CCNA Wireless Chapter 9 answers

In a wireless model, frames generally go from a lightweight AP to a WLC

A WLC is…
A WiLAN controller

Active scanning is…
When a client sends probes out

Passive scanning is..
When a client waits for beacons

What comes first, the auth request or the assoc request frame when a client attempts to connect to an AP?
The auth request comes first

Briefly count off the steps for wireless association to an AP
1) Client sends probe
2) AP sends probe response
3) Client sends auth request
4) AP sends auth response
5) Success message sent
6) Association request sent by client
7) Association response sent by AP
8) Client uses RSSI and SNR to determine what speed to send at

Management frames are sent at the …
Lowest possible rate

Data headers are sent at the…
Lowest possible rate

Actual data is sent at the…
Highest possible rate

If a wireless client is sending to a host on a different subnet and has never done so before, it will need to perform the ___ operation to find the ____ address of the __________ gateway
ARP, MAC, default

In an ARP frame sent from a client, the source address is the…the destination address is the…and the receiving address is the…
Host sending ARP
Broadcast because its an ARP broadcast
AP

What interframe space do ACK frames use?
SIFS – short interframe space

The LWAPP adds a ____________ _____________ frames travelling from the AP to the WLC
6 byte header

Who translates 802.11 frames into 802.3 frames in a centralized wireless setup?
The wireless LAN controller

The two main types of WLAN implementation methods are:
1) Distributed (autonomous AP’s)
2) Centralized (LAP + WLC)

WLC’s are responsible for… (5 things)
1) Security policies
2) Intrusion prevention
3) RF management
4) QoS
5) Mobility

LAP’s handle real-time MAC layer services while WLC’s handle non-real-time MAC layer services

Non real time MAC layer services handled by the WLC include:
1) Authentication
2) Association and reassociation (aka mobility)
3) Frame translation and bridging

Public networks broadcast their SSID in a beacon
But private networks wait for probe-requests

In a distributed setup, the address fields are setup as follows in the 802.11 frame:
Field 1: AP = receiving address
Field 2: Source address
Field 3: Destination address
Field 4: Unused

The Ethertype of LWAPP is…
0xBBBB

LWAPP can operate at ______ or ______
Layer 2 or layer 3

If LWAPP is operating at L2, do AP’s need IP’s?
No.

If LWAPP is operating at L3, do AP’s need IP’s?
Yes.

The trunking protocol is called…
802.1q

The trunking protocol adds a ____________ to 802.3 frames
4 byte header

The header added by 802.1q contains what 2 things
1) TPID
2) TCI

The TCI contains…
User priority, 1 bit canonical format, 12 bit VLAN ID

What are the reserved VLAN ID’s?
1 = default
1002 = FDDI
1003 = TR
1004 = FDDINET
1005 = TRNET