Chapter 1 Flashcards
What are the first hex digits of an IPv6 link-local address?
FE80
What are the first hex digits of an IPv6 multicast address?
FF
What are the first hex digits of an IPv6 unique local address?
FD or less commonly, FC
(binary format is 11111110)
What kind of IPv6 address is publicly routable?
Global unicast
What IPv6 address is private?
Unique local
How many bits long are IPv6 addresses?
128
What does an IPv6 address that pings all nodes look like?
FF02::1
What does EUI-64 do?
Generates the local, 64-bit, part of the IPv6 address from a 48-bit MAC address
7th bit of the MAC address is flipped, and FFFE is inserted in the middle
What happens if a PoE port exceeds the maximum administrative value for power?
The port is shut down and error-disabled
What is the most reliable WAN topology?
Full-mesh
What is a benefit of using a three-tier network topology over a collapsed core topology?
Increased redundancy and availability
Separation of core and distribution layer
Which network topology has the same number of hops between devices?
Spine-and-leaf
What is a disadvantage of full-mesh typologies?
Complex configuration
High cost
What WAN topology leverages a dedicated connection?
Point-to-point
Which part of an Ethernet frames helps the receiver know that it’s actual data?
Preamble
What does “media type is SFP-SR/LR” indicate?
The type of transceiver (small form-factor pluggable) being used, short reach/long reach
What is a benefit of using optical-fiber cabling as opposed to copper cabling?
Greater throughput
Support signals for longer distances
What is something that can cause a port to be placed in an error-disabled state?
Link flapping
Port security violation
What is something that can cause late collisions on an Ethernet interface?
Duplex mismatch
Exceeded cable length limits
FTP uses which ports?
TCP 20 and 21
SSH uses which port?
TCP 22
SMTP uses which port?
TCP 25
What kind of IPv6 address is equivalent to a public IPv4 address?
Global unicast
What kind of IPv6 address is used on a single link for purposes such as automatic address configuration, neighbor discovery, or in the absence of routers
Link-local
What kind of IPv6 address is not routable over the internet?
Unique local
What identifies a wireless network for an edge device to connect?
Service-set identifier (SSID)
What are the non overlapping 2.4GHz channels?
1, 6, 11
What service model provides ready-to-use software/applications?
Software-as-a-service (SaaS)
What kind of traffic does a switch use to build its MAC address table?
Ingress traffic
What does MAC address aging do?
Removes unused MAC addresses from the table after a certain period of inactivity
What does a hypervisor do?
Controls and distributes physical resources for each virtual machine, thus allowing them to communicate
What does a switch do if it receives a frame with an unknown destination MAC address?
Floods packets to all ports except for the receiving port in the given VLAN
What can a duplex mismatch cause?
Interface will still work but it may cause input errors, CRCs, late collisions, and runts
How might a duplex mismatch occur?
Old equipment, incorrect manual configuration, auto-negotiation issues
How would you avoid duplex mismatches?
Enable auto-negotiation on all Ethernet interfaces. If auto-negotiation is disabled or unsupported, configure both interfaces with the same duplex settings
What is a reason an interface might be in a down/down state?
The interface is error-disabled, speed mismatch
When is a collision classified as late?
Collision occurs after the first 64 bytes of the frame is received
What is a benefit of using 2.4GHz wifi over 5Ghz?
Longer range of coverage
What is a benefit of using 5GHz wifi over 2.4Ghz?
Transmits data faster, has 24 non-overlapping channels
What is a characteristic of an SSID?
32 alphanumeric characters
Case-sensitive
What 802.11 standards support only 5GHz frequencies?
802.11a, 802.11ac
What 802.11 standards support only 2.4GHz frequencies?
802.11, 802.11b, 802.11g
What 802.11 standards support both 2.4GHz and 5GHz frequencies?
802.11n, 802.11ax
What type of connectors are required for SFP and SFP+ optics?
LC (lucent connector = fiber)
What type of connectors are used with GBIC? (gigabit interface converter)
SC (square connectors)
What kind of architecture is broadband cable access good for?
SOHO
In physical layering standards, which Letter at the end represents twisted pair cable?
T
In physical layering standards, which Letter at the end can represent a fiber cable?
LX
LR
SR
E
What is the difference between UTP and STP cables?
STP cables are shielded and protect against EMI
What is a benefit of using optical-fiber cabling over copper cabling?
Faster speeds, carries signals for longer distances, not affected by EMI
What is the core size of OM3, OM4, and OM5 multimode fiber cables?
50 microns
What is the core size of OM1 and OM2 multimode fiber cables?
62.5 microns
Which mode of fiber is preferred for longer distances with little loss of integrity?
Single-mode
What is the core size of single-mode fiber cables?
9 microns
Describe E-Tree
Hub and spoke/partial mesh - all sites can communicate with the central site but not with each other
Describe E-Line
point-to-point service between two sites, multiple E-Lines can run on a single physical access link, so central sites can connect to several remote sites
Describe E-LAN
Full mesh, acts as an ordinary LAN where all sites can communicate directly with each other
Describe MPLS
A Layer 3 service where ISP creates a large IP network and connects all of its customers to it
Class A range
1.1.1.1-126.255.255.255
Class B range
127.0.0.0-191.255.255.255
Class C range
192.0.0.0-223.255.255.255
Class D range
224.0.0.0-239.255.255.255
Class E range
240.0.0.0-255.255.255.255
What IP address block is reserved by IANA for host loopback addresses?
127.0.0.0/8
What command is required to enable ipv6 routing?
ipv6 unicast-routing
What offers software or application on a subscription basis that is hosted on the cloud?
SaaS
What offers cloud services on a pay-as-you-go basis within a virtualized environment?
IaaS
What do the consumers manage in PaaS?
Application and data
What do the consumers manage in SaaS?
Nothing
What to do the consumers manage in IaaS?
Application, data, runtime, middleware, O/S
What is Google Suite and Office 365 an example of?
SaaS
What are some examples of IaaS?
AWS, Microsoft Azure, Oracle Cloud, IBM cloud
What is the default mac address-table aging time?
300 seconds
What command will save your configuration if “write” isn’t supported?
copy running-config startup-config
How do you view your ip info on windows cmd?
ipconfig
ipconfig /all
How do you refresh the DHCP IP command on windows cmd?
ipconfig /renew
How do you view a list of routes on windows cmd?
netstat -rn
How can you configure the switching mode?
switching-mode store-forward
(cut-through mode is enabled by default)
What is store-and-forward switching?
Packets with FCS errors are dropped
CPU ports automatically operate in this mode
It’s activated automatically when the port is oversubscribed
What class A addresses are reserved for private, internal use?
10.0.0.0/8
10.0.0.0 - 10.255.255.255
What class B addresses are reserved for private, internal use?
172.16.0.0/12
172.16.0.0 - 172.31.255.255
What class C addresses are reserved for private, internal use?
192.168.0.0/16
192.168.0.0 - 192.168.255.255
What does the FC do in an 802.11 MAC frame?
Used to indicate whether the frame is a management frame
Which types of IPv6 are not routable?
Link-local
Link-local multicast (FF01, FF02)
What is the maximum bandwidth of a CAT 5e cable?
1,000 Mpbs
What is the protocol that refers to private IP addresses?
RFC 1918
What range of MAC addresses is designated for Ethernet multicast?
0100-5e00-0000 through 0100-5e7f-ffff
What MAC address is used for Ethernet broadcast?
ffff-ffff-ffff
What is the 802.11 MAC frame format?
FC DUR ADD1 ADD2 ADD3 SEQ ADD4 DATA FCS
