WiFi Flashcards
3 types of 3G connections:
- WCDMA (older)
- HSPA (3.5G)
- HSPA+ (3.75G)
4G speed
up to 1Gbps
- uses MIMO
4G LTE Long-Term-Evolution (-A Advanced)
5G
multiple frequencies, way faster, but smaller coverage areas from one antenna
- low band (slower, but wider coverage)
- mid band (most popular)
- high band (extremely high speed, but very tricky)
2 cellular technologies
GSM
CDMA (NO SIM card)
–> now both using WCDMA
Microwave frequencies
UHF / SHF/ EHF
- uses WiMAX
- -> MUST maintain line of sight
- -> used for internal WAN connections between campuses
Dedicated Lease Line
T1 (1.5 Mbps) / T3 (45 Mbps) / E1 (2 Mbps) / E3 (35Mbps)
–> CSU/DSU connects customer to a T1/E1 (specialised serial ports)
Metro Ethernet
–> cheaper alternative to leased lines
–> RJ-45
PPP
point-to-point protocol: L2 prot used on top of dedicated leased lines to transmit multiple L3 protocols (IP, IPX)
Point-to-Point Protocol (PPP) provides a standard way to transport multiprotocol data over point-to-point links;
within PPP, Link Control Protocol (LCP) establishes, configures and tests data link internet connections on L3 (authentication, packet size, basic error checking etc.).
benefits of PPP
- authentication (PAP ! plaintext / CHAP / MS-CHAP)
- error detection
- multilink interface
- looped link detection
PPPoE
PPPoE encapsulates Point-to-Point Protocol (PPP) frames inside Ethernet frames, offering the same benefits as PPP, while providing connectivity across Ethernet networks.
–> authentication over Ethernet
which two wireless standards can be used interchangeably?
802.1 b & 802.1 g
Your company is currently using a 5 GHz wireless security system, so your boss has asked you to install a 2.4 GHz wireless network to use for the company’s computer network to prevent interference. Which of the following can NOT be installed to provide a 2.4 GHz wireless network?
Wireless networks are configured to use either 2.4 GHz or 5.0 GHz frequencies, depending on the network type. 802.11a and 802.11ac both utilize a 5.0 GHz frequency for their communications.
Which type of wireless network utilizes the 5 GHz frequency band and reaches speeds of up to 54 Mbps?
The wireless 802.11a standard uses the 5 GHz frequency band and can reach speeds of up to 54 Mbps. Unfortunately, when this was first released, the radios to operate with this standard were fairly expensive, so it did not sell well or become widespread.
Which type of wireless network utilizes the 2.4 GHz or 5 GHz frequency bands and reaches speeds of 108 Mbps to 600 Mbps?
The wireless 802.11n standard supports the use of either the 2.4 GHz or 5 GHz frequency band and can reach speeds of up to 108 Mbps to 600 Mbps. Wireless N (802.11n) is backward compatible with Wireless A, B, and G.
You’ve been asked to deploy a wireless network that supports a minimum distance of 35 meters indoors and offers fast speeds. You are choosing a wireless access point that accommodates the right protocol for the job. Which wireless standard should the AP support?
The IEEE 802.11n standard offers a max theoretical distance of 70 meters indoors and a max theoretical speed of 600 Mbps through the use of channel bonding.
