Communications Delta 2
What is the definition of Voice over Internet Protocol (VoIP)?
A technology which allows IP based networks to be utilized for real-time voice applications.
What are the two types of call processing used within a VoIP network?
Centralized Distributed
What are the components of QoS within VoIP networks?
Classification and marking Queuing Congestion Avoidance Policing and Shaping Link Efficiency
What is the definition of Media Gateway Control Protocol?
Client-server call control protocol used by call-control devices such as CUCM to manage and control IP gateways
What are the benefits of VoIP?
Cost Savings Bandwidth Rich applications and features
What is the function of a Publisher Server?
The only server whose database can be altered.
What is the purpose of an Inter-Cluster Trunk?
Facilitates communication between clusters Main trunk extension device inside of a CUCM network
What is the purpose of Survivable Remote Site Technology (SRST)?
Fault tolerance within a CUCM administered VoIP network can be provided through use of this. Capability which can be enabled through a VoIP network to allow calls to be processed and routed between sites in the event that connectivity to the CUCM is lost.
What is Link Efficiency?
Focuses on delivering traffic in the most efficient way?
What is the purpose of Dial Peers?
Software structure that binds a dialed digit string to a voice port or IP address of the destination network. Dial peers are required to be programmed when running CME to facilitate calls beyond your local site.
What is the definition of H.323?
Suite of protocols that provide IP networks with traditional telephony functionality.
What is the definition of QoS?
The ability of the network to provide better or special services to a set of users and applications at the expense of other users and applications.
What is the definition of Class of Control?
The ability to apply calling restrictions to devices.
What is the definition of convergence?
The combination of voice, video, and data services across the same network infrastructure.
What is the definition of transcoding?
The direct digital-to-digital conversion from one codec to another.
What is Class-Based Weighted Fair Queuing (CBWFQ)?
This queuing method allows you to specify guaranteed amounts of traffic for the various classes of traffic. For example, 20% voice, 20% video, 30% other
What is Weighted Fair Queuing?
Tries to balance available bandwidth among all senders. Often the default method applied to serial interfaces.
What is the purpose of the Real Time Monitoring Tool (RMT)?
Allows admins to collect, view, interrupt, and monitor the various counters, trace files, and logs generated by the CUCM.
What is Congestion Avoidance?
Drop enough packets of non-essential traffic
What is the basic Phone-to-Phone call process within a CUCM administered network?
1. Caller dials the distant end and digits are received by CUCM. 2. CUCM performs look up of distant end IP address. 3. CUCM checks the status of the distant end telephone to verify that it is registered adn is able to receive calls. 4. If available, CUCM rings the telephone. 5. Alerted by ringing, distant user takes their phone off-hook. CUCM then connects the telephone sets using RTP, CUCM drops of call.
Identify the VoIP Telephone Initialization Process:
1. VoIP phone connected to switch and receives power over ethernet. 2. Cisco Discovery Protocol ID's which VLAN the phone should be on and delivers the Voice VLAN 3. The VoIP phone requests an IP from the DHCP server 4. VoIP phone contacts TFTP server for configuration file and loads it 5. VoIP phone registers with the CME/CUCM using Skinny Client Control Protocol and is now able to place and receive calls.
What is Classification and Marking?
Allows you to identify and mark real time voice packets so network devices can easily identify them as they traverse the network.
What is the purpose of a Cisco Unified Communications Manager (CUCM)?
Application which runs on a dedicated server providing call processing services for up to 10,000 users.
What is the definition of real-Time Transport Protocol (RTP)?
Based off UDP which was created to provide end-to-end transmission of streaming media. Used to communicate directly between the voice endpoints.
What is the function of a call processor?
Call processing Device Control Directory service Computer telephony integration Trunking Gateway support
What are the four basic components of a VoIP network?
IP network Call processor/controllers Media/signaling gateways Subscriber terminals/Endpoints
What are the characteristics of the Voice VLAN?
Increased performace Improved manageability Physical topology independence Increased security It is common practice to separate voice and data traffic by utilizing VLANs IOT prevent data applications form reaching voice traffic
What is Policy and Shaping?
Limits the amount of bandwidth certain network traffic can use
What is the definition of Cluster?
Multiple servers managed as a single entity, yielding scalability of up to 30,000 users per cluster.
What is the definition of Session Initiation Protocol?
Peer-to-peer protocol in which user agents initiate sessions similar to the method utilized by H.3.2.3 Defines end to end call signaling between devices by using a text based HTTP-like model of communication
Identify the power options associated with Cisco IP phones
Power over Ethernet (POE) switches are required VoIP phones in the Marine Corps are not fielded with external power cords
What is the definition of Call Admission Control?
Prevents IP calls from being extended across the WAN link, if the additional bandwidth required would exceed the CAC allocated bandwidth for concurrent calls thus preventing over subscription.
What is the function of a Subscriber Server?
Primary call controllers responsible for registering phones and setting up calls.
What is the purpose of the Disaster Recovery System (DRS)?
Provides backup and restores capability
What are the four main components of Call Routing in a CUCM network?
Route patterns Route lists Route groups Gateways/trunks
What is the role of the TFTP Server in IP networking?
Serve as a central repository for all required phone configurations in the network.
What is the purpose of Signaling Protocols:
Setup, maintain, and terminate a bi-directional real-time media stream between VoIP subscriber terminals Provide the necessary signaling for VoIP networks to interface with the PTSN.
What is the purpose of Cisco Unified Communications Manager Express (CME)?
VoIP management applications which runs on an integrated services router's IOS Provide call processing in a VoIP network
What is Queuing?
Which packet will be sent first when bandwidth becomes available.
