Networking Fundamentals - Objective 1 Flashcards
OSI model, Network topologies & types, cables & connectors, IP addressing, protocols & ports, network services, corporate & datacenter architecture, cloud
FDDI
A fiber ring topology that uses two counter-rotating rings for redundancy [on the N10-008 “ring” always means FDDI ring]
Formula for calculating the number of connections in a full-mesh network topology
x=n(n-1)/2
Multiplexing
Simultaneous use of baseband connection by more than one device
In which OSI layer do WAPs operate?
Layer 1
In which OSI layer do media converters operate?
Layer 1
In which OSI layers do NICs operate?
Layers 2 & 1
In which OSI layer do bridges operate?
Layer 2
3 things handled by the MAC sublayer
- creating& addressing frames
- checking the FCS
- sending data to layer 1
3 things handled by the logical link control sublayer
- communication with the OS via drivers
- network protocols
- flow control
H.323
Used to set up, maintain, & tear down a voice/video connection
What protocol does H.323 & H.264 operate under?
RTP Real Time Protocol
2 main functions of OSI layer 6
- data formatting
- encryption
2 main functions of OSI layer 7
- Application services e.g. file transfer
- Service advertisment
RST flag
Reset flag
Used when a client or server receives a packet that it was not expecting during the current connection
PSH flag
Push flag
Used to ensure that the data is given priority & is processed at the sending or receiving ends
URG flag
The urgent flag
Indicates data of the highest priority which should be immediately processed
EtherType Field
Indicates which protocol is encapsulated in the payload of the frame
What does the OSI application layer refer to?
The code (API) built into all operating systems that enables network-aware applications
2 major functions of the OSI transport layer
Segmentation & reassembly
SFTP full name and port number
SSH File Transfer Protocol
22
Protocol used to boot an OS from a LAN file server
TFTP
Active Directory port number
TCP 389
System Logging Protocol (Syslog)
What port number do servers listen on?
UDP 514
SMTP TLS
Port number
TCP 587
LDAPS
Port number
TCP 636
IMAP over SSL
Port number
TCP 993
POPv3 over SSL
Port number
TCP 995
SQL
Port number
TCP 1433
SQLnet Protocol function
Communication from client to an Oracle database
MySQL function
Communication from a client to the MySQL database engine
SQLnet Protocol
Port number
TCP 1521
MySQL
Port number
TCP 3306
RDP
Port number
TCP 3389
SIP
Port number
TCP or UDP
commonly:
5060 non-encrypted
5061 encrypted with TLS
Which coaxial cable is used to connect the ISP service to a home?
RG-6
Which coaxial cable is used to connect a wall cable to a cable modem
RG-59
MDIX
Medium Dependent Interface Crossover
An automated way to electronically simulate a crossover cable connector
What is non-plenum cable also known as?
PVC
MTRJ
Mechanical transfer registered jack
The smallest fiber connector
APC
Angled Physical Contact Connector
Fiber cable end polished at an 8 degree angle making for less signal noise
UPC
Ultra Physical Contact Connector
Fiber cable end polished flat (no angle)
APC & UPC are used by which connectors, respectively?
SC & MTRJ
APC & UPC connectors are usually what colors, respectively?
Green & blue
Maximum number of channels supported by CWDM
18
Maximum speeds supported by Ethernet & fiber CWDM, respectively
10 & 16 Gbps
SFPs & QSFPs
Small Form Factor Pluggable
&
Quad Small Form Factor Pluggable
Optical module transceivers of different types operating at speeds from 4.2-200 Gbps
GBIC
Gigabit Interface Converter
Gigabit Ethernet transceiver used for copper or fiber
Range of first octet of a class A IP address
1-127
Range of first octet of a class B IP address
128-191
Range of first octet of a class C IP address
192-223
Range of first octet of a class D IP address
224-239
Range of first octet of a class E IP address
240-255
Private class A address range
10.0.0.0 -
10.255.255.255
Private class B address range
172.16.0.0 -
172.31.255.255
Private class C address range
192.168.0.0 -
192.168.255.255
Loopback address range
127.0.0.0 -
127.255.255.255
APIPA address range
169.254.0.0 -
169.254.255.255
Steps of the DHCP 4-way handshake
Discover
Offer
Request
Acknowledgement
RFC 1918
Request for Comments 1918
Specifications for assigning private IP addresses
SLAAC
Stateless Address Autoconfiguration
How a system creates for itself an IPv6 link local address
Eliminates the need to obtain addresses or other configuration information from a central server
How a IPv6 link-local address begins
FE80
How a IPv6 multicast address begins
FF
3 main benefits of IPv6 over IPv4
- No broadcasts
- No fragmentation
- Simplified header
Number of bits is a hexadecimal digit worth
4 bits
Number of bits in an IPv6 address
128 bits
NDP redirect function
Routers informing host of better first-hop routers
NDP
Five main functions
Neighbor Discovery Protocol
- Router solicitation and advertisement
- Neighbor solicitation and advertisement
- Redirect
IP Class D purpose
Multicast
DHCP Relay
Forwards DHCP packets between clients and servers 
Situation in which DHCP relay is necessary
When the client device and the DHCP server are not located on the same subnet or network 
IP Helper
Forwards several different kinds of UDP broadcasts across the router and can be used in conjunction with the DHCP relay
Maximum number of NTP stratum levels
15 levels
Physical makeup of cable modem networks
A cable television infrastructure that is a hybrid fiber-coax (HFC) distribution network
DOCSIS
The standard that determines the frequencies used in cable modem networking
Sizes of ATM header and payload
Five bites and 48 bites
T1 max speed
1.544 Mbps
T3 max speed
44.736 Mbps
E1 max speed
2.048 Mbps
E3 max speed
34.4 Mbps
ATM max speed range
OC-3: 155 Mbps
up to
OC-12: 622 Mbps
SONET max speeds
OC-1: 51.84 Mbps
up to
OC-3072: 159.25 Gbps
mGRE
Multipoint Generic Routing Encapsulation
Enables one node to communicate with many other nodes.
Used on a router at a main office to facilitate multiple VPN connections
VPN protocol usually paired with mGRE
DMVPN
2 benefits of DMVPN
- security
- no need to statically configure all the VPN endpoints
FC
Fibre Channel
Special purpose hardware providing 1-16 Gbps of storage area network speed
SAN
Storage Area Network
Specialized LAN that transfers data at block-level with a special protocol
FCoE
Fibre Channel Over Ethernet
Runs FC over Ethernet networks instead of specialized hardware
iSCSI
$ cost & configuration
IP Small Computer System Interface
Lowers cost & relies on configuration that allows jumbo frames over the network
Default & jumbo frame sizes
1500 & 9000 MTU
InfiniBand:
- what it is
- 4 characteristics
- where it’s used
A virtualized storage technology
- Switched fabric topology
- Very high throughput
- Very low latency
- Expensive
Big datacenters
Orchestration
The process of arranging or coordinating the installation & configuration of multiple systems
4 protections provided by IPSec
- CIA
- Anti-Replay
DNAT
Dynamic Address Translation
A type of NAT in which many computers can share a pool of routable IP addresses that number fewer than the computers
SFP typical max speed
1 Gbps
SFP+ typical max speed
10 Gbps
Type of fiber cable that has a yellow sheath
SMF
Type of fiber cable that has an aqua blue or orange sheath
MMF
CWDM
max number of channels & speeds
Coarse wavelength division multiplexing
- 18
- Ethernet: 10 Gbps
- Fiber: 16 Gbps
DWDM
max number of channels & speeds
Dense wavelength division multiplexing
- 80
- 8 Tbps (100 Gbps per channel)
Baseline Configurations
Set of specifications for an information system, or a configuration item
within a system, that has been formally reviewed and agreed on
- Changes will be properly tested and approved to be part of the new
baseline
A way to segment BYOD devices
Create a segmented network where devices can connect directly to the internet & then use cloud-hosted resources
3 tiers of a 3-tier architecture
- Core
- Distribution
- Access
Spine and Leaf Architecture
2 bullet points
Associated with top-of-rack switching where each leaf is a switch on top of a rack
- Each leaf connects to each spine switch
- Leaves do not connect to each other
Advantages (3) and disadvantage (1) of spine and leaf architecture
- Simple cabling
- Redundant
- Fast
- Additional switches may be costly
East-west traffic flow
Traffic between devices in the same data center
North traffic flow
Data exiting the data center
Resource pooling
Cloud providers serving multiple clients with provisional and scalable services
Site-to-site vs. client-to-site VPN setup
Client-to-site requires client software to be installed & uses two concentrators.
Site-to-site requires a router to be configured.
3 types of IPv6 addresses
- Unicast
- Multicast
- Anycast
Beginning of a globally routed IPv6 address
Any number from 2000 to 3999
2 types of IPv6 unicast addresses
- Globally routed
- Link-local
LDAP port number
TCP or UDP 389
South traffic flow
Data entering the data center
What a router will do with a packet it has no entry for in its routing table
Drop the packet
ICMP
A set of communication rules that devices use to communicate data transmission errors in a network
5 IP protocol types
- ICMP
- TCP
- UDP
- GRE
- IPsec
VIP
Virtual IP
An IP address that does not correspond to a single physical network interface
Some things (6 things) an IPS can do
- Send an alarm
- Create correlation rules & remediation
- Drop malicious packets
- Provide malware protection
- Reset the connection of offending source hosts
- Close ports
6 types of IPv6 tunneling
- Manual
- GRE
- 6to4
- Automatic 6to4
- ISATAP
- Teredo
Benefits of spine-and-leaf over 3-tier
- Scalability
- Lower latency
- Increased bandwidth
What happens to data as it travels from Layer 7 to Layer 1 of the OSI model
Encapsulation