aka VLAN ID
Frame tagging
59
This is a Cisco proprietary protocol that is a way of encapsulating a VLAN frame with an added header and trailer.
Inter-Switch Link Protocol(ISL)
60
This process enables VLANs to be multiplexed over a trunk link
External encapsulation method
61
This Cisco protocol allows for the creation, addition, deletion, modification and synchronizing of VLANs from a central point of control within a administrative domain
VLAN Trunking Protocol (VTP)
62
What are the three VTP modes of operation?
Server
Client
Transparent
63
All switches that share VLAN information must .....
Use the same VTP domain name and VTP password
64
This mode is default for all Cisco switches
Server
65
What do VTP servers do ?
Create,add,modify, or delete VLANs in a VTP domain
Assign VLANs to switch ports
Synchronize configuration revision number with other servers
Send,receive,and forward VTP advertisements
66
Switches set to this mode will receive information form a VTP server via the trunk link using multicast message
Client
67
What are things that Client mode does ?
Receive VTP advertisements from switches in the server mode
Forward VTP advertisements to other clients
Synchronize configuration revision number with the server
Assign VLANs to switch ports if using Dynamic membership
68
This standard was created as anyone source standard method of frame tagging
IEEE 802.1q
69
This type of switch doesn't participate in the VTP domain, but they still receive and forward VTP advertisements through the trunk links.
Transparent
70
What are some actions that are accomplished in transparent mode ?
Create,add,modify or delete VLANs for itself only within the VTP domain
Assign VLANs to switch ports for itself
No synchronized with other switches
Receive and forward VTP advertisements but it doesn't process or synchronize to them
71
Switches In this VTP mode will receive information from a VTP server via the trunk link using multicast messaging
Client mode
72
This can forward received updates to other switches, synchronize itself to a revision number, assign the VLAN to a port(if using dynamic membership)
Client mode
73
Receive multicast from server , can't change, but can forward, assign VLANs if dynamic
Client mode
74
Only deals with advertisements not domain info, maintain own database
Transparent mode
75
This is set after the operational mode for VTP is set, the switch (server) will begin this on its trunk link to other switches in the domain.
VTP advertisements
76
What do VTP advertisements include ?
Management domain name
Configuration revision number
VLANs
And the parameters for each VLAN
77
Switches use what type of MAC addresses so all neighbor devices receive the frames
Multicast
78
What are the three types of VTP advertisements?
Client requests
Summary advertisements
Subset advertisements
79
This type of VTP address is sent out every 5minutes (300 seconds) on VLAN-1 to tell change (domain name, revision number, updater identity)
Summary
80
This type of VTP advertisement sends request for the VLAN info to the server. The servers in return will respond with both summary and subset advertisements
Client requests
81
This VTP advertisement are VLAN specific about each when a change occurs to trunk
Subset advertisements
82
When a client receives an advertisement that has a higher revision number it will overwrite the database in NVRAM with the database being advertised
Threat of higher revision numbers
83
To prevent disaster you would configure the switch to perform in the VTP mode that it will participate in , then save the configuration info and then add the switch to the internetwork.what is this process called ?
Adding a VTP domain
84
This is a standardized protocol that provides a stable, fault tolerant, loop free network environment while selecting the fastest network path when redundant links exist within an internetwork
Spanning tree protocol
85
This prevents loops on layer 2( bridges or switches) by using an algorithm to turn on 1 path and block the other unless the path breaks then it switches back
Spanning tree protocol (STP)
86
The entire switching domain or can be limited to each VLAN that's best path that doesn't form a loop
Spanning-tree instance
87
Switches communicate and root bridge selected to say port state
Selecting the best path
88
Layer 2 device in charge of STP ( lowest bridge ID)
Has designated ports to forward
Root bridge
89
All other switches are this ... , they block passing of data
Non-root bridge
90
What is used to find the root bridge by looking at lowest bridge id then MAC address?
Bpdu (bridge protocol data units)
91
A port that is active and that forwards traffic
Designated port (Forwarding)
92
This port are in forwarding mode and provide a constant connection to the root bridge from the non-root bridge so ads and updates are received
Root port(listening)
93
These ports are used to prevent loops.
Non-designated ports(blocked)
94
This occurs when bridges and switches have completed the transition to either forwarding or the blocking state.
Convergence
95
What are the 4 spanning tree port states ?
Blocking
Listening
Learning
Forwarding
96
This is what are all ports are in by default when the switch is powered on.
Will not forward frames
Only listens and process BPDUs
Blocking State
97
This is the state when it listens to BPDUs to make sure no loops occur on the network before passing data frames
Listening
98
This is another spanning tree port state that learns the MAC address and builds the MAC address filter table,but does not forward frames
Learning
99
The last spanning tree port state is when there are no redundant links or the port determines that it has the best path to the root bridge
Rarely ever happens
Forwarding
100
This used to speed up convergence on ports that are connected to workstations, servers or other devices that will not cause layer 2 loops
Spanning-tree Portfast
101
This is used to minimize network downtime by ensuring that network loops do not occur when the network topology changes.
Spanning-tree up link fast
102
The IEEE 802.1d and 802.1w are referred to as this .....
Common spanning tree(CST)
103
This was designed to operate on switches other than Cisco switches from other vendors
CST( common spanning tree)
104
This STP standard is Cisco proprietary implementation of STP.
This makes for smaller STP implementations with easier convergence.
Also default for Cisco switches
Per-VLAN Spanning tree (PVST)
105
This is an extension of PVST and and allows Cisco switches to operate with CST switches
And errors checks
Plug and play compatible
Per-VLAN Spanning Tree +(PVST+)
