CUC Solutions Flashcards
1
Q
What line of Cisco products enables real-time video communications?
A
Cisco Unified Video Advantage
2
Q
What is the maximum number of IP phones supported on CME?
A
450
3
Q
Name two examples of voice applications that use Tcl scripts.
A
Basic ACD and Cisco IP AutoAttendant
4
Q
What CME feature provides support for third-party applications?
A
Cisco Telephony Application Programming Interface (TAPI)
5
Q
What two protocols does CME use to communicate with IP phones for call setup and signaling?
A
SIP and SCCP
6
Q
What router-based Cisco product provides IVR capabilities?
A
Cisco Unity Express
7
Q
What’s the name of the feature that allows CME admins to maintain contact information?
A
Directory services
8
Q
What CME feature extends the product’s feature set to desktop applications?
A
Computer telephony integration (CTI)
9
Q
What two protocols can CME use to trunk voice calls over the WAN to CUCM?
A
H.323 and SIP
10
Q
Describe how Cisco Unity Express communicates with CME running on the same router.
A
It uses SIP.
11
Q
What voice codecs does Cisco Unity Express support?
A
G.711 only.
12
Q
How many unsecured IP phones can a CUCM cluster support?
A
30,000
13
Q
How many secured IP phones can a CUCM cluster support?
A
27,000
14
Q
What protocol does the CUCM Disaster Recovery System use to perform backups?
A
SFTP
15
Q
What is the make and model of the database used by CUCM?
A
IBM Informix
16
Q
Name the five Cisco platforms supported by the Cisco Unified Operating System.
A
Cisco Unified Communications Manager Cisco Emergency Responder Cisco Unity Connection Cisco Unified Presence Cisco Unified Contact Center Express
17
Q
What are the minimum CPU, RAM, and hard drive sizes for a CUCM installation on a physical server?
A
2 GHz CPU
2 GB RAM
72 GB hard drive
18
Q
With what CUCM version did Cisco begin supporting installations on VMs?
A
8.0
19
Q
How many end users can a CUCM installation support in a virtualized environment?
A
7,500
20
Q
What Cisco Unified OS application is used to migrate CUCM from a physical server to a virtual server?
A
The Disaster Recovery Framework
21
Q
When CUCM is installed on a VM, what is used for the MAC address that’s required for licensing?
A
A hash of a set of data on the server
22
Q
What is the maximum number of CallManager publishers and subscribers allowed in a CUCM cluster?
A
One publisher, eight subscribers
23
Q
How many CUCM instances can be grouped together for IP phone registration redundancy?
A
Three
24
Q
How many CallManager instances can an IP phone register with to maximize redundancy?
A
Four (three in a group, plus SRST)
25
Name the three factors that affect how many subscriber servers are added to a CUCM cluster.
Redunancy
Load sharing
Scalability (number of phones supported)
26
What is the user count threshold for when Cisco recommends a dedicated TFTP server?
1,250
27
How many TFTP servers can be configured in a CUCM cluster?
2
28
What is the definition of a CUCM server cluster?
A group of servers that share the same SQL database
29
Which servers in a CUCM cluster have read-write copies of the SQL database?
Just the publisher
30
Give the two primary reasons CME steps out of the middle of the RTP stream between two phones.
1. It eliminates the router as a point of failure.
| 2. It prevents the router from becoming a bottleneck.
31
Name the two form factors that CUE comes on and the two primary differences between them.
The Internal Services Module (ISM) and Services Module (SM). The ISM is installed inside the router and uses flash memory; the SM is installed from the outside and uses a hard drive.
32
Name the two types of communication used within a CUCM cluster.
Intracluster Communication Signaling (ICCS), which shares device registrations, location bandwidth, and media resources.
2. CDRs/CMRs
33
What ports does ICCS use?
TCP 8002-8004
34
What do CUCM subscribers do with CDRs and CMRs when the publisher is unreachable?
They are stored on the hard drive.
35
Where does the CUCM publisher store CDRs and CMRs?
In the CDR Analysis and Reporting database (CAR).
36
What protocol property do applications use to support advanced features while interoperating with less functional applications?
SIP protocol extensions
37
Name the two primary functions of the CUCM publisher.
1. Maintain the SQL database
| 2. Respond to TFTP requests
38
Name the CUCM click-to-call application that allows users to place calls from their PCs using any supported phone device.
Cisco WebDialer
39
What are the minimum CPU, RAM, and hard drive sizes for a CUC installation?
2 GHz CPU
2 GB RAM
146 GB hard drive
40
What installation practice would allow upgrades to CUC without bringing down the server?
Dual partitions running CUC concurrently.
41
How many CUCM servers can a phone know about for redundancy purposes?
Three
42
True or False: When the CUCM publisher is unavailable, subscribers copy user-facing data among themselves until the publisher returns.
Yes
43
How many mailboxes can Cisco Unity Express support?
300
44
Active/Active or Active/Standby: What type of redundancy does CUC use?
Active/Active
45
How many mailboxes can CUC support?
20,000
46
What CUCM version permits CUC to be installed on the same physical server?
CUCM Business Edition
47
How many voice mail ports can a redundant CUC implementation support?
500
48
Name four types of calls whose frequency and duration should be considered when sizing CUC voice mail ports.
1. Calls to the auto-attendant
2. Checking voice mail
3. Leaving voice mail
4. MWI on/off
49
How does CUC inform a phone user that he or she has a voice mail waiting?
It places a call to the MWI On extension on CUCM.
50
How does CUC know which mailbox to send a message to when a call is routed to it after a phone user doesn't pick up?
The call information coming from CUCM includes the called party.
51
This set of Internet multimedia messaging protocols, including MIME, is supported by CUC for integration between several types of messaging platforms.
Voice Protocol for Internet Mail (VPIM)
52
How is the CUC publisher chosen in an Active/Active server pairing?
It's the first one installed.
53
What CUPS structure enables an industry standard for collaboration between different user clients?
The Jabber Extensible Communications Platform (XCP)
54
Name the two ways of determining current presence status.
1. Automatic events (e.g., phone off hook)
| 2. Explicit settings (e.g., DND)
55
Name two protocols that XCP can use to interoperate with non-CUPS applications like Google Talk.
1. SIP
| 2. Extensible Messaging and Presence Protocol (XMPP)
56
Define "persistent chat."
It's a permanent chat session that users can join and see the conversation history.
57
Name the two protocols that CUPS supports for encryption between itself and applications.
1. IPSec
| 2. TLS
58
What protocol is used for secure communication between CUPS and CUPC?
HTTPS
59
What video codec is used by CUPC?
H.264
60
What two protocols does CUPS support for presence and IM?
1. SIP Instant Messaging and Presence Leveraging Extensions (SIMPLE)
2. XMPP
61
What protocol is used for presence notifications between CUCM and CUPS?
SIMPLE
62
What key CUCM feature is not supported by CUCM Business Edition?
Redundancy
63
How many call processing servers are supported in a CUCM cluster?
8
64
Define "glare" in a telephony context. With what type of signaling does it occur?
Glare occurs when a user picks up a phone to make an outgoing call at the same time an incoming call arrives. It happens with loop start signaling.
65
What type of analog signaling eliminates glare?
Ground start signaling
66
How are loop start and ground start signaling different?
In loop start signaling, the circuit is opened when the phone is remove from the hook. In ground start signaling, the CPE sends a ground signal on the wiring to indicate to the CO that the circuit should be opened.
67
What is the most common type of analog trunk?
E&M
68
Name the three types of analog voice interfaces supported by Cisco gateways.
FXS, FXO, E&M
69
What three items are provided to analog phones by FXS ports?
Dial tone, ring, voltage
70
Of the two primary types of digital voice circuits, which uses "robbed bit" signaling?
Channel associated signaling (CAS)
71
Of the two primary types of digital voice circuits, which uses a separate signaling channel?
Common channel signaling (CCS)
72
In-band or out-of-band: What type of signaling does E&M use?
Out-of-band. (Its signaling paths are separate from the trunk audio.)
73
Name the three types of digital voice circuits supported by Cisco.
T1
E1
BRI
74
This type of device provides translation between different VoIP networks and VoIP or non-VoIP networks such as the PSTN.
Gateway
75
In robbed-bit signaling, which bit(s) are "robbed"?
The eighth bit of every sixth frame
76
Name the most common CCS signaling protocol.
Q.931
77
Name the timeslots used for voice signaling on T1 and E1 PRI circuits (they're different).
T1s use Channel 24; E1s use Channel 17.
78
Name three reasons why CCS is more popular than CAS.
1. More signaling message flexibility
2. More bandwidth for voice signaling
3. Higher security
79
Name the two types of trunks that IP telephony service providers may provide to customers.
SIP and H.323
80
Name the Cisco device that serves as a demarcation point between two VoIP networks.
Cisco Unified Border Element (CUBE)
81
The modified URL addressing scheme used in SIP is based on what other common Internet protocol?
SMTP
82
A Cisco CUBE can process calls controlled by what two protocols?
SIP and H.323
83
Name and briefly describe the three types of cards found in a traditional PBX system.
Line cards - connect to handsets
Trunk cards - connect to the PSTN
Control complex cards - handle call setup, control, and management
84
Name the three components in the E.164 numbering plan.
Country code
National destination code
Subscriber number
85
Name the four parts of the North American Numbering Plan and identify which E.164 component each falls under.
Country code - E.164 country code
Area code and central office code - E.164 national destination code
Station code - E.164 subscriber number
86
Define "quantization."
It's the process of converting an analog wave into digital values.
87
Name three uses for a media termination point (MTP).
1. Transcoding between a-law and mu-law
2. Bridge two connections that use different packetization periods/packet sizes
3. Convert DTMF signals
88
What process does the G.711 codec use to convert analog sounds into digital streams?
Pulse Code Modulation (PCM)
89
What bandwidth does CUCM assume is used by G.722? When is it usually used?
64 Kbps. It's used in LAN deployments.
90
Why would someone choose G.722 over G.711?
It offers improved voice quality.
91
Name two common high-complexity voice codecs.
G.729 and G.729B
92
How much bandwidth does G.729 consume?
8 Kbps
93
How much bandwidth does G.729A consume? Why would one use it instead of G.729?
8 Kbps. It's used because it is less complex.
94
What's a downside to choosing G.729A over other low-bandwidth codecs?
It's prone to "tandeming," a form of distortion that occurs with repeated encoding.
95
How much bandwidth does iLBC consume? Why would one choose it?
13.3 Kbps. It provides higher quality and better response to packet loss than G.729A.
96
How much bandwidth does iSAC consume? Why would one choose it?
32 Kbps. It's robust to jitter and packet loss.
97
Which codec(s) have a variable bit rate?
iSAC (CUCM calculates it for 32 Kbps, but it ranges from 10 to 32)
98
Name two features of G.729B.
VAD and comfort noise generation (CNG)
99
What are the trade-offs between G.729AB and G.729B?
G.729AB is medium complexity, but it has slightly lower quality.
100
What is the typical bandwidth savings from VAD?
35%
101
The Nyquist theorem says that voice samples must be taken how many times per second?
8,000
102
Where are G.711 mu-law and a-law used, respectively? What's the difference between the two?
Mu-law is used in the US and Japan. A-law is used everywhere else.
The codecs are total inversions of each other; wherever mu-law uses 1s, a-law uses 0s.
103
How does RTCP know when to send session data?
It's sent as a percentage of session bandwidth, but at least every 5 seconds.
104
What protocol does Secure RTP use to encrypt RTP data?
AES
105
RTP uses _____ ports and RTCP uses _____ ports.
even; odd
106
Name four items that RTCP tracks
Packet count
Packet delay
Packet loss
Jitter
107
Name a type of network delay that is variable.
Propagation delay
108
How much overhead should be accounted for in calculating the bandwidth of a video stream?
20%
109
End-to-end delay for voice traffic should should be less than...
150 ms
110
Voice packet jitter should be less than...
20 ms
111
Voice packet loss rates should be less than...
1%
112
In a QoS context, applications that are needed for a business to function and require dedicated bandwidth are called...
Mission critical
113
In a QoS context, applications that are interactive with users and require rapid response times are called...
Transactional
114
In a QoS context, applications that are noncritical or uncategorized are called...
Best effort
115
In a QoS context, nonproductive applications that consume excessive amounts of bandwidth are called...
Scavenger
116
What QoS model provides guaranteed bandwidth?
IntServ
117
What is the default QoS model?
Best effort
118
How does Cisco characterize the bandwidth promises in DiffServ?
"Almost guaranteed"
119
Why is IntServ not commonly used?
It isn't scalable
120
Where is admission control performed in IntServ?
On the edge router
121
What is "soft QoS"? Which QoS model is considered soft?
It's QoS where mechanisms are used without prior signaling.
DiffServ is considered soft QoS.
122
True or False: DiffServ is considered an end-to-end QoS strategy.
False
123
WRR and MDRR are examples of what QoS mechanism?
Congestion management
124
RED and WRED are examples of what QoS mechanism?
Congestion avoidance
125
Name two examples of link efficiency mechanisms
Header compression and LFI
126
In a QoS-enabled network, classification is performed on...
...every input interface.
127
Where should marking be performed in a QoS-enabled network?
As closed to the edge as possible, even on the originating device.
128
What QoS mechanism(s) are usually restricted to lower-speed links?
Compression and LFI
129
Name the flow-based queuing algorithm that schedules interactive traffic to the front of a queue and shares the remaining bandwidth among high-bandwidth flows.
WFQ
130
How does WFQ implement tail drop?
It drops the packets of the most aggressive flows.
131
How many queues are available in WFQ for system packets? For RSVP flows?
Eight; 1,000.
132
How many dynamic queues does WFQ use with the default interface bandwidth? What is the configurable range of queues?
256; 16 to 4096 (in powers of 2)
133
This QoS queuing mechanism uses strict priority queuing over multiple configurable queues.
LLQ
134
Name the three QoS mechanisms that are used on router ingress.
Classification, marking, policing.
135
What protocol does AutoQoS use to ensure QoS settings are properly configured?
CDP
136
This router/L3 switch command enables AutoQoS on an interface without trusting any of the incoming markings.
(config-if)# auto qos voip
137
Give the AutoQoS configuration command switches that tell the router/L3 switch to:
1. Believe the incoming QoS markings.
2. Believe incoming QoS markings if there is a IP phone detected on the other end of the wire.
3. Believe incoming QoS markings if there is a Cisco IP SoftPhone detected on the other end of the wire.
1. trust
2. cisco-phone
3. cisco-softphone
