Deck 3 Flashcards
Layer 2 tunnels encapsulate LWAPP traffic between what two points?
ALSO, what do these tunnels require of these two points?
-AP and the WLC
-IP addr on both ends
Layer 3 tunnels support what type of tunneling within Ethernet frames and UDP packets?
Also, they support UDP/UDP lite for which deploymens?
-LWAPP
-IPV6
devices communicate through a central device called an access point (AP). The access point serves as the hub or gateway
refers to a collection of one or more interconnected Basic Service Sets (BSS). A BSS is the basic building block of a WLAN (Wireless Local Area Network) and consists of one access point (AP) and multiple wireless clients
-infrastructure mode
-extended service set
option of WIFI where cells across different APs are linked together?
what does an independent basic service set do?
-distribution system
-allow direct comms between clients w/o a central access point
PortFast enabled on an interface connected to another switch immediately does what?
-immediately enables forwarding state
-can cause a broadcast storm (switching loops will be ignored)
Profile that is selected in GUI when configuring voice over WLAN?
Platinum
what command ensures a switch is ALWAYS and (THE ROCK MEANS ALLLWAYS!) the root for, say, a vlan 750?
(config)#spanning-tree vlan 750 root primary
what vlans must match when setting up trunking?
-Native vlans
service ports are used for what?
ALSO, what are dynamic interfaces used for?
-out of band management of a WLC
-communication for wireless clients
in a mobility group setup with WLCs in different places, it anchors inter-controller data
-virtual interfaces
A unified access point mode that continues to serve wirelessly after connectivity to LAN controller ceases?
-flexconnect
“show cdp neighbor” shows what?
-capability codes (R-router, s-switch, etc)
Static persistence (aka “on” mode), without negotiation, configures what between two switches?
-etherchannel
mode that allows APs to be managed by a Wireless LAN controller?
-what does it mean?
-LAP (lightweight)
-means can’t independent of a wireless controller
Creating a wlan in Cisco wlan controller. what MUST be created?
-ssid
-profile name
VTP mode of transparent means:
switch FORWARDS but doesn’t process VTP updates
with DTP, a dynamic auto switch is willing to become a trunk but…
what happens with a dynamic desirable switch?
won’t negotiate
-actively tries to negotiate trunking
Untagged PC data goes to a CISCO IP phone. What happens?
it goes thru unchanged
802.11b wireless infrastructure best practice is allocating…
nonoverlapping channels
to have untagged vlan traffic what must be done and whats the command?
make that vlan the native vlan for both connected interfaces on the switches
switchport trunk native vlan #
These commands are setting up an etherchannel. what kind and how?
-interface port-channel 10 no switchport and ip address 172.16.0.1 255.255.255.0
-interface GigabitEthernet0/0/1 channel-group 10 mode active
it’s a layer 3 etherchannel because “no switchport” and an IP address are there
-second command is assigning an interface to the created channel and using an open standard protocol (hence mode active which sets up LACP negotiation)
to create an etherchannel what two modes are used in a sequence? and why?
active and passive
ex: int range g0/0-1 channel-group 10 mode active
int range g0/0-1 channel-group 10 mode passive
TO ACHIEVE BALANCE
Phones and Computers, when configured proper don’t send traffic in the same…
vlan
command that enables the industry standard equivalent of Cisco’s CDP?
lldp run (from conf t)
3 lldp timers
-lldp holdtime
-lldp reinit delay (delay for lldp to initialize)
-lldp timer rate (sending frequency)
CDP neighbor has no IP. what happens?
Also what command is used to view IPs in cdp?
not much, cdp will go on normally
show cdp neighbor detail
LACP 3 modes?
PAgP 3 modes?
which is proprietary to cisco?
-active, passive, on
-on, desirable, auto
PAgP
what two vlan IDs indicate a default vlan?
1 and 1002-1005
what two things appear in CDP?
native vlan and vtp domain
PApG desirable and LACP active are equivalent in that they?
PApG auto and LACP passive are equivalent how?
-actively negotiate EtherChannel
-won’t negotiate. will only form if other end expresses interest (active for LACP, desirable for PApG)
for VTP, ALL switch must..
-be able to perform trunk negotiation
-use same VTP version
-root ports
-designated ports
-port with best BPDU/lowest cost to get to root bridge
-One per collision domain
I want to make a specific interface the preferred forwarder. What do I change?
the port priority
CDP best uses for an administrator, amongst others, are verifying layer 2 connectivity and providing
IPs
-CDP doesn’t give extensive VLAN info. What does?
-CDP does NOT show routing protocols but it shows interfaces. what else doesn’t it show?
-show vlan/brief
-cables used
